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Abstract Background Eave spaces are major entry points through which malaria vectors enter houses. Interventions that target mosquitoes at the eaves have recently been developed. However, most of these interventions are based on insecticides for which resistance has been reported. Here we evaluated the efficacy of mosquito electrocuting eave tubes (MEETs) against Anopheles gambiae sensu stricto (An. gambiae s.s.) and Anopheles funestus s.s. under semi-field conditions. Methods Experiments were conducted in two semi-field chambers, each containing one experimental hut. Six electrocuting eave tubes were installed in each hut to assess their impact on laboratory-reared An. gambiae s.s. and An. funestus s.s.. Each species was assessed separately over 10 nights by releasing 200 unfed females per night into each chamber. One volunteer slept in each hut from 7 p.m. to 5 a.m. Mosquitoes were collected indoors and outdoors using mouth and Prokopack aspirators. Results The placement of MEETs significantly reduced the nightly An. gambiae s.s. indoor and outdoor biting, by 21.1% and 37.4%, respectively. Indoor-biting An. funestus s.s. were reduced by 87.5% while outdoor-biting numbers of An. funestus s.s. declined by 10.4%. Conclusions MEETs represent a promising tool for controlling mosquitoes at the point of house entry. Further validation of their potential under natural field conditions is necessary. Several advantages over insecticide-based eave tubes are indicated and discussed in this article. Graphical Abstract

ABSTRACT Daptomycin (DAP) is a cyclic lipopeptide antibiotic that targets the cell membrane and is commonly used for the treatment of multidrug-resistant Staphylococcus aureus infections, especially methicillin-resistant strains (MRSA). Emergence of DAP resistance during DAP therapy is increasingly reported; however, the mechanisms by which resistance occurs are diverse. Using phages in combination with antibiotics is of high interest to circumvent antibiotic resistance, due to their minimal side effects, accessibility, and synergistic effects with antibiotics. Here, we have investigated the relationship between DAP resistance and sensitivity to phage Sb-1 in a cohort of 14 clinical MRSA strains. This cohort consists of four isogenic pairs (a clinical DAP-susceptible parent and its isogenic DAP-resistant variant isolated during DAP treatment), and three DAP-susceptible/DAP-resistant strain pairs are created by traditional serial passaging in the presence of increasing DAP concentrations. Efficiency of plating (EOP) and bacteriophage plaque sizes were recorded, and synergy between the antibacterial agents was tested using the phage-antibiotic combination (PAC) checkerboard method. Plaque sizes and EOP significantly increased (P = 0.019 and P = 0.008, respectively) as strains developed resistance to DAP. The PAC checkerboards conveyed less antagonistic patterns in DAP-resistant mutant strains compared with their DAP-susceptible counterparts. Antagonism was displayed in 71.4% (5/7) of the DAP-susceptible strains, while it was only present in 14.3% (1/7) of the DAP-resistant mutants. Transmission electron microscopy images showed significantly thicker cell walls in DAP-susceptible strains exposed to DAP monotherapy compared with either growth control or DAP-phage (P = 0.0002 and 0.0007, respectively). These data indicate increased sensitivity to phage Sb-1 concurrent with the emergence of DAP resistance.IMPORTANCEMultidrug-resistant Staphylococcus aureus is a threat to the health care system, especially cross-resistance between daptomycin (DAP) and glycopeptides through various mutations such as mprF (which is involved in the modification of membrane phospholipids in some bacteria) and yycG (part of a two-component regulatory system in bacteria that is important for regulating cell wall biosynthesis and other cellular processes) has been reported previously. Our current study shows adjunctive treatment with phage in DAP-resistant strains will lead to synergistic activity and larger phage plaque sizes, translating to elevated lytic performance. The addition of bacteriophage to standard-of-care antibiotic therapies for multidrug-resistant S. aureus infections has the potential to hinder, and possibly revert, resistance to antibiotics. Applying this strategy can potentially lead to the preservation of the current antibiotics. Verification of this salutary outcome in relevant ex vivo and in vivo models of endovascular infections is required to validate translatability.

Objectives: Trivalent inactivated influenza vaccine effectiveness was low in a prospective cohort of healthcare personnel (HCP) in Israel from 2016 to 2019. We conducted a randomised immunogenicity trial of quadrivalent recombinant influenza vaccine (RIV4) and standard-dose inactivated influenza vaccine (IIV4) among frequently and infrequently vaccinated previous cohort participants. Methods: From October 2019 to January 2020, we enrolled and randomly allocated HCP from two Israeli hospitals to receive IIV4 or RIV4. Hemagglutination inhibition (HAI) antibody titres against 2019-2020 vaccine reference influenza viruses were compared between vaccine groups using geometric mean titre (GMT) ratios from sera collected one-month post-vaccination and by frequency of vaccination in the past 5 years (>2 vs ≤2). Results: Among 415 HCP, the GMT ratio comparing RIV4 to IIV4 was 2.0 (95% confidence interval [CI] 1.7-2.7) for A(H1N1)pdm09, 1.6 (95% CI: 1.3-1.9) for A(H3N2), 1.8 (95% CI: 1.4-2.2) for B(Yamagata), and 1.1 (95% CI: 0.9-1.4) for B(Victoria). Similarly, RIV4 elicited higher HAI titres than IIV4 against all 2019-2020 vaccine reference viruses except B(Victoria) among infrequently and frequently vaccinated HCP (lower bound of GMT ratio 95% CIs ≥1.0). Conclusion: RIV4 had improved immunogenicity for influenza vaccine strains among both infrequent and frequent vaccinees compared to standard-dose IIV4. Clinical trials registration: NCT04523324

Gordon M Riha,1 Alyssa Johnson,2 Sadie Arnold,3 Michael S Englehart,1 Simon J Thompson4 1Trauma & General Surgery, Billings Clinic, Billings, MT, USA; 2EMS & Trauma Systems Montana, Chronic Disease Prevention and Health Promotion Bureau, Montana Department of Public Health and Human Services, Helena, MT, USA; 3Laboratory Services, Billings Clinic, Billings, MT, USA; 4Collaborative Science & Innovation, Billings Clinic, Billings, MT, USACorrespondence: Simon J Thompson, Collaborative Science & Innovation, Billings Clinic, Billings, MT, USA, Tel +1 503 267 7314, Fax +1 406 435-1586, Email sthompson11@billingsclinic.orgPurpose: The state of Montana encompasses and defines rural health care as it is known in the United States (US) today. This vast area is punctuated by pockets of health care availability with varying access to blood products for transfusion. Furthermore, timely transport is frequently challenged by weather that may limit air transportation options, resulting in multiple hours in ground transport to definitive care.Patients and Methods: The Montana State Trauma Care Committee (MT-STCC) developed the Montana Interfacility Blood Network (MT-IBN) to ensure blood availability in geographically distanced cases where patients may otherwise not survive. The index case that led to the formal development of the MT-IBN is described, followed by a second case illustrating the IBN process.Results: This process and development manuscript details the innovative efforts of MT-STCC to develop this fledgling idea unique to rural US health care. We review guidelines that have been developed to define broad aspects of the MT-IBN including the reason to share resources, proper packaging, paperwork necessary for transfer, and how to provide resources directly to the patient. Finally, we describe implementation within the state.Conclusion: The MT-IBN was developed by MT-STCC to facilitate the hand-off of lifesaving blood to patients being transported by ground to definitive care in Montana without having to stop at an intermediary facility. This has already led to lives saved in areas that are limited in blood availability due to rurality.Keywords: rural health care, blood transfusion, health services accessibility, trauma

Abstract Background Symptoms of COVID-19 including fatigue and dyspnea, may persist for weeks to months after SARS-CoV-2 infection. This study compared self-reported disability among SARS-CoV-2-positive and negative persons with mild to moderate COVID-19-like illness who presented for outpatient care before widespread COVID-19 vaccination. Methods Unvaccinated adults with COVID-19-like illness enrolled within 10 days of illness onset at three US Flu Vaccine Effectiveness Network sites were tested for SARS-CoV-2 by molecular assay. Enrollees completed an enrollment questionnaire and two follow-up surveys (7–24 days and 2–7 months after illness onset) online or by phone to assess illness characteristics and health status. The second follow-up survey included questions measuring global health, physical function, fatigue, and dyspnea. Scores in the four domains were compared by participants’ SARS-CoV-2 test results in univariate analysis and multivariable Gamma regression. Results During September 22, 2020 – February 13, 2021, 2712 eligible adults were enrolled, 1541 completed the first follow-up survey, and 650 completed the second follow-up survey. SARS-CoV-2-positive participants were more likely to report fever at acute illness but were otherwise comparable to SARS-CoV-2-negative participants. At first follow-up, SARS-CoV-2-positive participants were less likely to have reported fully or mostly recovered from their illness compared to SARS-CoV-2-negative participants. At second follow-up, no differences by SARS-CoV-2 test results were detected in the four domains in the multivariable model. Conclusion Self-reported disability was similar among outpatient SARS-CoV-2-positive and -negative adults 2–7 months after illness onset.

IntroductionStaphylococcus aureus bacteremia (SAB) is a life-threatening infection particularly involving methicillin-resistant S. aureus (MRSA). In contrast to resolving MRSA bacteremia (RB), persistent MRSA bacteremia (PB) blood cultures remain positive despite appropriate antibiotic treatment. Host immune responses distinguishing PB vs. RB outcomes are poorly understood. Here, integrated transcriptomic, IL-10 cytokine levels, and genomic analyses sought to identify signatures differentiating PB vs. RB outcomes.MethodsWhole-blood transcriptomes of propensity-matched PB (n=28) versus RB (n=30) patients treated with vancomycin were compared in one independent training patient cohort. Gene expression (GE) modules were analyzed and prioritized relative to host IL-10 cytokine levels and DNA methyltransferase-3A (DNMT3A) genotype.ResultsDifferential expression of T and B lymphocyte gene expression early in MRSA bacteremia discriminated RB from PB outcomes. Significant increases in effector T and B cell signaling pathways correlated with RB, lower IL-10 cytokine levels and DNMT3A heterozygous A/C genotype. Importantly, a second PB and RB patient cohort analyzed in a masked manner demonstrated high predictive accuracy of differential signatures.DiscussionCollectively, the present findings indicate that human PB involves dysregulated immunity characterized by impaired T and B cell responses associated with excessive IL-10 expression in context of the DNMT3A A/A genotype. These findings reveal distinct immunologic programs in PB vs. RB outcomes, enable future studies to define mechanisms by which host and/or pathogen drive differential signatures and may accelerate prediction of PB outcomes. Such prognostic assessment of host risk could significantly enhance early anti-infective interventions to avert PB and improve patient outcomes.

Both SARS-CoV-2 and influenza virus can be transmitted by asymptomatic, presymptomatic, or symptomatic infected persons. We assessed effects on work attendance while ill before and during the COVID-19 pandemic in the United States by analyzing data collected prospectively from persons with acute respiratory illnesses enrolled in a multistate study during 2018–2022. Persons with previous hybrid work experience were significantly less likely to work onsite on the day before through the first 3 days of illness than those without that experience, an effect more pronounced during the COVID-19 pandemic than during prepandemic influenza seasons. Persons with influenza or COVID-19 were significantly less likely to work onsite than persons with other acute respiratory illnesses. Among persons with positive COVID-19 test results available by the second or third day of illness, few worked onsite. Hybrid and remote work policies might reduce workplace exposures and help reduce spread of respiratory viruses.

Abstract Background Hemophilia A (HEMA) is an X-linked bleeding disorder caused by reduced/absent coagulation factor VIII expression, as a result of pathogenic variants in the F8 gene. Preimplantation prevention of HEMA should ideally include direct pathogenic F8 variant detection, complemented by linkage analysis of flanking markers to identify the high-risk F8 allele. Linkage analysis is particularly indispensable when the pathogenic variant cannot be detected directly or identified. This study evaluated the suitability of a panel of F8 intragenic and extragenic short tandem repeat markers for standalone linkage-based preimplantation genetic testing for monogenic disorder (PGT-M) of the Inv22 pathogenic variant, an almost 600 kb paracentric inversion responsible for almost half of all severe HEMA globally, for which direct detection is challenging. Methods Thirteen markers spanning 1 Mb and encompassing both F8 and the Inv22 inversion interval were genotyped in 153 unrelated females of Viet Kinh ethnicity. Results All individuals were heterozygous for ≥ 1 marker, ~ 90% were heterozygous for ≥ 1 of the five F8 intragenic markers, and almost 98% were heterozygous for ≥ 1 upstream (telomeric) and ≥ 1 downstream (centromeric) markers. A prospective PGT-M couple at risk of transmitting F8 Inv22 were fully informative at four marker loci (2 intra-inversion, 1 centromeric, 1 telomeric) and partially informative at another five (2 intra-inversion, 3 centromeric), allowing robust phasing of low- and high-risk haplotypes. In vitro fertilization produced three embryos, all of which clearly inherited the low-risk maternal allele, enabling reliable unaffected diagnoses. A single embryo transfer produced a clinical pregnancy, which was confirmed as unaffected by amniocentesis and long-range PCR, and a healthy baby girl was delivered at term. Conclusion Robust and reliable PGT-M of HEMA, including the common F8 Inv22 pathogenic variant, can be achieved with sufficient informative intragenic and flanking markers.

Abstract Background Early-evening and outdoor-biting mosquitoes may compromise the effectiveness of frontline malaria interventions, notably insecticide-treated nets (ITNs). This study aimed to evaluate the efficacy of low-cost insecticide-treated eave ribbons and sandals as supplementary interventions against indoor-biting and outdoor-biting mosquitoes in south-eastern Tanzania, where ITNs are already widely used. Methods This study was conducted in three villages, with 72 households participating (24 households per village). The households were divided into four study arms and assigned: transfluthrin-treated sandals (TS), transfluthrin-treated eave ribbons (TER), a combination of TER and TS, or experimental controls. Each arm had 18 households, and all households received new ITNs. Mosquitoes were collected using double net traps (to assess outdoor biting), CDC light traps (to assess indoor biting), and Prokopack aspirators (to assess indoor resting). Protection provided by the interventions was evaluated by comparing mosquito densities between the treatment and control arms. Additional tests were done in experimental huts to assess the mortality of wild mosquitoes exposed to the treatments or controls. Results TERs reduced indoor-biting, indoor-resting and outdoor-biting Anopheles arabiensis by 60%, 73% and 41%, respectively, while TS reduced the densities by 18%, 40% and 42%, respectively. When used together, TER & TS reduced indoor-biting, indoor-resting and outdoor-biting An. arabiensis by 53%, 67% and 57%, respectively. Protection against Anopheles funestus ranged from 42 to 69% with TER and from 57 to 74% with TER & TS combined. Mortality of field-collected mosquitoes exposed to TER, TS or both interventions was 56–78% for An. arabiensis and 47–74% for An. funestus. Conclusion Transfluthrin-treated eave ribbons and sandals or their combination can offer significant household-level protection against malaria vectors. Their efficacy is magnified by the transfluthrin-induced mortality, which was observed despite the prevailing pyrethroid resistance in the study area. These results suggest that TER and TS could be useful supplementary tools against residual malaria transmission in areas where ITN coverage is high but additional protection is needed against early-evening and outdoor-biting mosquitoes. Further research is needed to validate the performance of these tools in different settings, and assess their long-term effectiveness and feasibility for malaria control.

Persons with COVID-19–like illnesses are advised to stay home to reduce the spread of SARS-CoV-2. We assessed relationships between telework experience and COVID-19 illness with work attendance when ill. Adults experiencing fever, cough, or loss of taste or smell who sought healthcare or COVID-19 testing in the United States during March–November 2020 were enrolled. Adults with telework experience before illness were more likely to work at all (onsite or remotely) during illness (87.8%) than those with no telework experience (49.9%) (adjusted odds ratio 5.48, 95% CI 3.40–8.83). COVID-19 case-patients were less likely to work onsite (22.1%) than were persons with other acute respiratory illnesses (37.3%) (adjusted odds ratio 0.36, 95% CI 0.24–0.53). Among COVID-19 case-patients with telework experience, only 6.5% worked onsite during illness. Telework experience before illness gave mildly ill workers the option to work and improved compliance with public health recommendations to stay home during illness.

Here, by sequencing viruses from individuals in multiple households, Bendall et al. find that SARS-CoV-2 transmission bottleneck does not vary between individuals infected with pre-variant lineages and those infected with highly transmissible Alpha, Delta, or Omicron variants, suggesting these tight bottlenecks will limit the spread of new mutations.

Abstract Lymphangioleiomyomatosis (LAM) is a rare disease involving cystic lung destruction by invasive LAM cells. These cells harbor loss‐of‐function mutations in TSC2, conferring hyperactive mTORC1 signaling. Here, tissue engineering tools are employed to model LAM and identify new therapeutic candidates. Biomimetic hydrogel culture of LAM cells is found to recapitulate the molecular and phenotypic characteristics of human disease more faithfully than culture on plastic. A 3D drug screen is conducted, identifying histone deacetylase (HDAC) inhibitors as anti‐invasive agents that are also selectively cytotoxic toward TSC2−/− cells. The anti‐invasive effects of HDAC inhibitors are independent of genotype, while selective cell death is mTORC1‐dependent and mediated by apoptosis. Genotype‐selective cytotoxicity is seen exclusively in hydrogel culture due to potentiated differential mTORC1 signaling, a feature that is abrogated in cell culture on plastic. Importantly, HDAC inhibitors block invasion and selectively eradicate LAM cells in vivo in zebrafish xenografts. These findings demonstrate that tissue‐engineered disease modeling exposes a physiologically relevant therapeutic vulnerability that would be otherwise missed by conventional culture on plastic. This work substantiates HDAC inhibitors as possible therapeutic candidates for the treatment of patients with LAM and requires further study.

ABSTRACT Persistent methicillin-resistant Staphylococcus aureus (MRSA) endovascular infections represent a serious public health threat. We recently demonstrated that the presence of a novel prophage ϕSA169 was associated with vancomycin (VAN) treatment failure in experimental MRSA endocarditis. In this study, we assessed the role of a ϕSA169 gene, ϕ80α_gp05 (gp05), in VAN-persistent outcome using gp05 isogenic MRSA strain sets. Of note, Gp05 significantly influences the intersection of MRSA virulence factors, host immune responses, and antibiotic treatment efficacy, including the following: (i) activity of the significant energy-yielding metabolic pathway (e.g., tricarboxylic acid cycle); (ii) carotenoid pigment production; (iii) (p)ppGpp (guanosine tetra- and pentaphosphate) production, which activates the stringent response and subsequent downstream functional factors (e.g., phenol-soluble modulins and polymorphonuclear neutrophil bactericidal activity); and (iv) persistence to VAN treatment in an experimental infective endocarditis model. These data suggest that Gp05 is a significant virulence factor which contributes to the persistent outcomes in MRSA endovascular infection by multiple pathways. IMPORTANCE Persistent endovascular infections are often caused by MRSA strains that are susceptible to anti-MRSA antibiotics in vitro by CLSI breakpoints. Thus, the persistent outcome represents a unique variant of traditional antibiotic resistance mechanisms and a significant therapeutic challenge. Prophage, a critical mobile genetic element carried by most MRSA isolates, provides their bacterial host with metabolic advantages and resistance mechanisms. However, how prophage-encoded virulence factors interact with the host defense system and antibiotics, driving the persistent outcome, is not well known. In the current study, we demonstrated that a novel prophage gene, gp05, significantly impacts tricarboxylic acid cycle activity, stringent response, and pigmentation, as well as vancomycin treatment outcome in an experimental endocarditis model using isogenic gp05 overexpression and chromosomal deletion mutant MRSA strain sets. The findings significantly advance our understanding of the role of Gp05 in persistent MRSA endovascular infection and provide a potential target for development of novel drugs against these life-threatening infections.

ABSTRACT Methicillin-resistant Staphylococcus aureus (MRSA) infections are an increasing concern due to their intrinsic resistance to most standard-of-care β-lactam antibiotics. Recent studies of clinical isolates have documented a novel phenotype, termed NaHCO3 responsiveness, in which a substantial proportion of MRSA strains exhibit enhanced susceptibility to β-lactams such as cefazolin and oxacillin in the presence of NaHCO3. A bicarbonate transporter, MpsAB (membrane potential-generating system), was recently found in S. aureus, where it plays a role in concentrating NaHCO3 for anaplerotic pathways. Here, we investigated the role of MpsAB in mediating the NaHCO3 responsiveness phenotype. Radiolabeled NaH14CO3 uptake profiling revealed significantly higher accumulation in NaHCO3-responsive vs nonresponsive MRSA strains when grown in ambient air. In contrast, under 5% CO2 conditions, NaHCO3-responsive (but not nonresponsive) strains exhibited repressed uptake. Oxacillin MICs were measured in four prototype strains and their mpsABC deletion mutants in the presence of NaHCO3 supplementation under 5% CO2 conditions. NaHCO3-mediated reductions in oxacillin MICs were observed in the responsive parental strains but not in mpsABC deletion mutants. No significant impact on oxacillin MICs was observed in the nonresponsive strains under the same conditions. Transcriptional and translational studies were carried out using both quantitative reverse transcription-PCR (qRT-PCR) and mpsA-green fluorescent protein (GFP) fusion constructs; these investigations showed that mpsA expression and translation were significantly upregulated during mid-exponential-phase growth in oxacillin-NaHCO3-supplemented medium in responsive versus nonresponsive strains. Taken together, these data show that the NaHCO3 transporter MpsABC is a key contributor to the NaHCO3–β-lactam responsiveness phenotype in MRSA. IMPORTANCE MRSA infections are increasingly difficult to treat, due in part to their resistance to most β-lactam antibiotics. A novel and relatively common phenotype, termed NaHCO3 responsiveness, has been identified in which MRSA strains show increased susceptibility in vitro and in vivo to β-lactams in the presence of NaHCO3. A recently described S. aureus NaHCO3 transporter, MpsAB, is involved in intracellular NaHCO3 concentration for anaplerotic pathways. We investigated the role of MpsAB in mediating the NaHCO3 responsiveness phenotype in four prototype MRSA strains (two responsive and two nonresponsive). We demonstrated that MpsABC is an important contributor to the NaHCO3–β-lactam responsiveness phenotype. Our study adds to the growing body of well-defined characteristics of this novel phenotype, which could potentially translate to alternative targets for MRSA treatment using β-lactams.

Abstract Background In sub-Saharan Africa, house design and ventilation affects the number of malaria mosquito vectors entering houses. This study hypothesized that indoor light from a CDC-light trap, visible from outside a hut, would increase entry of Anopheles arabiensis, an important malaria vector, and examined whether ventilation modifies this effect. Methods Four inhabited experimental huts, each situated within a large chamber, were used to assess how light and ventilation affect the number of hut-entering mosquitoes in Tanzania. Each night, 300 female laboratory-reared An. arabiensis were released inside each chamber for 72 nights. Nightly mosquito collections were made using light traps placed indoors. Temperature and carbon dioxide concentrations were measured using data loggers. Treatments and sleepers were rotated between huts using a randomized block design. Results When indoor light was visible outside the huts, there was an 84% increase in the odds of collecting mosquitoes indoors (Odds ratio, OR = 1.84, 95% confidence intervals, 95% CI 1.74–1.95, p

Abstract Background The measurement of circulating substrate concentrations does not provide information about substrate kinetics. It, therefore, remains unclear if a decrease in plasma concentration of albumin, as seen during critical illness, is a consequence of suppressed production in the liver or increased peripheral clearance. In this study, using stable isotope tracer infusions, we measured albumin and fibrinogen kinetics in septic patients and in a control group of non-septic subjects. Methods With the approval from the institutional Research Ethics Board and after obtaining written informed consent from patients or their substitute decision maker, mechanically ventilated patients with sepsis and patients scheduled for elective coronary artery bypass grafting were enrolled. Patients in the non-sepsis group were studied on the day before surgery. The stable isotope L-[ring-2H5]phenylalanine was used to measure absolute synthesis rates (ASR) of albumin and fibrinogen. A priming dose of L-[ring-2H5]phenylalanine (4 µmol/kg) was given followed by a six-hour infusion at a rate of 0.15 µmol/kg/min. At baseline and hourly thereafter, blood was drawn to measure isotope enrichments by gas chromatography/mass spectrometry. Very low density lipoprotein apolipoprotein-B 100 isotopic enrichment was used to represent the isotopic enrichment of the phenylalanine precursor pool from which the liver synthesizes proteins. Plasma albumin and fibrinogen concentrations were also measured. Results Mean plasma albumin in septic patients was decreased when compared to non-septic patients, while synthesis rates were comparable. Mean plasma fibrinogen and ASR in septic patients was increased when compared to non-septic patients. In non-septic patients, no statistically significant correlation between plasma albumin and ASR was observed but plasma fibrinogen significantly correlated with ASR. In septic patients, plasma albumin and fibrinogen significantly correlated with ASR. Conclusions While septic patients showed lower plasma albumin levels than non-septic patients, albumin synthesis was similar in the two groups suggesting that hypoalbuminemia during sepsis was not caused by suppressed hepatic production but a result of enhanced clearance from the circulation. Hyperfibrinogenemia in septic patients was a consequence of increased fibrinogen production. Trial registration: ClinicalTrials.gov: NCT02865408 (registered on August 12, 2016) and ClinicalTrials.gov: NCT02549443 (registered on September 15, 2015).

Abstract Immune checkpoint inhibitor (ICI)‐associated myocarditis is a rare, potentially life‐threatening complication of immunotherapy. We report a case of a 60‐year‐old female with a history of colorectal cancer treated with nivolumab immunotherapy who presented with new cardiomyopathy complicated by cardiogenic shock and ventricular arrhythmias. Treatment of ICI‐associated myocarditis requires aggressive immunosuppression and supportive therapy. In this case, the patient required advanced mechanical circulatory support as a bridge to recovery. This case highlights the complexity of diagnosis, haemodynamic management, and treatment of fulminant ICI myocarditis.

Abstract Supplementary tools are required to address the limitations of insecticide-treated nets (ITNs) and indoor residual spraying (IRS), which are currently the core vector control methods against malaria in Africa. The eave ribbons technology exploits the natural house-entry behaviours of major malaria vectors to deliver mosquitocidal or repellent actives around eave spaces through which the Anopheles mosquitoes usually enter human dwellings. They confer protection by preventing biting indoors and in the peri-domestic outdoor spaces, and also killing a significant proportion of the mosquitoes. Current versions of eave ribbons are made of low-cost hessian fabric infused with candidate insecticides and can be easily fitted onto multiple house types without any additional modifications. This article reviews the evidence for efficacy of the technology, and discusses its potential as affordable and versatile supplementary approach for targeted and efficient control of mosquito-borne diseases, particularly malaria. Given their simplicity and demonstrated potential in previous studies, future research should investigate ways to optimize scalability and effectiveness of the ribbons. It is also important to assess whether the ribbons may constitute a less-cumbersome, but more affordable substitute for other interventions, such as IRS, by judiciously using lower quantities of selected insecticides targeted around eave spaces to deliver equivalent or greater suppression of malaria transmission.

ABSTRACT Methicillin-resistant Staphylococcus aureus (MRSA) strains pose major treatment challenges due to their innate resistance to most β-lactams under standard in vitro antimicrobial susceptibility testing conditions. A novel phenotype among MRSA, termed “NaHCO3 responsiveness,” where certain strains display increased susceptibility to β-lactams in the presence of NaHCO3, has been identified among a relatively large proportion of MRSA isolates. One underlying mechanism of NaHCO3 responsiveness appears to be related to decreased expression and altered functionality of several genes and proteins involved in cell wall synthesis and maturation. Here, we studied the impact of NaHCO3 on wall teichoic acid (WTA) synthesis, a process intimately linked to peptidoglycan (PG) synthesis and functionality, in NaHCO3-responsive versus -nonresponsive MRSA isolates. NaHCO3 sensitized responsive MRSA strains to cefuroxime, a specific penicillin-binding protein 2 (PBP2)-inhibitory β-lactam known to synergize with early WTA synthesis inhibitors (e.g., ticlopidine). Combining cefuroxime with ticlopidine with or without NaHCO3 suggested that these latter two agents target the same step in WTA synthesis. Further, NaHCO3 decreased the abundance and molecular weight of WTA only in responsive strains. Additionally, NaHCO3 stimulated increased autolysis and aberrant cell division in responsive strains, two phenotypes associated with disruption of WTA synthesis. Of note, studies of key genes involved in the WTA biosynthetic pathway (e.g., tarO, tarG, dltA, and fmtA) indicated that the inhibitory impact of NaHCO3 on WTA biosynthesis in responsive strains likely occurred posttranslationally. IMPORTANCE MRSA is generally viewed as resistant to standard β-lactam antibiotics. However, a NaHCO3-responsive phenotype is observed in a substantial proportion of clinical MRSA strains in vitro, i.e., isolates which demonstrate enhanced susceptibility to standard β-lactam antibiotics (e.g., oxacillin) in the presence of NaHCO3. This phenotype correlates with increased MRSA clearance in vivo by standard β-lactam antibiotics, suggesting that patients with infections caused by such MRSA strains might be amenable to treatment with β-lactams. The mechanism(s) behind this phenotype is not fully understood but appears to involve mecA-PBP2a production and maturation axes. Our study adds significantly to this body of knowledge in terms of additional mechanistic targets of NaHCO3 in selected MRSA strains. This investigation demonstrates that NaHCO3 has direct impacts on S. aureus wall teichoic acid biosynthesis in NaHCO3-responsive MRSA. These findings provide an additional target for new agents being designed to synergistically kill MRSA using β-lactam antibiotics.

Invasive methicillin-resistant Staphylococcus aureus (MRSA) infections are leading causes of morbidity and mortality that are complicated by increasing resistance to conventional antibiotics. Thus, minimizing virulence and enhancing antibiotic efficacy against MRSA is a public health imperative. We originally demonstrated that diflunisal (DIF; [2-hydroxy-5-(2,4-difluorophenyl) benzoic acid]) inhibits S. aureus virulence factor expression. To investigate pharmacophores that are active in this function, we evaluated a library of structural analogues for their efficacy to modulate virulence phenotypes in a panel of clinically relevant S. aureus isolates in vitro. Overall, the positions of the phenyl, hydroxyl, and carboxylic moieties and the presence or type of halogen (F vs. Cl) influenced the efficacy of compounds in suppressing hemolysis, proteolysis, and biofilm virulence phenotypes. Analogues lacking halogens inhibited proteolysis to an extent similar to DIF but were ineffective at reducing hemolysis or biofilm production. In contrast, most analogues lacking the hydroxyl or carboxylic acid groups did not suppress proteolysis but did mitigate hemolysis and biofilm production to an extent similar to DIF. Interestingly, chirality and the substitution of fluorine with chlorine resulted in a differential reduction in virulence phenotypes. Together, this pattern of data suggests virulence-suppressing pharmacophores of DIF and structural analogues integrate halogen, hydroxyl, and carboxylic acid moiety stereochemistry. The anti-virulence effects of DIF were achieved using concentrations that are safe in humans, do not impair platelet antimicrobial functions, do not affect S. aureus growth, and do not alter the efficacy of conventional antibiotics. These results offer proof of concept for using novel anti-virulence strategies as adjuvants to antibiotic therapy to address the challenge of MRSA infection.

Abstract Augmentation genioplasty is a common surgical procedure with extremely low infection rates. We present the case of a healthy middle‐aged woman who experienced years of chronic infection after chin implantation due to an exposed mandibular canine root, which is exceedingly rare. Awareness of this potential complication may reduce patient morbidity.

The Streptococcus mitis-oralis subgroup of viridans group streptococci are important human pathogens. We previously showed that a substantial portion of S. mitis-oralis strains (>25%) are ‘destined’ to develop rapid, high-level, and stable daptomycin (DAP) resistance (DAP-R) during DAP exposures in vitro. Such DAP-R is often accompanied by perturbations in distinct membrane phenotypes and metabolic pathways. The current study evaluated two S. oralis bloodstream isolates, 73 and 205. Strain 73 developed stable, high-level DAP-R (minimum inhibitory concentration [MIC] > 256 µg/mL) within 2 days of in vitro DAP passage (“high level” DAP-R [HLDR]). In contrast, strain 205 evolved low-level and unstable DAP-R (MIC = 8 µg/mL) under the same exposure conditions in vitro (“non-HLDR”). Comparing the parental 73 vs. 73-D2 (HLDR) strain-pair, we observed the 73-D2 had the following major differences: (i) altered cell membrane (CM) phospholipid profiles, featuring the disappearance of phosphatidylglycerol (PG) and cardiolipin (CL), with accumulation of the PG-CL pathway precursor, phosphatidic acid (PA); (ii) enhanced CM fluidity; (iii) increased DAP surface binding; (iv) reduced growth rates; (v) decreased glucose utilization and lactate accumulation; and (vi) increased enzymatic activity within the glycolytic (i.e., lactate dehydrogenase [LDH]) and lipid biosynthetic (glycerol-3-phosphate dehydrogenase [GPDH]) pathways. In contrast, the 205 (non-HLDR) strain-pair did not show these same phenotypic or metabolic changes over the 2-day DAP exposure. WGS analyses confirmed the presence of mutations in genes involved in the above glycolytic and phospholipid biosynthetic pathways in the 73-D2 passage variant. These data suggest that S. oralis strains which are ‘destined’ to rapidly develop HLDR do so via a conserved cadre of genotypic, membrane phenotypic, and metabolic adaptations.

Virulence factor expression is integral to pathogenicity of Staphylococcus aureus. We previously demonstrated that aspirin, through its major metabolite, salicylic acid (SAL), modulates S. aureus virulence phenotypes in vitro and in vivo. We compared salicylate metabolites and a structural analogue for their ability to modulate S. aureus virulence factor expression and phenotypes: (i) acetylsalicylic acid (ASA, aspirin); (ii) ASA metabolites, salicylic acid (SAL), gentisic acid (GTA) and salicyluric acid (SUA); or (iii) diflunisal (DIF), a SAL structural analogue. None of these compounds altered the growth rate of any strain tested. ASA and its metabolites SAL, GTA and SUA moderately impaired hemolysis and proteolysis phenotypes in multiple S. aureus strain backgrounds and their respective deletion mutants. Only DIF significantly inhibited these virulence phenotypes in all strains. The kinetic profiles of ASA, SAL or DIF on expression of hla (alpha hemolysin), sspA (V8 protease) and their regulators (sigB, sarA, agr (RNAIII)) were assessed in two prototypic strain backgrounds: SH1000 (methicillin-sensitive S. aureus; MSSA) and LAC-USA300 (methicillin-resistant S. aureus; MRSA). DIF induced sigB expression which is coincident with the significant inhibition of RNAIII expression in both strains and precedes significant reductions in hla and sspA expression. The inhibited expression of these genes within 2 h resulted in the durable suppression of hemolysis and proteolysis phenotypes. These results indicate that DIF modulates the expression of key virulence factors in S. aureus via a coordinated impact on their relevant regulons and target effector genes. This strategy may hold opportunities to develop novel antivirulence strategies to address the ongoing challenge of antibiotic-resistant S. aureus.

The results of the creation of a high-temperature spin injector based on EuO: Fe composite material are discussed. Their magnetic, electrical, structural and resonance parameters are given in a wide range of temperatures and an external magnetic field. A model calculation of the electronic spectrum of the solid solution Eu–Fe–O, responsible for the manifestation of the outstanding properties of the composite, is performed. The possibility of creating semiconductor spin electronics devices capable of operating at room temperature is shown.

Influenza exposure in early childhood can affect the immune response to distinct viral strains later in life. Here, Gouma et al. show that contemporary 3c2.A H3N2 virus infections boost non-neutralizing H3N2 antibodies in middle-aged individuals, potentially leaving them vulnerable to recurrent infections.

Abstract The goal of nutrition support is to provide the substrates required to match the bioenergetic needs of the patient and promote the net synthesis of macromolecules required for the preservation of lean mass, organ function, and immunity. Contemporary observational studies have exposed the pervasive undernutrition of critically ill patients and its association with adverse clinical outcomes. The intuitive hypothesis is that optimization of nutrition delivery should improve ICU clinical outcomes. It is therefore surprising that multiple large randomized controlled trials have failed to demonstrate the clinical benefit of restoring or maximizing nutrient intake. This may be in part due to the absence of biological markers that identify patients who are most likely to benefit from nutrition interventions and that monitor the effects of nutrition support. Here, we discuss the need for practical risk stratification tools in critical care nutrition, a proposed rationale for targeted biomarker development, and potential approaches that can be adopted for biomarker identification and validation in the field.

Abstract Background Viridans group streptococci of the Streptococcus mitis-oralis subgroup are important endovascular pathogens. They can rapidly develop high-level and durable non-susceptibility to daptomycin both in vitro and in vivo upon exposure to daptomycin. Two consistent genetic adaptations associated with this phenotype (i.e., mutations in cdsA and pgsA) lead to the depletion of the phospholipids, phosphatidylglycerol and cardiolipin, from the bacterial membrane. Such alterations in phospholipid biosynthesis will modify carbon flow and change the bacterial metabolic status. To determine the metabolic differences between daptomycin-susceptible and non-susceptible bacteria, the physiology and metabolomes of S. mitis-oralis strains 351 (daptomycin-susceptible) and 351-D10 (daptomycin non-susceptible) were analyzed. S. mitis-oralis strain 351-D10 was made daptomycin non-susceptible through serial passage in the presence of daptomycin. Results Daptomycin non-susceptible S. mitis-oralis had significant alterations in glucose catabolism and a re-balancing of the redox status through amino acid biosynthesis relative to daptomycin susceptible S. mitis-oralis. These changes were accompanied by a reduced capacity to generate biomass, creating a fitness cost in exchange for daptomycin non-susceptibility. Conclusions S. mitis-oralis metabolism is altered in daptomycin non-susceptible bacteria relative to the daptomycin susceptible parent strain. As demonstrated in Staphylococcus aureus, inhibiting the metabolic changes that facilitate the transition from a daptomycin susceptible state to a non-susceptible one, inhibits daptomycin non-susceptibility. By preventing these metabolic adaptations in S. mitis-oralis, it should be possible to deter the formation of daptomycin non-susceptibility.

Abstract: Disease relapse remains the leading cause of failure after autologous stem cell transplantation (ASCT) for patients with relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL). We conducted a phase 2, multicenter, single-arm study of the anti–PD-1 monoclonal antibody pembrolizumab given after ASCT in patients with chemosensitive DLBCL, hypothesizing that it would improve the progression-free survival (PFS) at 18 months after ASCT (primary endpoint) from 60% to 80%. Pembrolizumab was administered at 200 mg IV every 3 weeks for up to 8 cycles, starting within 21 days of post-ASCT discharge. Twenty-nine patients were treated on this study; 62% completed all 8 cycles. Seventy-nine percent of patients experienced at least one grade 3 or higher adverse event, and 34% experienced at least one grade 2 or higher immune-related adverse event. Overall, 59% of patients were alive and progression free at 18 months, which did not meet the primary endpoint. The 18-month overall survival was 93%. In conclusion, pembrolizumab was successfully administered as post-ASCT consolidation in patients with R/R DLBCL, but the PFS did not meet the protocol-specific primary objective and therefore does not support a larger confirmatory study. This trial was registered at www.clinicaltrials.gov as #NCT02362997.

Background Understanding mosquito biting behaviours is important for designing and evaluating protection methods against nuisance biting and mosquito-borne diseases (e.g. dengue, malaria and zika). We investigated the preferred biting sites by Aedes aegypti and Anopheles arabiensis on adult volunteers in standing or sleeping positions; and estimated the theoretical protection limits affordable from protective clothing or repellent-treated footwear. Methods Adult volunteers dressed in shorts and t-shirts were exposed to infection-free laboratory-reared mosquitoes inside screened chambers from 6am to noon (for day-biting Ae. aegypti) or 6pm to midnight (night-biting An. arabiensis). Attempted bites on different body parts were recorded. Comparative observations were made on same volunteers while wearing sandals treated with transfluthrin, a vapour-phase pyrethroid that kills and repels mosquitoes. Results An. arabiensis bites were mainly on the lower limbs of standing volunteers (95.9% of bites below the knees) but evenly-distributed over all exposed body surfaces when the volunteers were on sleeping positions (only 28.8% bites below knees). Ae. aegypti bites were slightly concentrated on lower limbs of standing volunteers (47.7% below knees), but evenly-distributed on sleeping volunteers (23.3% below knees). Wearing protective clothing that leave only hands and head uncovered (e.g. socks + trousers + long-sleeved shirts) could theoretically prevent 78–83% of bites during sleeping, and at least 90% of bites during non-sleeping hours. If the feet are also exposed, protection declines to as low as 36.3% against Anopheles. The experiments showed that transfluthrin-treated sandals reduced An. arabiensis by 54–86% and Ae. aegypti by 32–39%, but did not change overall distributions of bites. Conclusion Biting by An. arabiensis and Ae. aegypti occur mainly on the lower limbs, though this proclivity is less pronounced in the Aedes species. However, when hosts are on sleeping positions, biting by both species is more evenly-distributed over the exposed body surfaces. High personal protection might be achieved by simply wearing long-sleeved clothing, though protection against Anopheles particularly requires covering of feet and lower legs. The transfluthrin-treated footwear can reduce biting risk, especially by An. arabiensis. These findings could inform the design and use of personal protection tools (both insecticidal and non-insecticidal) against mosquitoes and mosquito-borne diseases.

Summary: Sterilising immunity that blocks infection for life, and thus prevents illness after infection, is the ultimate goal for vaccines. Neither influenza infection nor vaccination provide sterilising immunity. Mutations during influenza viral genome replication result in the emergence of viruses that evade immunity and cause reinfections. Waning of immunity also results in reinfections to homologous influenza viruses. However, immunity might limit the severity of disease after infection or vaccination (ie, immunoattenuation). We provide a comprehensive examination of experimental and observational peer reviewed evidence since 1933, when the first influenza virus was isolated, on whether immunity blocks subsequent infection or attenuates illness. Although an abundance of experimental evidence supports immunoattenuation, clinical evidence is rudimentary and conflicting. To the extent that immunoattenuation occurs, understanding the varied pathways to illness, pathogenesis, clinical manifestations, and correlates of attenuation can improve the design and evaluation of influenza vaccines. By elucidating the mechanisms of immunoattenuation and phenotypes of illness, we clarify ambiguities and identify unmet needs that, if addressed with priority, could strategically improve the design of vaccines for the prevention of influenza.

ABSTRACT Persistent methicillin-resistant Staphylococcus aureus (MRSA) endovascular infections represent a significant clinically challenging subset of invasive, life-threatening S. aureus infections. We have recently demonstrated that purine biosynthesis plays an important role in such persistent infections. Cyclic di-AMP (c-di-AMP) is an essential and ubiquitous second messenger that regulates many cellular pathways in bacteria. However, whether there is a regulatory connection between the purine biosynthesis pathway and c-di-AMP impacting persistent outcomes was not known. Here, we demonstrated that the purine biosynthesis mutant MRSA strain, the ΔpurF strain (compared to its isogenic parental strain), exhibited the following significant differences in vitro: (i) lower ADP, ATP, and c-di-AMP levels; (ii) less biofilm formation with decreased extracellular DNA (eDNA) levels and Triton X-100-induced autolysis paralleling enhanced expressions of the biofilm formation-related two-component regulatory system lytSR and its downstream gene lrgB; (iii) increased vancomycin (VAN)-binding and VAN-induced lysis; and (iv) decreased wall teichoic acid (WTA) levels and expression of the WTA biosynthesis-related gene, tarH. Substantiating these data, the dacA (encoding diadenylate cyclase enzyme required for c-di-AMP synthesis) mutant strain (dacAG206S strain versus its isogenic wild-type MRSA and dacA-complemented strains) showed significantly decreased c-di-AMP levels, similar in vitro effects as seen above for the purF mutant and hypersusceptible to VAN treatment in an experimental biofilm-related MRSA endovascular infection model. These results reveal an important intersection between purine biosynthesis and c-di-AMP that contributes to biofilm-associated persistence in MRSA endovascular infections. This signaling pathway represents a logical therapeutic target against persistent MRSA infections. IMPORTANCE Persistent endovascular infections caused by MRSA, including vascular graft infection syndromes and infective endocarditis, are significant and growing public health threats. A particularly worrisome trend is that most MRSA isolates from these patients are “susceptible” in vitro to conventional anti-MRSA antibiotics, such as VAN and daptomycin (DAP), based on Clinical and Laboratory Standards Institute breakpoints. Yet, these antibiotics frequently fail to eliminate these infections in vivo. Therefore, the persistent outcomes in MRSA infections represent a unique and important variant of classic “antibiotic resistance” that is only disclosed during in vivo antibiotic treatment. Given the high morbidity and mortality associated with the persistent infection, there is an urgent need to understand the specific mechanism(s) of this syndrome. In the current study, we demonstrate that a functional intersection between purine biosynthesis and the second messenger c-di-AMP plays an important role in VAN persistence in experimental MRSA endocarditis. Targeting this pathway may represent a potentially novel and effective strategy for treating these life-threatening infections.

Streptococcus mitis/oralis is a fermentative bacterium that relies on lactate dehydrogenase to balance its redox poise and keep glycolysis active. Metabolomic analysis of an in vitro–derived daptomycin-resistant (DAP-R) S. mitis/oralis strain (351-D10) revealed differences in glucose catabolism relative to its DAP-susceptible (DAP-S) parental strain, 351. Metabolic changes associated with the transition to this DAP-R phenotype suggested that inhibiting glycolysis could alter DAP susceptibility. In addition, the strong reliance of S. mitis/oralis on glycolysis for energy and biosynthetic intermediates suggested that inhibiting glycolysis would adversely affect growth and biomass accumulation. To test these hypotheses, we used the lactate dehydrogenase inhibitor oxamic acid (OXA) to assess its efficacy against DAP-S S. mitis/oralis strain 351 during DAP exposures in vitro and ex vivo. As expected, OXA was growth inhibitory to S. mitis/oralis in a dose-dependent manner in vitro; however, it did not alter in vitro DAP susceptibility profiles. In contrast, OXA did prevent the emergence of DAP-R in an ex vivo model of simulated endocardial vegetations. These data suggest that metabolic inhibitors directed against this fermentative bacterium with limited metabolic capabilities could enhance killing and potentially forestall the emergence of DAP resistance.

ABSTRACT In 1980, Farfel and colleagues (NEJM, 1980;303:237–42) provided first evidence for two distinct variants of pseudohypoparathyroidism (PHP) that present with hypocalcemia and impaired parathyroid hormone (PTH)‐stimulated urinary cAMP and phosphate excretion, either in the presence or absence of Albright's hereditary osteodystrophy (AHO). An “abnormal allele” and an “unexpressed allele” were considered as underlying defects, predictions that turned out to be correct for both forms of PHP. Patients affected by the first variant (now referred to as PHP1A) were later shown to be carriers of inactivating mutations involving the maternal GNAS exons encoding Gsα. Patients affected by the second variant (now referred to as PHP1B) were shown in the current study to carry a maternal 3‐kb STX16 deletion, the most frequent cause of autosomal dominant PHP1B, which is associated with loss of methylation at GNAS exon A/B that reduces or abolishes maternal Gsα expression. However, the distinct maternal mutations leading to either PHP1A or PHP1B are disease‐causing only because paternal Gsα expression in the proximal renal tubules is silenced, ie, “unexpressed.” Our findings resolve at the molecular level carefully conducted investigations reported some 41 years ago that had provided first clues for the existence of two distinct PHP variants. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Abstract Background Many subsistence farmers in rural southeastern Tanzania regularly relocate to distant farms in river valleys to tend to crops for several weeks or months each year. While there, they live in makeshift semi-open structures, usually far from organized health systems and where insecticide-treated nets (ITNs) do not provide adequate protection. This study evaluated the potential of a recently developed technology, eave ribbons treated with the spatial repellent transfluthrin, for protecting migratory rice farmers in rural southeastern Tanzania against indoor-biting and outdoor-biting mosquitoes. Methods In the first test, eave ribbons (0.1 m × 24 m each) treated with 1.5% transfluthrin solution were compared to untreated ribbons in 24 randomly selected huts in three migratory communities over 48 nights. Host-seeking mosquitoes indoors and outdoors were monitored nightly (18.00–07.00 h) using CDC light traps and CO2-baited BG malaria traps, respectively. The second test compared efficacies of eave ribbons treated with 1.5% or 2.5% transfluthrin in 12 huts over 21 nights. Finally, 286 farmers were interviewed to assess perceptions about eave ribbons, and their willingness to pay for them. Results In the two experiments, when treated eave ribbons were applied, the reduction in indoor densities ranged from 56 to 77% for Anopheles arabiensis, 36 to 60% for Anopheles funestus, 72 to 84% for Culex, and 80 to 98% for Mansonia compared to untreated ribbons. Reduction in outdoor densities was 38 to 77% against An. arabiensis, 36 to 64% against An. funestus, 63 to 88% against Culex, and 47 to 98% against Mansonia. There was no difference in protection between the two transfluthrin doses. In the survey, 58% of participants perceived the ribbons to be effective in reducing mosquito bites. Ninety per cent were willing to pay for the ribbons, the majority of whom were willing to pay but less than US$2.17 (5000 TZS), one-third of the current prototype cost. Conclusions Transfluthrin-treated eave ribbons can protect migratory rice farmers, living in semi-open makeshift houses in remote farms, against indoor-biting and outdoor-biting mosquitoes. The technology is acceptable to users and could potentially complement ITNs. Further studies should investigate durability and epidemiological impact of eave ribbons, and the opportunities for improving affordability to users.

Abstract Hydroxychloroquine (HCQ) is a well‐established and effective immunomodulatory therapy for systemic lupus erythematosus and other autoimmune diseases. While retinal toxicity is a well‐recognized complication, cardiotoxicity is lesser known. This case consists of a 63‐year‐old Filipina on chronic HCQ treatment that led to severe biventricular hypertrophy, increased filling pressure, systemic and pulmonary hypertension, and elevated brain natriuretic peptide. Genetic testing ruled out lysosomal storage disorders but revealed five rare variants of uncertain significance, including one that was temporarily re‐classified as likely pathogenic. Endomyocardial biopsy demonstrated myeloid bodies admixed with curvilinear bodies, most consistent with a diagnosis of HCQ toxicity. This case illustrates the importance of clinical integration of multiple causes of cardiomyopathy, recognition of HCQ cardiotoxicity, and increased uncertainty in genetic test findings among racial minorities.

Abstract Background Eave ribbons treated with spatial repellents effectively prevent human exposure to outdoor-biting and indoor-biting malaria mosquitoes, and could constitute a scalable and low-cost supplement to current interventions, such as insecticide-treated nets (ITNs). This study measured protection afforded by transfluthrin-treated eave ribbons to users (personal and communal protection) and non-users (only communal protection), and whether introducing mosquito traps as additional intervention influenced these benefits. Methods Five experimental huts were constructed inside a 110 m long, screened tunnel, in which 1000 Anopheles arabiensis were released nightly. Eave ribbons treated with 0.25 g/m2 transfluthrin were fitted to 0, 1, 2, 3, 4 or 5 huts, achieving 0, 20, 40, 60, 80 and 100% coverage, respectively. Volunteers sat near each hut and collected mosquitoes attempting to bite them from 6 to 10 p.m. (outdoor-biting), then went indoors to sleep under untreated bed nets, beside which CDC-light traps collected mosquitoes from 10 p.m. to 6 a.m. (indoor-biting). Caged mosquitoes kept inside the huts were monitored for 24 h-mortality. Separately, eave ribbons, UV–LED mosquito traps (Mosclean) or both the ribbons and traps were fitted, each time leaving the central hut unfitted to represent non-user households and assess communal protection. Biting risk was measured concurrently in all huts, before and after introducing interventions. Results Transfluthrin-treated eave ribbons provided 83% and 62% protection indoors and outdoors respectively to users, plus 57% and 48% protection indoors and outdoors to the non-user. Protection for users remained constant, but protection for non-users increased with eave ribbons coverage, peaking once 80% of huts were fitted. Mortality of mosquitoes caged inside huts with eave ribbons was 100%. The UV–LED traps increased indoor exposure to users and non-users, but marginally reduced outdoor-biting. Combining the traps and eave ribbons did not improve user protection relative to eave ribbons alone. Conclusion Transfluthrin-treated eave ribbons protect both users and non-users against malaria mosquitoes indoors and outdoors. The mosquito-killing property of transfluthrin can magnify the communal benefits by limiting unwanted diversion to non-users, but should be validated in field trials against pyrethroid-resistant vectors. Benefits of the UV–LED traps as an intervention alone or alongside eave ribbons were however undetectable in this study. These findings extend the evidence that transfluthrin-treated eave ribbons could complement ITNs.

Abstract Background Improved surveillance techniques are required to accelerate efforts against major arthropod-borne diseases such as malaria, dengue, filariasis, Zika and yellow-fever. Light-emitting diodes (LEDs) are increasingly used in mosquito traps because they improve energy efficiency and battery longevity relative to incandescent bulbs. This study evaluated the efficacy of a new ultraviolet LED trap (Mosclean) against standard mosquito collection methods. Methods The study was conducted in controlled semi-field settings and in field conditions in rural south-eastern Tanzania. The Mosclean trap was compared to commonly used techniques, namely CDC-light traps, human landing catches (HLCs), BG-Sentinel traps and Suna traps. Results When simultaneously placed inside the same semi-field chamber, the Mosclean trap caught twice as many Anopheles arabiensis as the CDC-light trap, and equal numbers to HLCs. Similar results were obtained when traps were tested individually in the chambers. Under field settings, Mosclean traps caught equal numbers of An. arabiensis and twice as many Culex mosquitoes as CDC-light traps. It was also better at trapping malaria vectors compared to both Suna and BG-Sentinel traps, and was more efficient in collecting mosquitoes indoors than outdoors. The majority of An. arabiensis females caught by Mosclean traps were parous (63.6%) and inseminated (89.8%). In comparison, the females caught by CDC-light traps were 43.9% parous and 92.8% inseminated. Conclusions The UV LED trap (Mosclean trap) was efficacious for sampling Anopheles and Culex mosquitoes. Its efficacy was comparable to and in some instances better than traps commonly used for vector surveillance. The Mosclean trap was more productive in sampling mosquitoes indoors compared to outdoors. The trap can be used indoors near human-occupied nets, or outdoors, in which case additional CO2 improves catches. We conclude that this trap may have potential for mosquito surveillance. However, we recommend additional field tests to validate these findings in multiple settings and to assess the potential of LEDs to attract non-target organisms, especially outdoors.

Abstract Background High hemagglutination inhibition (HAI) and neuraminidase inhibition (NAI) titers are generally associated with reduced influenza risk. While repeated influenza vaccination reduces seroresponse, vaccine effectiveness is not always reduced. Methods During the 2007-2008 influenza season, a randomized, placebo-controlled trial (FLUVACS) evaluated the efficacies of live-attenuated (LAIV) and inactivated influenza vaccines (IIV) among healthy adults aged 18-49 in Michigan; IIV vaccine efficacy (VE) and LAIV VE against influenza disease were estimated at 68% and 36%. Using the principal stratification/VE moderation framework, we analyzed data from this trial to assess how each VE varied by HAI or NAI responses to vaccination observed for vaccinated individuals and predicted counterfactually for placebo recipients. We also assessed how each VE varied with pre-vaccination/baseline variables including HAI titer, NAI titer, and vaccination history. Results IIV VE appeared to increase with Day 30 post-vaccination HAI titer, albeit not significantly (p=0.20 and estimated VE 14.4%, 70.5%, and 85.5% at titer below the assay lower quantification limit, 512, and 4096 (maximum)). Moreover, IIV VE increased significantly with Day 30 post-vaccination NAI titer (p=0.040), with estimated VE zero at titer 10 and 92.2% at highest titer 640. There was no evidence that fold-change in post-vaccination HAI or NAI titer associated with IIV VE (p=0.76, 0.38). For LAIV, there was no evidence that VE associated with post-vaccination or fold-rise HAI or NAI titers (p-values >0.40). For IIV, VE increased with increasing baseline NAI titer in those previously vaccinated, but VE decreased with increasing baseline NAI titer in those previously unvaccinated. In contrast, for LAIV, VE did not depend on previous vaccination or baseline HAI or NAI titer. Conclusions: Future efficacy trials should measure baseline and post-vaccination antibody titers in both vaccine and control/placebo recipients, enabling analyses to better elucidate correlates of vaccine- and natural-protection. Trial registration: ClinicalTrials.gov NCT00538512. October 1, 2007.

Abstract Background Push–pull strategies have been proposed as options to complement primary malaria prevention tools, indoor residual spraying (IRS) and long-lasting insecticide-treated nets (LLINs), by targeting particularly early-night biting and outdoor-biting mosquitoes. This study evaluated different configurations of a push–pull system consisting of spatial repellents [transfluthrin-treated eave ribbons (0.25 g/m2 ai)] and odour-baited traps (CO2-baited BG-Malaria traps), against indoor-biting and outdoor-biting malaria vectors inside large semi-field systems. Methods Two experimental huts were used to evaluate protective efficacy of the spatial repellents (push-only), traps (pull-only) or their combinations (push–pull), relative to controls. Adult volunteers sat outdoors (1830 h–2200 h) catching mosquitoes attempting to bite them (outdoor-biting risk), and then went indoors (2200 h–0630 h) to sleep under bed nets beside which CDC-light traps caught host-seeking mosquitoes (indoor-biting risk). Number of traps and their distance from huts were varied to optimize protection, and 500 laboratory-reared Anopheles arabiensis released nightly inside the semi-field chambers over 122 experimentation nights. Results Push-pull offered higher protection than traps alone against indoor-biting (83.4% vs. 35.0%) and outdoor-biting (79% vs. 31%), but its advantage over repellents alone was non-existent against indoor-biting (83.4% vs. 81%) and modest for outdoor-biting (79% vs. 63%). Using two traps (1 per hut) offered higher protection than either one trap (0.5 per hut) or four traps (2 per hut). Compared to original distance (5 m from huts), efficacy of push–pull against indoor-biting peaked when traps were 15 m away, while efficacy against outdoor-biting peaked when traps were 30 m away. Conclusion The best configuration of push–pull comprised transfluthrin-treated eave ribbons plus two traps, each at least 15 m from huts. Efficacy of push–pull was mainly due to the spatial repellent component. Adding odour-baited traps slightly improved personal protection indoors, but excessive trap densities increased exposure near users outdoors. Given the marginal efficacy gains over spatial repellents alone and complexity of push–pull, it may be prudent to promote just spatial repellents alongside existing interventions, e.g. LLINs or non-pyrethroid IRS. However, since both transfluthrin and traps also kill mosquitoes, and because transfluthrin can inhibit blood-feeding, field studies should be done to assess potential community-level benefits that push–pull or its components may offer to users and non-users.

Abstract Background Anopheles funestus mosquitoes currently contribute more than 85% of ongoing malaria transmission events in south-eastern Tanzania, even though they occur in lower densities than other vectors, such as Anopheles arabiensis. Unfortunately, the species ecology is minimally understood, partly because of difficulties in laboratory colonization. This study describes the first observations of An. funestus swarms in Tanzania, possibly heralding new opportunities for control. Method Using systematic searches by community-based volunteers and expert entomologists, An. funestus swarms were identified in two villages in Ulanga and Kilombero districts in south-eastern Tanzania, starting June 2018. Swarms were characterized by size, height, start- and end-times, presence of copulation and associated environmental features. Samples of male mosquitoes from the swarms were examined for sexual maturity by observing genitalia rotation, species identity using polymerase chain reaction and wing sizes. Results 581 An. funestus (98.1% males (n = 570) and 1.9% (n = 11) females) and 9 Anopheles gambiae sensu lato (s.l.) males were sampled using sweep nets from the 81 confirmed swarms in two villages (Ikwambi in Kilombero district and Tulizamoyo in Ulanga district). Six copulation events were observed in the swarms. Mean density (95% CL) of An. funestus caught/swarm/village/evening was 6.6 (5.9–7.2) in Tulizamoyo and 10.8 (5.8–15.8) in Ikwambi. 87.7% (n = 71) of the swarms were found in Tulizamoyo, while 12.3% (n = 10) were in Ikwambi. Mean height of swarms was 1.7 m (0.9–2.5 m), while mean duration was 12.9 (7.9–17.9) minutes. The PCR analysis confirmed that 100% of all An. funestus s.l. samples processed were An. funestus sensu stricto. Mean wing length of An. funestus males was 2.47 mm (2.0–2.8 mm), but there was no difference between swarming males and indoor-resting males. Most swarms (95.0%) occurred above bare ground, sometime on front lawns near human dwellings, and repeatedly in the same locations. Conclusion This study has demonstrated occurrence of An. funestus swarms for the first time in Tanzania. Further investigations could identify new opportunities for improved control of this dominant malaria vector, possibly by targeting the swarms.

BackgroundWhile malaria transmission in Africa still happens primarily inside houses, there is a substantial proportion of Anopheles mosquitoes that bite or rest outdoors. This situation may compromise the performance of indoor insecticidal interventions such as insecticide-treated nets (ITNs). This study investigated the distribution of malaria mosquitoes biting or resting outside dwellings in three low-altitude villages in south-eastern Tanzania. The likelihood of malaria infections outdoors was also assessed.MethodsNightly trapping was done outdoors for 12 months to collect resting mosquitoes (using resting bucket traps) and host-seeking mosquitoes (using odour-baited Suna® traps). The mosquitoes were sorted by species and physiological states. Pooled samples of Anopheles were tested to estimate proportions infected with Plasmodium falciparum parasites, estimate proportions carrying human blood as opposed to other vertebrate blood and identify sibling species in the Anopheles gambiae complex and An. funestus group. Environmental and anthropogenic factors were observed and recorded within 100 meters from each trapping positions. Generalised additive models were used to investigate relationships between these variables and vector densities, produce predictive maps of expected abundance and compare outcomes within and between villages.ResultsA high degree of fine-scale heterogeneity in Anopheles densities was observed between and within villages. Water bodies covered with vegetation were associated with 22% higher densities of An. arabiensis and 51% lower densities of An. funestus. Increasing densities of houses and people outdoors were both associated with reduced densities of An. arabiensis and An. funestus. Vector densities were highest around the end of the rainy season and beginning of the dry seasons. More than half (14) 58.3% of blood-fed An. arabiensis had bovine blood, (6) 25% had human blood. None of the Anopheles mosquitoes caught outdoors was found infected with malaria parasites.ConclusionOutdoor densities of both host-seeking and resting Anopheles mosquitoes had significant heterogeneities between and within villages, and were influenced by multiple environmental and anthropogenic factors. Despite the high Anopheles densities outside dwellings, the substantial proportion of non-human blood-meals and absence of malaria-infected mosquitoes after 12 months of nightly trapping suggests very low-levels of outdoor malaria transmission in these villages.

ABSTRACT Persistent methicillin-resistant Staphylococcus aureus (MRSA) endovascular infections are life-threatening syndromes with few therapeutic options. The potential impact of bacteriophages on the persistent outcome has not been well studied. In this study, we investigated the role of a novel prophage (ϕSA169) in MRSA persistence by using a lysogen-free clinically resolving bacteremia (RB) isolate and comparing it to a derivative which was obtained by infecting the RB strain with ϕSA169, which has been lysogenized in a clinical persistent MRSA bacteremia (PB) isolate. Similar to the PB isolate, the ϕSA169-lysogenized RB strain exhibited well-defined in vitro and in vivo phenotypic and genotypic signatures related to the persistent outcome, including earlier activation of global regulators (i.e., sigB, sarA, agr RNAIII, and sae); higher expression of a critical purine biosynthesis gene, purF; and higher growth rates accompanied by lower ATP levels and vancomycin (VAN) susceptibility and stronger δ-hemolysin and biofilm formation versus its isogenic parental RB isolate. Notably, the contribution of ϕSA169 in persistent outcome with VAN treatment was confirmed in an experimental infective endocarditis model. Taken together, these results indicate the critical role of the prophage ϕSA169 in persistent MRSA endovascular infections. Further studies are needed to identify the mechanisms of ϕSA169 in mediating the persistence, as well as establishing the scope of impact, of this prophage in other PB strains. IMPORTANCE Bacteriophages are viruses that invade the bacterial host, disrupt bacterial metabolism, and cause the bacterium to lyse. Because of its remarkable antibacterial activity and unique advantages over antibiotics, for instance, bacteriophage is specific for one species of bacteria and resistance to phage is less common than resistance to antibiotics. Indeed, bacteriophage therapy for treating infections due to multidrug-resistant pathogens in humans has become a research hot spot. However, it is also worth considering that bacteriophages are transferable and could cotransfer host chromosomal genes, e.g., virulence and antimicrobial resistance genes, while lysogenizing and integrating into the bacterial chromosome (prophage), thus playing a role in bacterial evolution and virulence. In the current study, we identified a novel prophage, ϕSA169, from a clinical persistent MRSA bacteremia isolate, and we determined that ϕSA169 mediated well-defined in vitro and in vivo phenotypic and genotypic signatures related to the persistent outcome, which may represent a unique and important persistent mechanism(s).

Introduction Ventilator-associated pneumonia (VAP) is a common healthcare-associated infection in the intensive care unit (ICU). Probiotics are defined as live microorganisms that may confer health benefits when ingested. Prior randomised trials suggest that probiotics may prevent infections such as VAP and Clostridioides difficile–associated diarrhoea (CDAD). PROSPECT (Probiotics to Prevent Severe Pneumonia and Endotracheal Colonization Trial) is a multicentre, double-blinded, randomised controlled trial comparing the efficacy of the probiotic Lactobacillus rhamnosus GG with usual care versus usual care without probiotics in preventing VAP and other clinically important outcomes in critically ill patients admitted to the ICU.Methods and analysis The objective of E-PROSPECT is to determine the incremental cost-effectiveness of L. rhamnosus GG plus usual care versus usual care without probiotics in critically ill patients. E-PROSPECT will be performed from the public healthcare payer’s perspective over a time horizon from ICU admission to hospital discharge.We will determine probabilities of in-ICU and in-hospital events from all patients alongside PROSPECT. We will retrieve unit costs for each resource use item using jurisdiction-specific public databases, supplemented by individual site unit costs if such databases are unavailable. Direct costs will include medications, personnel costs, radiology/laboratory testing, operative/non-operative procedures and per-day hospital ‘hoteling’ costs not otherwise encompassed. The primary outcome is the incremental cost per VAP prevented between the two treatment groups. Other clinical events such as CDAD, antibiotic-associated diarrhoea and in-hospital mortality will be included as secondary outcomes. We will perform pre-specified subgroup analyses (medical/surgical/trauma; age; frailty status; antibiotic use; prevalent vs no prevalent pneumonia) and probabilistic sensitivity analyses for VAP, then generate confidence intervals using the non-parametric bootstrapping approach.Ethics and dissemination Study approval for E-PROSPECT was granted by the Hamilton Integrated Research Ethics Board of McMaster University on 29 July 2019. Informed consent was obtained from the patient or substitute decision-maker in PROSPECT. The findings of this study will be published in peer-reviewed journals.Trial registration number NCT01782755; Pre-results.

Methicillin-resistant Staphylococcus aureus (MRSA) regulates resistance to β-lactams via preferential production of an alternative penicillin-binding protein (PBP), PBP2a. PBP2a binds many β-lactam antibiotics with less affinity than PBPs which are predominant in methicillin-susceptible (MSSA) strains. A novel, rather frequent in vitro phenotype was recently identified among clinical MRSA bloodstream isolates, termed “NaHCO3-responsiveness”. This phenotype features β-lactam susceptibility of certain MRSA strains only in the presence of NaHCO3. Two distinct PBP2a variants, 246G and 246E, have been linked to the NaHCO3-responsive and NaHCO3-non-responsive MRSA phenotypes, respectively. To determine the mechanistic impact of PBP2a variants on β-lactam susceptibility, binding profiles of a fluorescent penicillin probe (Bocillin-FL) to each purified PBP2a variant were assessed and compared to whole-cell binding profiles characterized by flow cytometry in the presence vs. absence of NaHCO3. These investigations revealed that NaHCO3 differentially influenced the binding of the fluorescent penicillin, Bocillin-FL, to the PBP2a variants, with binding intensity and rate of binding significantly enhanced in the 246G compared to the 246E variant. Of note, the NaHCO3-β-lactam (oxacillin)-responsive JE2 strain, which natively harbors the 246G variant, had enhanced Bocillin-FL whole-cell binding following exposure to NaHCO3. This NaHCO3-mediated increase in whole-cell Bocillin-FL binding was not observed in the NaHCO3-non-responsive parental strain, COL, which contains the 246E PBP2a variant. Surprisingly, genetic swaps of the mecA coding sites between JE2 and COL did not alter the NaHCO3-enhanced binding seen in JE2 vs. COL. These data suggest that the non-coding regions of mecA may be involved in NaHCO3-responsiveness. This investigation also provides strong evidence that the NaHCO3-responsive phenotype in MRSA may involve NaHCO3-mediated increases in both initial cell surface β-lactam binding, as well as ultimate PBP2a binding of β-lactams.

Abstract Background The Study of Healthcare Personnel with Influenza and other Respiratory Viruses in Israel (SHIRI) prospectively follows a cohort of healthcare personnel (HCP) in two hospitals in Israel. SHIRI will describe the frequency of influenza virus infections among HCP, identify predictors of vaccine acceptance, examine how repeated influenza vaccination may modify immunogenicity, and evaluate influenza vaccine effectiveness in preventing influenza illness and missed work. Methods Cohort enrollment began in October, 2016; a second year of the study and a second wave of cohort enrollment began in June 2017. The study will run for at least 3 years and will follow approximately 2000 HCP (who are both employees and members of Clalit Health Services [CHS]) with routine direct patient contact. Eligible HCP are recruited using a stratified sampling strategy. After informed consent, participants complete a brief enrollment survey with questions about occupational responsibilities and knowledge, attitudes, and practices about influenza vaccines. Blood samples are collected at enrollment and at the end of influenza season; HCP who choose to be vaccinated contribute additional blood one month after vaccination. During the influenza season, participants receive twice-weekly short message service (SMS) messages asking them if they have acute respiratory illness or febrile illness (ARFI) symptoms. Ill participants receive follow-up SMS messages to confirm illness symptoms and duration and are asked to self-collect a nasal swab. Information on socio-economic characteristics, current and past medical conditions, medical care utilization and vaccination history is extracted from the CHS database. Information about missed work due to illness is obtained by self-report and from employee records. Respiratory specimens from self-collected nasal swabs are tested for influenza A and B viruses, respiratory syncytial virus, human metapneumovirus, and coronaviruses using validated multiplex quantitative real-time reverse transcription polymerase chain reaction assays. The hemagglutination inhibition assay will be used to detect the presence of neutralizing influenza antibodies in serum. Discussion SHIRI will expand our knowledge of the burden of respiratory viral infections among HCP and the effectiveness of current and repeated annual influenza vaccination in preventing influenza illness, medical utilization, and missed workdays among HCP who are in direct contact with patients. Trial registration NCT03331991. Registered on November 6, 2017.

Abstract Background Long-lasting insecticide-treated nets and indoor residual spraying protect against indoor-biting and indoor-resting mosquitoes but are largely ineffective for early-biting and outdoor-biting malaria vectors. Complementary tools are, therefore, needed to accelerate control efforts. This paper describes simple hessian ribbons treated with spatial repellents and wrapped around eaves of houses to prevent outdoor-biting and indoor-biting mosquitoes over long periods of time. Methods The eave ribbons are 15 cm-wide triple-layered hessian fabrics, in lengths starting 1 m. They can be fitted onto houses using nails, adhesives or Velcro, without completely closing eave-spaces. In 75 experimental nights, untreated ribbons and ribbons treated with 0.02%, 0.2%, 1.5% or 5% transfluthrin emulsion (spatial repellent) were evaluated against blank controls using two experimental huts inside a 202 m2 semi-field chamber where 500 laboratory-reared Anopheles arabiensis were released nightly. Two volunteers sat outdoors (one/hut) and collected mosquitoes attempting to bite them from 6 p.m. to 10 p.m. (outdoor-biting), then went indoors and slept under bed nets, beside which CDC-light traps collected mosquitoes from 10 p.m. to 6.30 a.m. (indoor-biting). To assess survival, 200 caged mosquitoes were suspended near the huts nightly and monitored for 24 h thereafter. Additionally, field tests were done in experimental huts in a rural Tanzanian village to evaluate treated ribbons (1.5% transfluthrin). Here, indoor-biting was assessed using window traps and Prokopack® aspirators, and outdoor-biting assessed using volunteer-occupied double-net traps. Results Indoor-biting and outdoor-biting decreased > 99% in huts fitted with eave ribbons having ≥ 0.2% transfluthrin. Even 0.02% transfluthrin-treated ribbons provided 79% protection indoors and 60% outdoors. Untreated ribbons however reduced indoor-biting by only 27% and increased outdoor-biting by 18%, though these were non-significant (P > 0.05). Of all caged mosquitoes exposed near treated huts, 99.5% died within 24 h. In field tests, the ribbons provided 96% protection indoors and 84% outdoors against An. arabiensis, plus 42% protection indoors and 40% outdoors against Anopheles funestus. Current prototypes cost ~ 7USD/hut, are made of widely-available hessian and require no specialized expertise. Conclusion Transfluthrin-treated eave ribbons significantly prevented outdoor-biting and indoor-biting malaria vectors and could potentially complement current tools. The technique is simple, low-cost, highly-scalable and easy-to-use; making it suitable even for poorly-constructed houses and low-income groups.

Abstract Background Transfluthrin vapour prevents mosquito bites by disrupting their host-seeking behaviors. We measured the additional benefits of combining transfluthrin-treated sisal decorations and long-lasting insecticidal nets (LLINs) with an aim of extending protection against early evening, indoor-biting malaria vectors when LLINs are ineffective. Methods We investigated the indoor protective efficacy of locally made sisal decorative baskets (0.28 m2) treated with 2.5 ml and 5.0 ml transfluthrin, in terms of mosquito density, exposure to bites and 24 h mortality. Experiments were conducted in experimental huts, located in Lupiro village, Ulanga District, south-eastern Tanzania. Human landing catches (HLC) were used to measure exposure to bites between 19:00–23:00 h. Each morning, at 06:00 h, mosquitoes were collected inside huts and in exit traps and monitored for 24 h mortality. Results Sisal decorative baskets (0.28 m2) treated with 2.5 ml and 5.0 ml transfluthrin deterred three-quarters of Anopheles arabiensis mosquitoes from entering huts (relative rate, RR = 0.26, 95% confidence interval, CI: 0.20–0.34, P < 0.001 and RR= 0.29, 95% CI: 0.22–0.37, P < 0.001, respectively). Both treatments induced a 10-fold increase in 24 h mortality of An. arabiensis mosquitoes (odds ratio, OR = 12.26, 95% CI: 7.70–19.51, P < 0.001 and OR = 18.42, 95% CI: 11.36–29.90, P < 0.001, respectively). Conclusions Sisal decorative items treated with spatial repellents provide additional household and personal protection against indoor biting malaria and nuisance mosquitoes in the early evening, when conventional indoor vector control tools, such as LLINs, are not in use. We recommend future studies to investigate the epidemiological relevance of combining LLINs and transfluthrin decorated baskets in terms of their effect on reduction in malaria prevalence.

Abstract: Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is a common and life-threatening infection that imposes up to 30% mortality even when appropriate therapy is used. Despite in vitro efficacy determined by minimum inhibitory concentration (MIC) breakpoints, antibiotics often fail to resolve these infections in vivo, resulting in persistent MRSA bacteremia. Recently, several genetic, epigenetic, and proteomic correlates of persistent outcomes have been identified. However, the extent to which single variables or their composite patterns operate as independent predictors of outcome or reflect shared underlying mechanisms of persistence is unknown. To explore this question, we employed a tensor-based integration of host transcriptional and cytokine datasets across a well-characterized cohort of patients with persistent or resolving MRSA bacteremia outcomes. This method yielded high correlative accuracy with outcomes and immunologic signatures united by transcriptomic and cytokine datasets. Results reveal that patients with persistent MRSA bacteremia exhibit signals of granulocyte dysfunction, suppressed antigen presentation, and deviated lymphocyte polarization. In contrast, patients with resolving bacteremia heterogeneously exhibit correlates of robust antigen-presenting cell trafficking and enhanced neutrophil maturation corresponding to appropriate T lymphocyte polarization and B lymphocyte response. These results suggest that transcriptional and cytokine correlates of persistent versus resolving bacteremia outcomes are complex and may not be disclosed by conventional modeling. In this respect, a tensor-based integration approach may help to reveal consensus molecular and cellular mechanisms and their biological interpretation.

Antimicrobial susceptibility testing (AST) is routinely used to establish predictive antibiotic resistance metrics to guide the treatment of bacterial pathogens. Recently, a novel phenotype termed “bicarbonate (NaHCO3)-responsiveness” was identified in a relatively high frequency of clinical MRSA strains, wherein isolates demonstrate in vitro “susceptibility” to standard β-lactams (oxacillin [OXA]; cefazolin [CFZ]) in the presence of NaHCO3, and in vivo susceptibility to these β-lactams in experimental endocarditis models. We investigated whether a targeted phenotypic-genotypic screening of MRSA could rule in or rule out NaHCO3 susceptibility upfront. We studied 30 well-characterized clinical MRSA bloodstream isolates, including 15 MIC-susceptible to CFZ and OXA in NaHCO3-supplemented Mueller–Hinton Broth (MHB); and 15 MIC-resistant to both β-lactams in this media. Using a two-tiered strategy, isolates were first screened by standard disk diffusion for susceptibility to a combination of amoxicillin-clavulanate [AMC]. Isolates then underwent genomic sequence typing: MLST (clonal complex [CC]); agr; SCCmec; and mecA promoter and coding region. The combination of AMC disk susceptibility testing plus mecA and spa genotyping was able to predict MRSA strains that were more or less likely to be NaHCO3-responsive in vitro, with a high degree of sensitivity and specificity. Validation of this screening algorithm was performed in six strains from the overall cohort using an ex vivo model of endocarditis. This ex vivo model recapitulated the in vitro predictions of NaHCO3-responsiveness vs. nonresponsiveness above in five of the six strains.