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BackgroundLassa fever (LF) is a rodent-borne disease endemic to West Africa. In the absence of licensed therapeutics or vaccines, rodent exclusion from living spaces remains the primary method of preventing LF. Zoonotic surveillance of Lassa virus (LASV), the etiologic agent of LF, can assess the burden of LASV in a region and guide public health measures against LF.MethodsIn this study, we adapted commercially available LASV human diagnostics to assess the prevalence of LASV in peri-domestic rodents in Eastern Sierra Leone. Small mammal trapping was conducted in Kenema district, Sierra Leone between November 2018-July 2019. LASV antigen was detected using a commercially available LASV NP antigen rapid diagnostic test. LASV IgG antibodies against LASV nucleoprotein (NP) and glycoprotein (GP) were tested by adapting a commercially available semi-quantitative enzyme linked immunosorbent assay (ELISA) for detection of mouse-related and rat-related species IgG.FindingsOf the 373 tested specimens, 74 (20%) tested positive for LASV antigen. 40 (11%) specimens tested positive for LASV NP IgG, while an additional 12 (3%) specimens only tested positive for LASV GP IgG. Simultaneous antigen presence and IgG antibody presence was linked inMastomys sp. specimens (p< 0.01), but notRattus sp. specimens (p= 1). Despite the link between antigen presence and IgG antibody presence inMastomys sp., the strength of antigen response did not correlate with the strength of IgG response to either GP IgG or NP IgG.InterpretationThe tools developed in this study can aid in the generation of valuable public health data for rapid field assessment of LASV burden during outbreak investigations and general LASV surveillance.FundingFunding for this work was supported by the National Institute of Allergy and Infectious Diseases National Institute of Health, Department of Health and Human Services under the following grants: International Collaboration in Infectious Disease Research on Lassa fever and Ebola - ICIDR - U19 AI115589, Consortium for Viral Systems Biology - CViSB - 5U19AI135995, West African Emerging Infectious Disease Research Center - WARN-ID - U01AI151812, West African Center for Emerging Infectious Diseases: U01AI151801.

SummaryLassa fever is an acute hemorrhagic fever caused by the zoonotic Lassa virus (LASV). The LASV glycoprotein complex (GPC) mediates viral entry and is the sole target for neutralizing antibodies. Immunogen design is complicated by the metastable nature of recombinant GPCs and the antigenic differences amongst LASV lineages. Despite the sequence diversity of GPC, structures of most lineages are lacking. We present the development and characterization of prefusion-stabilized, trimeric GPCs of LASV lineages II, V, and VI, revealing structural conservation despite sequence diversity. High-resolution structures and biophysical characterization of GPC in complex with GP1-A antibodies reveal their neutralization mechanisms. Finally, we present the isolation and characterization of a novel trimer-preferring neutralizing antibody belonging to the GPC-B competition group with an epitope that spans adjacent protomers and includes the fusion peptide. Our work provides molecular detail information on LASV antigenic diversity and will guide efforts to design pan-LASV vaccines.HighlightsStructural characterization of soluble glycoproteins from four Lassa virus lineages.MAb 12.1F, belonging to the GP1-A cluster, inhibits matriglycan and LAMP-1 binding.GP1-A mAbs show glycan-dependence with 19.7E demonstrating lineage-dependent binding.A novel trimer-preferring NAb S370.7 targets the GPC-B epitope.

Antibodies generated against one dengue serotype can enhance infection of another by a phenomenon called antibody-dependent enhancement (ADE). Additionally, antigenic similarities between Zika and dengue viruses can promote Zika virus infection by way of ADE in vitro using these very same anti-dengue antibodies.

Background Specific details about cardiovascular complications, especially arrhythmias, related to the coronavirus disease of 2019 (COVID‐19) are not well described. Objective We sought to evaluate the incidence and predictive factors of cardiovascular complications and new‐onset arrhythmias in Black and White hospitalized COVID‐19 patients and determine the impact of new‐onset arrhythmia on outcomes. Methods We collected and analyzed baseline demographic and clinical data from COVID‐19 patients hospitalized at the Tulane Medical Center in New Orleans, Louisiana, between March 1 and May 1, 2020. Results Among 310 hospitalized COVID‐19 patients, the mean age was 61.4 ± 16.5 years, with 58,7% females, and 67% Black patients. Black patients were more likely to be younger, have diabetes and obesity. The incidence of cardiac complications was 20%, with 9% of patients having new‐onset arrhythmia. There was no significant difference in cardiovascular outcomes between Black and White patients. A multivariate analysis determined age ≥60 years to be a predictor of new‐onset arrhythmia (OR = 7.36, 95% CI [1.95;27.76], p = .003). D‐dimer levels positively correlated with cardiac and new‐onset arrhythmic event. New onset atrial arrhythmias predicted in‐hospital mortality (OR = 2.99 95% CI [1.35;6.63], p = .007), a longer intensive care unit length of stay (mean of 6.14 days, 95% CI [2.51;9.77], p = .001) and mechanical ventilation duration(mean of 9.08 days, 95% CI [3.75;14.40], p = .001). Conclusion Our results indicate that new onset atrial arrhythmias are commonly encountered in COVID‐19 patients and can predict in‐hospital mortality. Early elevation in D‐dimer in COVID‐19 patients is a significant predictor of new onset arrhythmias. Our finding suggest continuous rhythm monitoring should be adopted in this patient population during hospitalization to better risk stratify hospitalized patients and prompt earlier intervention.

SUMMARYSARS-CoV-2 infection causes a spectrum of clinical outcomes and diverse memory responses. Population studies indicate that viral neutralizing antibody responses are protective, but do not always develop post-infection. Other antiviral antibody effector functions, T-cell responses, or immunity to seasonal coronaviruses (OC43, 229E) have been implicated but not defined in all ages. Here, we identify that children and adult subjects generate polyfunctional antibodies to the spike protein after asymptomatic infection or mild disease, with some subjects developing cellular responses without seroconversion. Diversity in immunity was explained by two clusters distinguished by CD4+ T-cell cytokines, age, and antibodies to seasonal coronaviruses. Post-vaccination neutralizing responses were predicted by specific post-infection immune measures, including IL-2, spike-IgA, OC43-IgG1, 229E-IgM. We confirm a key role for CD4+ T cell cytokines in functionality of anti-spike antibodies, and show that antibody diversity is impacted by age, Th/Th2 cytokine biases, and antibody isotypes to SARS-CoV-2 and seasonal coronaviruses.

Introduction Lassa virus is a priority pathogen for vaccine research and development, however the duration of cellular immunity and protection in Lassa fever (LF) survivors remains unclear. Methods We investigated Lassa virus specific CD8+ T cell responses in 93 LF survivors. Peripheral blood mononuclear cells from these individuals were infected with recombinant vesicular stomatitis virus encoding Lassa virus antigens and virus specific T cell responses were measured after 18-hour incubation. Participants who had undetectable CD8+ T cell response underwent further analysis using a 10-day T cell proliferation assays to evaluate for low T cell precursor frequency. Results Forty-five of the 93 LF survivors did not have a Lassa virus specific CD8+ T cell response. Of those with responses and a known date of onset of LF (N = 11), 9 had LF within the last ten years. Most participants without a measurable CD8+ T cell response were more than 10 years removed from a clinical history of LF (N = 14/16). Fourteen of 21 patients (67%) with undetectable CD8+ T cell response had a measurable Lassa virus specific CD8+ T cell response with the 10-day assay. Discussion Despite reports of strong CD8+ T cell responses during acute Lassa virus infection, circulating Lassa virus-specific CD8+ T cells declined to undetectable levels in most Lassa fever survivors after ten years when evaluated with an 18-hour T cell stimulation. However, when Lassa virus-specific T cells were expanded prior to restimulation, a Lassa virus-specific CD8+ T cell response could be detected in many if the samples that were negative in the 18-hour stimulation assay, suggesting that prolonged cellular immunity does exist in Lassa fever survivors at low frequencies.

Lassa fever (LF) causes multisystem disease and has a fatality rate

Pediatric Lassa fever (LF) usually presents as a nonspecific febrile illness, similar to other endemic diseases in countries like Sierra Leone, where LF is considered to be hyperendemic. The nonspecificity of presentation and lack of research have made it difficult to fully understand best practices for pediatric management. We aim to describe clinical characteristics of hospitalized pediatric patients suspected or diagnosed with LF and assess factors associated with hospital outcomes among those with LF antigen–positive results. We conducted a 7-year retrospective cohort study using routine data for all children younger than 18 years admitted at the Kenema Government Hospital’s LF ward. A total of 292 children with suspected or confirmed LF were analyzed. Overall, mortality was high (21%). Children with antigen-positive results had a high case fatality rate of 63% (P < 0.01). In univariate analyses, children who presented with unexplained bleeding (odds ratio [OR]: 3.58; 95% CI: 1.08–11.86; P = 0.040) and confusion (altered sensorium) (OR: 5.37; 95% CI: 1.34–21.48; P = 0.020) had increased odds of death. Abnormal serum levels of alanine aminotransferase (P = 0.001), creatinine (P = 0.004), and potassium (P = 0.003) were associated with increased likelihood of death in these children. Treatment with ribavirin was not significantly associated with survival (P = 0.916). Our findings provide insights into current pediatric LF clinical presentation and management. More evidence-based, high-quality research in creating predictive algorithms of antigen-positivity and hospital outcomes is needed in the management of pediatric LF.

Objective: Lassa fever (LF), a hemorrhagic fever endemic to West Africa, has an incidence of approximately 500,000 cases per year. This study evaluated hearing loss and other sequelae following LF. Methods: This case–control study enrolled laboratory-confirmed LF survivors, non-LF febrile controls and matched-community controls with no history of LF or recent hospitalization for a febrile illness. Study participants completed a symptom questionnaire. Pure-tone audiometry was completed by a subset of participants. Results: A total of 147 subjects aged 3–66 years (mean, 23.3) were enrolled. LF survivors were significantly more likely to report balance difficulties (55% vs. 20%, p

Lassa virus (LASV) is the causative agent of Lassa fever, an often-fatal hemorrhagic disease that is endemic in West Africa. Seven genetically distinct LASV lineages have been identified. As part of CEPI’s (Coalition for Epidemic Preparedness Innovations) Lassa vaccine development program, we assessed the potential of the human immune system to mount cross-reactive and cross-protective humoral immune responses to antigens from the most prevalent LASV lineages, which are lineages II and III in Nigeria and lineage IV in Sierra Leone. IgG and IgM present in the blood of Lassa fever survivors from Nigeria or Sierra Leone exhibited substantial cross-reactivity for binding to LASV nucleoprotein and two engineered (linked and prefusion) versions of the glycoproteins (GP) of lineages II–IV. There was less cross-reactivity for the Zinc protein. Serum or plasma from Nigerian Lassa fever survivors neutralized LASV pseudoviruses expressing lineage II GP better than they neutralized lineage III or IV GP expressing pseudoviruses. Sierra Leonean survivors did not exhibit a lineage bias. Neutralization titres determined using LASV pseudovirus assays showed significant correlation with titres determined by plaque reduction with infectious LASV. These studies provide guidance for comparison of humoral immunity to LASV of distinct lineages following natural infection or immunization.

Since January 2020, there has been a worldwide pandemic of COVID-19, caused by a novel coronavirus–severe acute respiratory syndrome coronavirus 2. The United States has been particularly affected, with the largest number of confirmed cases in a single country in the world. Healthcare systems for adults as well as children have dealt with challenges. This article will reflect on the experiences of selected children’s hospitals in Seattle, New York City, and New Orleans, three of the “hotspots” in the US and share common aspects and lessons learned from these experiences. This article discusses testing and cohorting of patients, personal protective equipment utilization, limiting workplace exposure, and information sharing.

Background: Cardiac damage is frequently referred to in patients with SARS-CoV-2, is usually diagnosed by enzyme elevations, and is generally thought to be due to underlying coronary artery disease. There are references to cardiomyopathies accompanying coronavirus, but there has been no histologic confirmation. Case report: A previously healthy 17 year male old presented in full cardiac arrest to the emergency department after a 2 day history of headache, dizziness, nausea and vomiting. Autopsy demonstrated an enlarged flabby heart with eosinophilic myocarditis. There was no interstitial pneumonia or diffuse alveolar damage. Postmortem nasopharyngeal swabs detected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) known to cause coronavirus disease 2019 (COVID-19). No other cause for the eosinophilic myocarditis was elucidated. Conclusion: Like other viruses, SARS-CoV-2 may be associated with fulminant myocarditis.

Lassa virus (LASV) is the causative agent of Lassa fever (LF), an often-fatal hemorrhagic disease. LF is endemic in Nigeria, Sierra Leone and other West African countries. Diagnosis of LASV infection is challenged by the genetic diversity of the virus, which is greatest in Nigeria. The ReLASV Pan-Lassa Antigen Rapid Test (Pan-Lassa RDT) is a point-of-care, in vitro diagnostic test that utilizes a mixture of polyclonal antibodies raised against recombinant nucleoproteins of representative strains from the three most prevalent LASV lineages (II, III and IV). We compared the performance of the Pan-LASV RDT to available quantitative PCR (qPCR) assays during the 2018 LF outbreak in Nigeria. For patients with acute LF (RDT positive, IgG/IgM negative) during initial screening, RDT performance was 83.3% sensitivity and 92.8% specificity when compared to composite results of two qPCR assays. 100% of samples that gave Ct values below 22 on both qPCR assays were positive on the Pan-Lassa RDT. There were significantly elevated case fatality rates and elevated liver transaminase levels in subjects whose samples were RDT positive compared to RDT negative.

Background The 2013–2016 Ebola virus disease (EVD) epidemic resulted in more infections and deaths than all prior outbreaks in the 40-year history of this virus combined. This study examines how experiences of EVD infection, and preventive measures such as social distancing, were linked to experiences of stigma and social exclusion among those reintegrating into their communities. Methods Key informant interviews (n = 42) and focus group discussions (n = 27) were conducted in districts with a high prevalence of EVD and representing geographical and ethnic diversity (n = 228 participants). The final sample was composed of adults (52%) and children (48%) who were EVD-infected (46%) and -affected (42%) individuals, and community leaders (12%). Data were coded using a Grounded Theory approach informed by Thematic Content Analysis, and analyzed using NVivo. Interrater reliability was high, with Cohen’s κ = 0.80 or higher. Findings Participants described two main sources of EVD-related stress: isolation from the community because of social distancing and other prevention measures such as quarantine, and stigma related to infected or affected status. Participants linked experiences of social isolation and stigma to significant distress and feelings of ostracization. These experiences were particularly pronounced among children. Sources of support included community reintegration over time, and formal community efforts to provide education and establish protection bylaws. Interpretation This study found that social distancing and EVD-related stigma were each prominent sources of distress among participants. These results suggest that isolation because of infection, and the enduring stigmatization of infected individuals and their families, demand coordinated responses to prevent and mitigate additional psychosocial harm. Such responses should include close engagement with community leaders to combat misinformation and promote community reintegration.

Background Lassa virus (LASV), the cause of the acute viral hemorrhagic illness Lassa fever (LF), is endemic in West Africa. Infections in humans occur mainly after exposure to infected excrement or urine of the rodent-host, Mastomys natalensis. The prevalence of exposure to LASV in Sierra Leone is crudely estimated and largely unknown. This cross-sectional study aimed to establish a baseline point seroprevalence of IgG antibodies to LASV in three administrative districts of Sierra Leone and identify potential risk factors for seropositivity and LASV exposure. Methodology and principal findings Between 2015 and 2018, over 10,642 participants from Kenema, Tonkolili, and Port Loko Districts were enrolled in this cross-sectional study. Previous LASV and LF epidemiological studies support classification of these districts as “endemic,” “emerging,” and “non-endemic”, respectively. Dried blood spot samples were tested for LASV antibodies by ELISA to determine the seropositivity of participants, indicating previous exposure to LASV. Surveys were administered to each participant to assess demographic and environmental factors associated with a higher risk of exposure to LASV. Overall seroprevalence for antibodies to LASV was 16.0%. In Kenema, Port Loko, and Tonkolili Districts, seroprevalences were 20.1%, 14.1%, and 10.6%, respectively. In a multivariate analysis, individuals were more likely to be LASV seropositive if they were living in Kenema District, regardless of sex, age, or occupation. Environmental factors contributed to an increased risk of LASV exposure, including poor housing construction and proximity to bushland, forested areas, and refuse. Conclusions and significance In this study we determine a baseline LASV seroprevalence in three districts which will inform future epidemiological, ecological, and clinical studies on LF and the LASV in Sierra Leone. The heterogeneity of the distribution of LASV and LF over both space, and time, can make the design of efficacy trials and intervention programs difficult. Having more studies on the prevalence of LASV and identifying potential hyper-endemic areas will greatly increase the awareness of LF and improve targeted control programs related to LASV.

Many countries in sub-Saharan Africa have experienced lower COVID-19 caseloads and fewer deaths than countries in other regions worldwide. Under-reporting of cases and a younger population could partly account for these differences, but pre-existing immunity to coronaviruses is another potential factor. Blood samples from Sierra Leonean Lassa fever and Ebola survivors and their contacts collected before the first reported COVID-19 cases were assessed using enzyme-linked immunosorbent assays for the presence of antibodies binding to proteins of coronaviruses that infect humans. Results were compared to COVID-19 subjects and healthy blood donors from the United States. Prior to the pandemic, Sierra Leoneans had more frequent exposures than Americans to coronaviruses with epitopes that cross-react with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), SARS-CoV, and Middle Eastern respiratory syndrome coronavirus (MERS-CoV). The percentage of Sierra Leoneans with antibodies reacting to seasonal coronaviruses was also higher than for American blood donors. Serological responses to coronaviruses by Sierra Leoneans did not differ by age or sex. Approximately a quarter of Sierra Leonian pre-pandemic blood samples had neutralizing antibodies against SARS-CoV-2 pseudovirus, while about a third neutralized MERS-CoV pseudovirus. Prior exposures to coronaviruses that induce cross-protective immunity may contribute to reduced COVID-19 cases and deaths in Sierra Leone.

ImportanceReal-world data are needed to assess incidence and factors associated with breakthrough SARS-CoV-2 infections following vaccination.ObjectiveEstimate incidence of breakthrough infections and assess associations with risk factors using self-reported data from a large NC population sample.DesignProspective observational cohort study utilizing daily online survey data to capture information about COVID-19 symptoms, testing, and vaccination status.SettingSix health care systems in North Carolina with data collected between January 15, 2021 and September 24, 2021.ParticipantsAdult study participants who reported full vaccination with a COVID-19 mRNA or J&J non-replicating viral vector vaccine (n =16,020).ExposuresPotential community exposure to SARS-CoV-2.Main Outcome and MeasuresSelf-reported breakthrough infection.ResultsSARS-CoV-2 infection after vaccination was self-reported in 1.9% of participants, with an incidence rate of 7.3 per 100,000 person-years. Younger age (45-64 vs. 18-44: HR (95% CI) = 0.65 (0.51 - 0.82); 65+ vs. 18-44: HR (95% CI) = 0.59 (0.39 - 0.90)), and vaccination with J&J Ad26.COV2.S were associated with a higher risk of breakthrough infection compared to vaccination with Pfizer BNT162b2 (Ad26.COV2.S vs. BNT162b2: HR (95% CI) = 2.23 (1.40 - 3.56)), while participants vaccinated with mRNA-1273 (mRNA-1273 vs. BNT162b2: HR (95% CI) = 0.69 (0.50 – 0.96) and those residing in urban counties experienced a lower rate of SARS-CoV-2 breakthrough infection compared with those from suburban (HR (95% CI) = 1.39 (1.01 – 1.90) or rural (HR (95% CI) = 1.57 (1.16 – 2.11) counties. There was no significant association between breakthrough infection and participant sex, race, healthcare worker status, prior COVID-19 infection, routine mask use, or overall vaccination rate in the county of residence.Conclusions and RelevanceThis NC community-based observational study showed that the proportion of the cohort who self-report breakthrough SARS-CoV-2 infections was 7.3 events per 100,000 person-years. Younger adults, those vaccinated with J&J Ad26.COV2.S, and those residing in suburban or rural counties were at higher risk of breakthrough infections and should be targeted for additional risk mitigation strategies to decrease community transmission.Trial RegistrationThe COVID-19 Community Research Partnership is listed in clinicaltrials.gov (NCT04342884).Key PointsQuestionWhat are the characteristics of those with breakthrough infections after SARS-CoV-2 vaccination in North CarolinaãFindingsIn this NC-based observational study of 16,020 participants, 1.9% self-reported a positive SARS-CoV-2 viral test at least 2 weeks following full vaccination, reflecting an event rate of 7.3 infections per 100,000 person years. Rates were higher among younger participants, participants from more rural areas in North Carolina, and those vaccinated with J&J Ad26.COV2.S.MeaningOur results show a relatively low rate of COVID-19 infection following full vaccination. Younger adults and those vaccinated with J&J Ad26.COV2.S should be targeted for additional risk mitigation strategies.

Serologic testing of residual blood samples from 812 children from a hospital in New Orleans, LA, between March and May 2020, demonstrated a SARS-CoV-2 seroprevalence of 6.8% based on S and N protein IgG; Black and Hispanic children, and children living in zip codes with lower household incomes were over-represented.

Background The West African Ebola epidemic of 2013–2016 killed nearly 4,000 Sierra Leoneans and devastated health infrastructure across West Africa. Changes in health seeking behavior (HSB) during the outbreak resulted in dramatic underreporting and substantial declines in hospital presentations to public health facilities, resulting in an estimated tens of thousands of additional maternal, infant, and adult deaths per year. Sierra Leone’s Kenema District, a major Ebola hotspot, is also endemic for Lassa fever (LF), another often-fatal hemorrhagic disease. Here we assess the impact of the West African Ebola epidemic on health seeking behaviors with respect to presentations to the Kenema Government Hospital (KGH) Lassa Ward, which serves as the primary health care referral center for suspected Lassa fever cases in the Eastern Province of Sierra Leone. Methodology/Principal findings Presentation frequencies for suspected Lassa fever presenting to KGH or one of its referral centers from 2011–2019 were analyzed to consider the potential impact of the West African Ebola epidemic on presentation patterns. There was a significant decline in suspected LF cases presenting to KGH following the epidemic, and a lower percentage of subjects were admitted to the KGH Lassa Ward following the epidemic. To assess general HSB, a questionnaire was developed and administered to 200 residents from 8 villages in Kenema District. Among 194 completed interviews, 151 (78%) of respondents stated they felt hospitals were safer post-epidemic with no significant differences noted among subjects according to religious background, age, gender, or education. However, 37 (19%) subjects reported decreased attendance at hospitals since the epidemic, which suggests that trust in the healthcare system has not fully rebounded. Cost was identified as a major deterrent to seeking healthcare. Conclusions/Significance Analysis of patient demographic data suggests that fewer individuals sought care for Lassa fever and other febrile illnesses in Kenema District after the West African Ebola epidemic. Re-establishing trust in health care services will require efforts beyond rebuilding infrastructure and require concerted efforts to rebuild the trust of local residents who may be wary of seeking healthcare post epidemic., Author summary The West African Ebola epidemic of 2013–2016 killed nearly 4,000 Sierra Leoneans and devastated health infrastructure. There is limited information regarding the effects of the epidemic on health seeking behavior. Lassa fever is clinically similar to Ebola and is prevalent in Kenema District, located in the Eastern Province of Sierra Leone. There was a significant decline in the number of individuals seeking care for suspected Lassa fever following the epidemic. Responses to a questionnaire completed by 194 Sierra Leonean residents suggested that confidence in the healthcare system was not fully restored. Cost was identified as a major deterrent to seeking healthcare. Additional community sensitization is needed to convey the need, and importance, of seeking care for Lassa fever.

Recently there have been several reports of SARS-CoV2 "breakthrough" infections that have occurred in recipients of the FDA approved SAR-CoV-2 vaccines. The use of the term "breakthrough" infections implies that the virus broke through a protective barrier provided by the vaccine. However, is this what happened in these cases? In most cases, the answer is no, and this answer lies in the fundamental understanding of the mucosal immune system. Here we suggest a more precise definition of what a true breakthrough case is.

Monoclonal antibodies can mediate protection against Ebola virus (EBOV) infection through direct neutralization as well as through the recruitment of innate immune effector functions. However, the antibody functional response following survival of acute EBOV disease has not been well characterized. In this study, serum antibodies from Ebola virus disease (EVD) survivors from Sierra Leone were profiled to capture variation in overall subclass/isotype abundance, neutralizing activity, and innate immune effector functions. Antibodies from EVD survivors exhibited robust innate immune effector functions, mediated primarily by IgG1 and IgA1. In conclusion, development of functional antibodies follows survival of acute EVD., The humoral immune response in human survivors of Ebola virus disease includes the development of neutralizing antibodies and polyfunctional IgG1 and IgA antibodies that can mediate effector functions against the Ebola virus glycoprotein via multiple innate immune effector cell types.

The American Society for Tropical Medicine and Hygiene recently inaugurated an award for the best clinical research article published in the society’s journal in the previous year. This article summarizes both the process of selecting the winner and several themes that stood out in those articles which rose to the top for consideration. Themes of note included the importance of doing clinical research outside of referral centers, the complexity that must be considered when implementing interventions, incorporation of both ends of the age spectrum into studies, and considering cost-effectiveness and opportunity cost of interventions.

The neglected tropical diseases Zika, Ebola, and Lassa fever (LF) have all been noted to cause some degree of hearing loss (HL). Hearing loss is a chronic disability that can lead to a variety of detrimental effects, including speech and language delays in children, decreased economic productivity in adults, and accelerated cognitive decline in older adults. The objective of this review is to summarize what is known regarding HL secondary to these viruses. Literature for this review was gathered using the PubMed database. Articles were excluded if there were no data of the respective viruses, postinfectious complications, or conditions related to survivorship. A total of 50 articles were included in this review. Fourteen articles discussing Zika virus and subsequent complications were included. Across these studies, 56 (21.2%) of 264 Zika-infected individuals were found to have HL. Twenty-one articles discussing Ebola virus and subsequent complications were included, with 190 (5.7%) of 3,350 Ebola survivors found to have HL. Fifteen additional articles discussing LF and subsequent complications were included. Of 926 individuals with LF, 79 (8.5%) were found to have HL. These results demonstrate a relationship between HL and infection. The true prevalence is likely underestimated, however, because of lack of standardization of reporting and measurement. Future studies of viral sequelae would benefit from including audiometric evaluation. This information is critical to understanding pathophysiology, preventing future cases of this disability, and improving quality of life after survival of infection.

Background Sepsis is the leading cause of global mortality, and it is frequently attributed to lower respiratory tract infections and subsequent acute respiratory distress syndrome (ARDS). Patients from sub-Saharan Africa (sSA) are underrepresented in existing studies of sepsis, and little is known about ARDS in sSA. Severe respiratory distress (SRD) is a surrogate for ARDS defined by the WHO as O2 saturation 30 breaths/minute and a systolic blood pressure >90 mmHg plus suspected infection in the absence of cardiac failure. In the context of the current COVID-19 pandemic, a better understanding of SRD in sSA is urgently needed. In this study, we aimed to determine the prevalence, clinical characteristics, and in-hospital mortality of adults with SRD in sSA. Methods We analyzed pooled individual-level data from 16 studies of hospitalized patients conducted in 6 countries throughout sSA from 2009 to 2019. We used multiple imputation with chained equations with 10 iterations to impute missing data. We performed multivariable logistic regression to estimate associations between patient vital signs, laboratory studies, SRD, and in-hospital mortality. We characterized factors associated with in-hospital mortality in the subset of patients with SRD. Results The pooled data included 7385 patients with a median age of 37 years, of whom 3584 (49%) were women, 2282 (31%) were living with HIV, 3190 (43%) had a known acute infection, and 946 (13%) had SRD. The mortality for the total population and for patients with SRD was 15% and 22%, respectively. Older age, lower temperature, increased heart rate, increased respiratory rate, decreased oxygen saturation, Glasgow Coma Scale score

Background Following the West African Ebola virus disease (EVD) outbreak of 2013–2016 and more recent EVD outbreaks in the Democratic Republic of Congo, thousands of EVD survivors are at-risk for sequelae including uveitis, which can lead to unremitting inflammation and vision loss from cataract. Because of the known risk of Ebola virus persistence in ocular fluid and the need to provide vision-restorative, safe cataract surgery, the Ebola Virus Persistence in Ocular Tissues and Fluids (EVICT) Study was implemented in Sierra Leone. During implementation of this multi-national study, challenges included regulatory approvals, mobilization, community engagement, infection prevention and control, and collaboration between multiple disciplines. In this report, we address the multifacted approach to address these challenges and the impact of implementation science research to address an urgent clinical subspecialty need in an outbreak setting. Methodology/Principal findings Given the patient care need to develop a protocol to evaluate ocular fluid for Ebola virus RNA persistence prior to cataract surgery, as well as protocols to provide reassurance to ophthalmologists caring for EVD survivors with cataracts, the EVICT study was designed and implemented through the work of the Ministry of Health, Sierra Leone National Eye Programme, and international partnerships. The EVICT study showed that all 50 patients who underwent ocular fluid sampling at 19 and 34 months, respectively, tested negative for Ebola virus RNA. Thirty-four patients underwent successful cataract surgery with visual acuity improvement. Here we describe the methodology for study implementation, challenges encountered, and key issues that impacted EVD vision care in the immediate aftermath of the EVD outbreak. Key aspects of the EVICT study included defining the pertinent questions and clinical need, partnership alignment with key stakeholders, community engagement with EVD survivor associations, in-country and international regulatory approvals, study site design for infection prevention and control, and thorough plans for EVD survivor follow-up care and monitoring. Challenges encountered included patient mobilization owing to transportation routes and distance of patients in rural districts. Strong in-country partnerships and multiple international organizations overcame these challenges so that lessons learned could be applied for future EVD outbreaks in West and Central Africa including EVD outbreaks that are ongoing in Guinea and Democratic Republic of Congo. Conclusions/Significance The EVICT Study showed that cataract surgery with a protocol-driven approach was safe and vision-restorative for EVD survivors, which provided guidance for EVD ophthalmic surgical care. Ophthalmologic care remains a key aspect of the public health response for EVD outbreaks but requires a meticulous, yet partnered approach with international and local in-country partners. Future efforts may build on this framework for clinical care and to improve our understanding of ophthalmic sequelae, develop treatment paradigms for EVD survivors, and strengthen vision health systems in resource-limited settings.

Lassa fever is a viral hemorrhagic illness with a case fatality rate for hospitalized patients as high as 69%. Identifying cases before they progress to serious illness can lead to earlier treatment and improved clinical outcomes. Three existing clinical prediction tools were evaluated on their ability to predict the in-hospital mortality in Lassa fever: the quick Sequential Organ Failure Assessment (qSOFA), the Modified Early Warning System (MEWS), and the Universal Vital Assessment (UVA). This was a retrospective cohort study of patients admitted to the dedicated Lassa fever ward of the Kenema Government Hospital in Sierra Leone between May 2013 and December 2019. Data among three serology groups were analyzed: Lassa antigen-positive (Ag+) regardless of IgM status, Lassa Ag- and IgM+, and Lassa Ag- and IgM- cases. There were 123 cases of suspected Lassa fever included in this study. Abnormalities in respiratory rate, oxygenation status, mental status, and serum markers of kidney and liver dysfunction were more likely seen in the Ag+ group, which had an in-hospital mortality of 85.7%. For the Lassa Ag+ group, the sensitivity and positive predictive value of qSOFA ≥ 2 was 70.6% and 92.3%, MEWS ≥ 5 was 96.9% and 86.1%, and UVA ≥ 5 was 60.0% and 100.0%. The MEWS and UVA scores show potential for use in Lassa fever, but there is opportunity for future development of a tool that includes the clinical and laboratory markers specific to Lassa fever.

Survivors of Ebola virus disease (EVD) have reported a wide range of symptoms following recovery from infection. These long-term sequelae, collectively termed post-Ebola syndrome (PES), can significantly impact the daily lives of EVD survivors, yet little is known about the underlying mechanism of PES pathogenesis. Antibodies against Ebola virus provide protection against infection through both neutralization and recruitment of innate immune effector functions via the antibody Fc region, yet persistent antibody-mediated inflammation may contribute to PES manifestations. To investigate the potential role that virus-specific antibodies have in PES, we analyzed the antibody immune profiles in a cohort of EVD survivors and household contacts that had been previously characterized for clinical sequelae. Antibodies isolated from survivors an average of 2.5 years after recovery were measured for induction of Fc-mediated innate effector function against the immunodominant antigen Ebola glycoprotein-coated targets. We found that antibodies in asymptomatic EVD survivors were qualitatively different from survivors experiencing musculoskeletal and gastrointestinal manifestations of PES. Specifically, antibodies from asymptomatic individuals induced higher levels of antibody-dependent complement deposition and monocyte-mediated phagocytosis, but not neutrophil-mediated phagocytosis, and differed in NK cell activation profiles compared with individuals with PES. Together, these data suggest that the development of qualitatively different antibodies may shape susceptibility to/protection from the development of PES and may help identify potential therapeutic targets for EVD survivors suffering from PES. Supported by Washington State University, College of Veterinary Medicine

SARS CoV-2 in children or special populations post-infection has not been well studied. Asthma is a heterogenous disease marked by chronic airway inflammation; triggers include cockroaches (CRA), and other inhaled irritants. Asthma also has links to viral infections like respiratory syncytial virus (RSV). Additionally, some with moderate to severe asthma are more likely to be hospitalized with COVID. T cells play key roles in asthma and control of viruses such; however, there is limited information connecting T cell responses in people with asthma to viral infections. We aimed to evaluate T cells and antibodies in an asthma confirmed cohort. Thirty-five children aged 5–17 years were included. We measured SARS CoV-2 spike (S) and Nucleoprotein (N) plasma antibody responses or effector functions and CD4, CD8 T cells specific to CRA or peptide pools made from RSV, S and N antigen using an activation induced markers (AIM) assay. Surprisingly, in this population many CD4 and CD8 T-cell AIM responses to S, N, CRA, and RSV were significantly associated, particularly for CD8 T-cells (Spearmans r = 0.57–0.76) and the restimulation antigens CRA and RSV. N-specific CD4 AIM was the only immune measure to correlate to a recent asthma attack within a month of the blood collection visit, though anti-N antibodies, CD4 AIM to CRA, RSV or CD8 AIM to CRA, RSV, or N antigens also correlated with asthmatic outcomes (e.g., ER visits, night waking from symptoms, etc.) whereas allergen specific IgE or anti-S IgG did not. Taken together these results indicate an immunological association between viral infection and asthma, broadly allowing for the conjecture that viral infections, in particular RSV and SARS-CoV-2 could act together as possible triggers of asthma.