Search

HSV-2 antiviral resistance mainly occurs in immunocompromised patients and especially in HIV-positive individuals receiving long-term antiviral treatment. Those situations can be challenging as few alternatives are available for HSV infection management. To describe clinical and virological significance of two novel potential HSV-2 resistance mutations after treating an obese patient with a pseudotumoral genital HSV-related lesion. Consecutive different antiviral treatments were used: valacyclovir (VACV) then foscarnet (FOS) then topical cidofovir (CDV) and finally imiquimod. Under VACV, genotypic resistance testing revealed a novel mutation within viral thymidine kinase (TK, gene UL23) not previously reported but probably accounting for antiviral resistance: W89G, similar to W88R mutation reported in HSV-1 TK, known to be associated with ACV resistance for HSV-1. Under FOS, while initial mutations were still present, a second genotypic resistance testing performed on persisting lesions showed a novel mutation within viral DNA polymerase (DNA pol, gene UL30): C625R. All three antivirals used in this case are small molecules and pharmacokinetics of VACV, FOS, and CDV have not been evaluated in animals and there are very few studies in human. As small molecules are poorly bound to proteins and distribution volume is increased in obese patients, there is risk of underdosage. This mechanism is suspected to be involved in emergence of resistance mutation and further data is needed to adapt, closely to patient profile, antiviral dosage. This report describes a chronic HSV-2 genital lesion, with resistance to current antivirals and novel mutations within viral TK and DNA pol which may confer antiviral resistance.

To describe the clinical and virological profiles of patients with herpes simplex keratitis (HSK) caused by acyclovir-resistant (ACVMulticenter retrospective case series.HSV-1 resistance to ACV was confirmed using sequencing of genes encoding HSV-1 thymidine kinase (TK) and DNA polymerase (DNA pol). Data were collected on the number of HSK episodes before and after the diagnosis of resistance, ocular findings including the type of HSK, immune status of patients, antiviral treatments, and HSV-1 genotypic resistance profiles.This study evaluated 18 HSK patients (13 male and 5 female, aged 66.8 ± 4.7 years) with ACVHSV-1 resistance to ACV must be suspected in HSK patients with recurrences despite AVP and/or in cases that respond poorly to a suppressive antiviral regimen. Immunocompromised patients and/or those with longstanding disease may be particularly at risk for developing resistance.

Background Lung reactivations of Herpesviridae, herpes simplex virus (HSV) and cytomegalovirus (CMV) have been reported in Covid-19 patients. Whether or not those viral reactivations are more frequent than in other patients is not known. Methods Retrospective monocentric cohort study of 145 patients with severe Covid-19 pneumonia requiring invasive mechanical ventilation and who were tested for HSV and CMV in bronchoalveolar lavage performed during fiberoptic bronchoscopy for ventilator-associated pneumonia suspicion. Rates of HSV and CMV lung reactivations, and HSV bronchopneumonitis were assessed and compared with an historical cohort of 89 patients with severe influenza pneumonia requiring invasive mechanical ventilation. Results Among the 145 Covid-19 patients included, 50% and 42 % had HSV and CMV lung reactivations, respectively; whereas among the 89 influenza patients, 63% and 28% had CMV lung reactivations, respectively. Cumulative incidence of HSV lung reactivation (taking into account extubation and death as competing events) was higher in influenza than in Covid-19 patients (p = 0.03, see figure 1), whereas the rate of HSV bronchopneumonitis was similar in both groups (31% and 25%, respectively). Cumulative incidence of CMV lung reactivation (taking into account extubation and death as competing events) was similar in Covid-19 and influenza patients (p=0.07). Outcomes of patients with HSV or CMV lung reactivations were similar to that of patients without, whatever the underlying conditions, i.e., in Covid-19 patients, in influenza patients, or when all patients were grouped. Estimated cumulative incidence of herpes simplex virus (HSV) lung reactivation, extubation or death in Covid-19 and influenza patients, taking into account only the first event that occurred. p values for differences between Covid-19 and influenza patients were 0.03 for HSV reactivation, 0.53 for death and 0.87 for extubation. Conclusion HSV and CMV lung reactivations are frequent in Covid-19 patients, but not more frequent than in patients with influenza-associated severe pneumonia, despite a higher severity of illness at intensive care unit (ICU) admission of the latter and a longer duration of mechanical ventilation of the former. Although no impact on outcome of HSV and CMV lung reactivations was detected, the effect of antiviral treatment against these Herpesviridae remains to be determined in these patients. Disclosures CHARLES-EDOUARD LUYT, MD PhD, AdvanzPharma: Honoraria|Aerogen: Honoraria|Merck: Honoraria.

BK virus (BKV) belongs to the Polyomaviridae family. It is widespread in adults. Primary infection typically occurs during childhood, without specific symptoms, followed by a state of non-replicative infection in various tissues, with the urogenital tract as the principal site. Immunosuppression promotes reactivation and replication of BKV. After kidney allograft, active infections can cause interstitial nephritis up to graft loss. In hematopoietic stem cell transplant (HSCT) recipients,BKVinfections are associated with hemorrhagic cystitis (HC). The pathogenesis of HC after HSCT represents an interplay between urotoxicity of the conditioning regimen, BKV infection and alloimmune reactions from donor lymphocytes targeting the recipient uroepithelial cells. The diagnosis is based on the quantification of BKV DNA by PCR in urine and blood. The current standard of care for HC is symptomatic, since to date no antiviral drug with proven efficacy against BKV replication has been licensed.

We aimed to characterize the evolution of humoral immune response up to 1 year after SARS-CoV-2 infection in healthcare workers (HCWs) during the first wave of COVID-19 in Paris.Serum samples from 92 HCWs were tested at month 0 (M0), M6, and M12 after SARS-CoV-2 infection for IgG targeting the nucleocapsid (N), IgG targeting the receptor-binding domain (RBD) of spike (S) protein, IgA targeting S, and anti-RBD neutralizing antibodies. After M6, 46 HCWs received a single dose of COVID-19 vaccine.We observed a significant decrease in all SARS-CoV-2 immunologic markers at M6 post-infection: median decreases were 0.26 log binding antibody units/mL (M0: 1.9 (interquartile range (IQR) 1.47-2.27); M6: 1.64 (IQR 1.22-1.92)) for anti-RBD IgG; 4.10 (index) (M0: 4.94 (IQR 2.72-6.82); M6: 0.84 (IQR 0.25-1.55)) for anti-N IgG; 0.64 (index) (M0: 2.50 (IQR 1.18-4.62); M6: 1.86 (IQR 0.85-3.54)) for anti-S IgA; and 24.4% (M0: 66.4 (IQR 39.7-82.5); M6: 42.0 (IQR 16.8-68.8)) inhibition activity for the RBD neutralizing antibodies. Between M6 and M12, anti-RBD IgG level, anti-S IgA index, and anti-RBD neutralizing activity significantly increased among COVID-19 vaccinated HCWs, whereas they remained stable among unvaccinated HCWs. Anti-N IgG index significantly decreased between M6 and M12 among both vaccinated (median: 0.73 (IQR 0.23-1.11) at M6 and 0.52 (IQR 0.20-0.73) at M12) and unvaccinated HCWs (median: 0.79 (IQR 0.21-4.67) at M6 and 0.34 (IQR 0.24-2.78) at M12).A steady decline in the anti-N IgG response was observed during the first year after SARS-CoV-2 infection among HCWs, whereas the anti-RBD IgG and the anti-S IgA responses remained stable and could be enhanced by COVID-19 vaccination.

Resume L’herpes genital constitue la premiere cause d’ulceres genitaux dans le monde. Il est provoque par des virus largement repandus dans la population generale : les virus herpes simplex 1 et 2 (HSV-1 et HSV-2). Cette infection peut affecter la qualite de vie des individus infectes. De plus, l’herpes genital constitue un cofacteur favorisant la transmission du virus de l’immuno-deficience humaine (HIV) par voie sexuelle. La transmission du HSV, au moment de l’accouchement, peut etre responsable de l’herpes neonatal. Le diagnostic de l’herpes genital repose sur deux types de tests biologiques : la detection du genome viral par biologie moleculaire (PCR) dans les ecouvillonnages des voies genitales et la detection d’anticorps specifiques (serologie) pour connaitre le statut immunitaire des patients. La prise en charge therapeutique de l’herpes genital repose essentiellement sur des traitements antiviraux par le valaciclovir, medicament tres actif et tres peu toxique. A ce jour, il n’existe aucun vaccin specifique et l’utilisation du preservatif reste la mesure la plus efficace pour prevenir cette infection virale.

• RT-PCR for SARS-CoV-2′s diagnostic has many false negatives and long turnaround times. • In our study 20% of RT-PCR negative patients had a rapid Sars-CoV2 IgG/IgM positive. • Rapid SARS-CoV2 IgG/IgM may be used as a complementary assay to the RT-PCR. • They can be useful in emergency patient's triage and admission. • They help avoiding to admit a patient infected with SARS-CoV-2 in a COVID-free area.

We report the discovery of a new orthobunyavirus, Cristoli virus, by means of shotgun metagenomics. The virus was identified in an immunodepressed patient with fatal encephalitis. Full-length genome sequencing revealed high-level expression of a virulence factor, possibly explaining the severity of the infection. The patient’s recent history suggests circulation in France.

Human herpes simplex virus 2 (HSV-2) is a globally ubiquitous, slow evolving DNA virus. HSV-2 genomic diversity can be divided into two main groups: an African lineage and worldwide lineage. Competing hypotheses have been put forth to explain the history of HSV-2. HSV-2 may have originated in Africa and then followed the first wave of human migration out of Africa between 50-100 kya. Alternatively, HSV-2 may have migrated out of Africa via the trans-Atlantic slave trade within the last 150-500 years. The lack of HSV-2 genomes from West and Central Africa, combined with a lack of molecular clock signal in HSV-2 has precluded robust testing of these competing hypotheses. Here, we expand the geographic sampling of HSV-2 genomes in order to resolve the geography and timing of divergence events within HSV-2. We analyze 65 newly sequenced HSV-2 genomes collected from primarily West and Central Africa along with 330 previously published genomes sampled over a 47-year period. Evolutionary simulations confirm that the molecular clock in HSV-2 is too slow to be detected using available data. However, phylogeographic analysis indicates that all biologically plausible evolutionary rates would place the ancestor of the worldwide lineage in East Africa, arguing against the trans-Atlantic slave trade as the source of worldwide diversity. The best supported evolutionary rates between 4.2×10−8 and 5.6×10−8 substitutions/site/year suggest a most recent common ancestor for HSV-2 around 90-120 kya and initial dispersal around 21.9-29.3 kya. These dates suggest HSV-2 left Africa during subsequent waves of human migration out of East Africa.

We present the evolutions of the C-BLUE One family of cameras (formerly introduced as C-MORE), a laser guide star oriented wavefront sensor camera family. Within the Opticon WP2 european funded project, which has been set to develop LGS cameras, fast path solutions based on existing sensors had to be explored to provide working-proven cameras to ELT projects ready for the first light schedule. Result of this study, C-BLUE One is a CMOS based camera with 1600x1100 pixels (9um pitch) and 481 FPS refresh rate. It has been developed to answer most of the needs of future laser based adaptive optics systems (LGS) to be deployed on 20-40m-class telescopes as well as on smaller ones. We present the main features of the camera and measured performance in terms of noise, dark current, quantum efficiency and image quality which are the key parameters for the application. The camera has been declined also in fast smaller format (800x600x1500FPS) and large format (3200X2200x250FPS) to cover most of the AO applications., Comment: arXiv admin note: substantial text overlap with arXiv:1910.00374

There have been no significant breakthroughs in infrared imagery since the hybridization of III-V or II-VI narrow-bandgap semiconductors on complementary metal-oxide semiconductor (CMOS) read-out integrated circuits (ROICs). The development of third-generation, linear-mode avalanche photodiode arrays (LmAPDs) using mercury cadmium telluride (MCT) has resulted in a significant sensitivity improvement for short-wave infrared (SWIR) imaging. The first dedicated LmAPD device, called SAPHIRA (320x256/24 microns), was designed by Leonardo UK Ltd specifically for SWIR astronomical applications. In the past decade there has been a significant development effort to make larger LmAPD arrays for low-background astronomy. Larger LmAPD formats for ultra-low noise/flux SWIR imaging, currently under development at Leonardo include a 512 x 512 LmAPD array funded by ESO, MPE and NRC Herzberg, a 1k x 1k array funded by NASA and a 2K x 2K device funded by ESA for general scientific imaging applications. The 2048x2048 pixel ROIC has a pitch of 15 microns, 4/8/16 outputs and a maximum frame rate of 10 Hz. The ROIC characterization is scheduled in the third quarter of 2022, while the first arrays will be fabricated by end-2022. The hybridized arrays will be characterized during end-2022. At this time, First Light Imaging will start the development of an autonomous camera integrating this 2Kx2K LmAPD array, based on the unique experience from the C-RED One camera, the only commercial camera integrating the SAPHIRA SWIR LmAPD array.The detector will be embedded in a compact high vacuum cryostat cooled with low vibration pulse at 50-80K which does not require external pumping. Sub-electron readout noise is expected to be achieved with high multiplication gain. Custom cold filters and beam aperture cold baffling will be integrated in the camera., Comment: 9 pages

This analysis of a randomized clinical trial examines the efficacy of acyclovir for preventing oropharyngeal HSV reactivation among patients who were mechanically ventilated.

International audience; Varicella vaccine meningitis is an uncommon delayed adverse event of vaccination. Varicella vaccine meningitis has been diagnosed in 12 children, of whom 3 were immunocompromised. We now report two additional cases of vaccine meningitis in twice-immunized immunocompetent children and we perform further testing on a prior third case. We used three methods to diagnose or investigate cases of varicella vaccine meningitis, none of which have been used previously on this disease. These include metagenomic next-generation sequencing and cytokine multiplex profiling of cerebrospinal fluid and immunology exome analysis of white blood cells. In one new case, the diagnosis was confirmed by metagenomic next-generation sequencing of cerebrospinal fluid. Both varicella vaccine virus and human herpesvirus 7 DNA were detected. We performed cytokine multiplex profiling on the cerebrospinal fluid of two cases and found ten elevated biomarkers: interferon gamma, interleukins IL-1RA, IL-6, IL-8, IL-10, IL-17F, chemokines CXCL-9, CXCL-10, CCL-2, and G-CSF. In a second new case, we performed immunology exome sequencing on a panel of 356 genes, but no errors were found. After a review of all 14 cases, we concluded that (i) there is no common explanation for this adverse event, but (ii) ingestion of an oral corticosteroid burst 3–4 weeks before onset of vaccine meningitis may be a risk factor in some cases.

International audience; Varicella-zoster virus (VZV) resistance to current antiviral drugs, that all target the viral DNA polymerase, represents a growing concern, notably among immunocompromised patients. Amenamevir, a novel antiviral that inhibits the VZV helicase-primase (HP) complex, is approved in Japan for the treatment of herpes zoster. In this study, we describe the low natural polymorphism of VZV HP complex (interstrain identity >99.7% both at nucleotide and amino acid levels) among 44 VZV clinical isolates. This work enabled to settle the maps of natural polymorphisms of VZV HP complex and to provide the genotypic tools for the monitoring of the emergence of VZV resistance to amenamevir in patients.

With the COVID-19 pandemic, documenting whether health care workers (HCWs) are at increased risk of SARS-CoV-2 contamination and identifying risk factors is of major concern. In this multicenter prospective cohort study, HCWs from frontline departments were included in March and April 2020 and followed for 3 months. SARS-CoV-2 serology was performed at month 0 (M0), M1, and M3 and RT-PCR in case of symptoms. The primary outcome was laboratory-confirmed SARS-CoV-2 infection at M3. Risk factors of laboratory-confirmed SARS-CoV-2 infection at M3 were identified by multivariate logistic regression. Among 1062 HCWs (median [interquartile range] age, 33 [28–42] years; 758 [71.4%] women; 321 [30.2%] physicians), the cumulative incidence of SARS-CoV-2 infection at M3 was 14.6% (95% confidence interval [CI] [12.5; 16.9]). Risk factors were the working department specialty, with increased risk for intensive care units (odds ratio 1.80, 95% CI [0.38; 8.58]), emergency departments (3.91 [0.83; 18.43]) and infectious diseases departments (4.22 [0.92; 18.28]); current smoking was associated with reduced risk (0.36 [0.21; 0.63]). Age, sex, professional category, number of years of experience in the job or department, and public transportation use were not significantly associated with laboratory-confirmed SARS-CoV-2 infection at M3. The rate of SARS-CoV-2 infection in frontline HCWs was 14.6% at the end of the first COVID-19 wave in Paris and occurred mainly early. The study argues for an origin of professional in addition to private life contamination and therefore including HCWs in the first-line vaccination target population. It also highlights that smokers were at lower risk.Trial registration The study has been registered on ClinicalTrials.gov: NCT04304690 first registered on 11/03/2020.

There are concerns about neutralizing antibodies (NAb) potency against the newly emerged VOC202012/01 (UK) and 501Y.V2 (SA) SARS-CoV-2 variants in mRNA-vaccinated subjects and in recovered COVID-19 patients. We used a viral neutralization test with a strict 100% neutralizing criterion on UK and SA clinical isolates in comparison with a globally distributed D614G SARS-CoV-2 strain. In two doses BNT162b2-vaccinated healthcare workers (HCW), despite heterogeneity in neutralizing capacity against the three SARS-CoV-2 strains, most of the sera harbored at least a NAb titer ≥ 1:10 suggesting a certain humoral protection activity either on UK or SA variants. However, six months after mild forms of COVID-19, an important proportion of HCW displayed no neutralizing activity against SA strain. This result supports strong recommendations for vaccination of previously infected subjects.

Keratitis due to Herpes simplex virus (HSK), Varicella-Zoster virus (VZK) and Cytomegalovirus remains a frequent source of concern for many ophthalmologists. They are a frequent cause of emergency consultations at eye care centers and carry the risk of permanent loss of visual acuity or visual quality and/or chronic neurotrophic keratitis, resulting in a significant decrease in the quality of life. HSK and VZK can affect the corneal epithelium, stroma, or endothelium or a combination of layers. In contrast, most cases of CMV keratitis present as isolated endothelitis (CMVE), a clinical entity that has been described within the last 2 decades. These three types of viral keratitis are characterized by a high frequency of recurrences and each new episode increases the risk of sequelae. Hence, ophthalmologists must adapt the treatment to the clinical presentation of each recurrent episode in order to mitigate the immediate consequences of viral replication and the immune response on corneal transparency. In patients with frequent recurrences, preventive long-term antiviral treatment is strongly recommended. However, in some rare cases, continuous exposure to antivirals may promote the emergence of resistant viral strains, which can be difficult to manage. In the future, the introduction of new antiviral drugs, with differing modes of action compared to current medical therapy, could be an alternative until a truly effective preventive solution, such as a vaccine, is available.

Background: With the COVID-19 pandemic, documenting whether health care workers (HCWs) are at increased risk of SARS-CoV-2 contamination and identifying risk factors is of major concern. Methods: In this multicenter prospective cohort study, HCWs from COVID-19 frontline departments were included in March and April 2020 and followed for 3 months. SARS-CoV-2 serology was performed at month 0 (M0), M1, and M3 and RT-PCR in case of symptoms. The primary outcome was laboratory-confirmed SARS-CoV-2 infection (positive serology and/or positive RT-PCR result) at M3. Secondary outcomes were positive serology for SARS-CoV-2 at M0, M1 and M3. Risk factors of laboratory-confirmed SARS-CoV-2 infection at M3 were identified by multivariate logistic regression. Findings: Among 1,062 HCWs (median [interquartile range] age, 33 [28-42] years; 758 [71.4%] women; 321 [30.2%] physicians), the cumulative incidence of SARS-CoV-2 infection at M3 was 14.6% (95% confidence interval [CI] [12.5; 16.9]). Seroprevalence at M0, M1, and M3 was 5.9% [4.7; 7.5], 12.9% [10.9; 15.1] and 13.0% [11.1; 15.2], respectively. Risk factors were the working department specialty, with increased risk for intensive care units (odds ratio 1.80, 95%CI [0.38; 8.58]), emergency departments (3.91 [0.83; 18.43]) and infectious diseases departments (4.22 [0.92; 18.28]); active smoking was associated with reduced risk (0.36 [0.21; 0.63]). Age, sex, professional category, number of years of experience in the job or department, and public transportation use were not significantly associated with laboratory-confirmed SARS-CoV-2 infection at M3. Interpretation: The rate of SARS-CoV-2 infection in frontline HCWs was 14.6% at the end of the first COVID-19 wave in Paris and occurred mainly early. Seroprevalence in May was higher than in the general population. The study argues for an origin of professional in addition to private life contamination and therefore including HCWs in the first-line vaccination target population. It also highlights that smokers were at lower risk. Trial Registration: The study is registered on ClinicalTrials.gov: NCT04304690 Funding Statement: The sponsor of the study was Assistance Publique-Hopitaux de Paris (AP-HP), with study management by URC Pitie-Salpetriere. This study was funded by the French Ministry of Health (Programme Hospitalier de Recherche Clinique) and the French Agency for Research (Fond d’amorcage de l’Agence National pour la Recherche). Declaration of Interests: None to declare. Ethics Approval Statement: The SEROCOV study was approved by the ethics committee (CPP Sud-Ouest et Outre-Mer I, approval no. 2-20-023 id7257) and all participants signed informed consent before inclusion.

There are concerns about neutralizing antibodies’ (NAbs’) potency against severe acute respiratory syndrome coronavirus 2 variants. Despite decreased NAb titers elicited by BNT162b2 vaccine against VOC202012/01 and 501Y.V2 strains, 28/29 healthcare workers (HCWs) had an NAb titer ≥1:10. In contrast, 6 months after coronavirus disease 2019 mild forms, only 9/15 (60%) of HCWs displayed detectable NAbs against 501Y.V2 strain.

We evaluated the utility of the commercial Allplex genital ulcer real-time PCR multiplex assay for detecting Treponema pallidum, herpes simplex virus 1 (HSV-1) and 2 (HSV-2), and Chlamydia trachomatis serovar L (lymphogranuloma venereum [LGV]) DNA in mucosal and genital ulcers in the context of suspected syphilis. In total, 374 documented genital and mucosal ulcers from patients with and without syphilis presenting at several sexually transmitted infection (STI) centers in France from October 2010 to December 2016 were analyzed at the National Reference Center (CNR) for Bacterial STIs at Cochin Hospital in Paris. T. pallidum subsp. pallidum detection results were compared with the final diagnosis based on a combination of clinical examination, serological results, and in-house nested PCR (nPCR). Detections of HSV and LGV were validated against reference methods. We found that 44.6% of the 374 samples tested were positive for T. pallidum subsp. pallidum, 21% for HSV, and 0.8% for LGV. No positive results were obtained for 30.7% of samples, and 4.8% presented coinfections. For T. pallidum subsp. pallidum detection, the overall sensitivity was 80% (95% confidence interval [CI], 76.1 to 84.1%), specificity was 98.8% (95% CI, 97.7 to 99.9%), positive predictive value was 98.8% (95% CI, 97.7 to 99.9%) and negative predictive value was 80.2% (95% CI, 76.2 to 84.2%), with a rate of concordance with the reference method of 92.5% (k = 0.85). This PCR multiplex assay is suitable for T. pallidum subsp. pallidum detection in routine use and facilitates the simultaneous rapid detection of a broad panel of pathogens relevant in a context of suspected syphilis lesions.

International audience; The Delta SARS-CoV-2 variant has a higher viral load than the Beta and the historical variants in nasopharyngeal samples from newly diagnosed COVID-19 patients

France was one of the first countries to be reached by the COVID-19 pandemic. Here, we analyse 196 SARS-Cov-2 genomes collected between Jan 24 and Mar 24 2020, and perform a phylodynamics analysis. In particular, we analyse the doubling time, reproduction number (ℛt) and infection duration associated with the epidemic wave that was detected in incidence data starting from Feb 27. Different models suggest a slowing down of the epidemic in Mar, which would be consistent with the implementation of the national lock-down on Mar 17. The inferred distributions for the effective infection duration andℛtare in line with those estimated from contact tracing data. Finally, based on the available sequence data, we estimate that the French epidemic wave originated between mid-Jan and early Feb. Overall, this analysis shows the potential to use sequence genomic data to inform public health decisions in an epidemic crisis context and calls for further analyses with denser sampling.

Background Data on incidence, clinical presentation and outcomes of ventilator-associated pneumonia (VAP) in patients with severe coronavirus disease 2019 (COVID-19) pneumonia requiring mechanical ventilation (MV) are limited. Methods Case series of patients with COVID-19 pneumonia admitted to a single ICU in France. All consecutive patients requiring MV with RT-PCR–confirmed SARS-CoV-2 infection between March 12th and April 24th, 2020 were included. Frequency, clinical characteristics, responsible pathogens and outcomes of VAP were assessed, and compared to an historical cohort of patients with severe influenza-associated pneumonia requiring MV admitted to the same ICU during the preceding three winter seasons. Results Fifty-four consecutive patients with COVID-19–associated respiratory failure requiring MV were included (median (IQR) age 48 (42–58) years; 74% male; 93% requiring veno-venous ECMO). VAP occurred in 46 (85%) of them (median (IQR) prior MV duration before the first episode, 11 (8–16) days) (Table 1). Pathogens responsible for VAP were predominantly Enterobacteriaceae (72%), and particularly inducible AmpC-cephalosporinase producers (41%), followed by Pseudomonas aeruginosa (35%) (Table 2). Pulmonary infection recurrence and death were observed in 46 (85%) and 17 (31%) patients, respectively. Details on recurrent episodes and pathogens responsible for recurrences are given in Table 3. Most recurrences were relapse (i.e. infection with the same pathogen), with a high proportion occurring during antimicrobial treatment despite its adequacy. Despite a high rate of P. aeruginosa VAP in patients with influenza-associated ARDS, pulmonary infection recurrence rate was significantly lower than in patients with COVID-19. Overall mortality was similar in the two groups. Baseline characteristics of patients Characteristics of first ventilator-associated pneumonia episode Characteristics of recurrent VAP episodes in Covid-19 and influenza patients. Conclusion Patients with severe COVID-19–associated respiratory failure requiring MV had a very high late-onset VAP rate. Inducible AmpC cephalosporinase–producing Enterobacteriaceae and Pseudomonas aeruginosa appeared to be frequently responsible for VAP, with multiple subsequent episodes and difficulties to eradicate the pathogen from the lung. Disclosures All Authors: No reported disclosures

Background Cytomegalovirus (CMV) infection remains a common complication after heart transplantation (HTx). The association between CMV infection and allograft rejection is debated in the era of efficient prophylactic antiviral therapies. Methods This single-center cohort study utilized a highly phenotyped database of HTx recipients (2012-2016). The primary endpoint was the analysis of the association between CMV infection (CMV load ≥500 IU/mL whole blood) and the risk of allograft rejection (cellular rejection ≥1R1B, antibody-mediated rejection ≥pAMR1). Secondary endpoints included the analysis of a higher CMV load threshold (≥10,000 IU/mL) and different risk periods after PCR positivity. A mixed effect logistic regression model with a random intercept was applied. Results were adjusted for important risk factors of rejection. Results Overall, 384 patients were included and 6,388 CMV loads and 3,494 endomyocardial biopsies were analyzed. CMV infections ≥500 IU/mL were diagnosed on 1,223 (19.2%) blood samples from 284 (72.1%) patients and allograft rejections on 246 biopsies (7%) from 149 patients (38.8%). We did find not any association between CMV infection ≥500 IU/mL and rejection (univariable: OR 0.94, 95% CI [0.61, 1.45], p = 0.78, multivariable: OR 0.86, 95% CI [0.55, 1.33], p = 0.85). These results were consistent when analyzing a higher CMV load threshold and different periods of risk, reinforced by internal validation procedures and a posteriori calculation of the power (primary endpoint: power = 0.82, 95% CI [0.79-0.84]) and reproducible across different clinical scenarios. Conclusions CMV infection was not associated with an increased risk of rejection in a contemporary cohort of HTx recipients.

Background The data on incidence, clinical presentation, and outcomes of ventilator-associated pneumonia (VAP) in patients with severe coronavirus disease 2019 (COVID-19) pneumonia requiring mechanical ventilation (MV) are limited. We performed this retrospective cohort study to assess frequency, clinical characteristics, responsible pathogens, and outcomes of VAP in patients COVID-19 pneumonia requiring MV between March 12th and April 24th, 2020 (all had RT-PCR-confirmed SARS-CoV-2 infection). Patients with COVID-19-associated acute respiratory distress syndrome (ARDS) requiring ECMO were compared with an historical cohort of 45 patients with severe influenza-associated ARDS requiring ECMO admitted to the same ICU during the preceding three winter seasons. Results Among 50 consecutive patients with Covid-19-associated ARDS requiring ECMO included [median (IQR) age 48 (42–56) years; 72% male], 43 (86%) developed VAP [median (IQR) MV duration before the first episode, 10 (8–16) days]. VAP-causative pathogens were predominantly Enterobacteriaceae (70%), particularly inducible AmpC-cephalosporinase producers (40%), followed by Pseudomonas aeruginosa (37%). VAP recurred in 34 (79%) patients and 17 (34%) died. Most recurrences were relapses (i.e., infection with the same pathogen), with a high percentage occurring on adequate antimicrobial treatment. Estimated cumulative incidence of VAP, taking into account death and extubation as competing events, was significantly higher in Covid-19 patients than in influenza patients (p = 0.002). Despite a high P. aeruginosa-VAP rate in patients with influenza-associated ARDS (54%), the pulmonary infection recurrence rate was significantly lower than in Covid-19 patients. Overall mortality was similar for the two groups. Conclusions Patients with severe Covid-19-associated ARDS requiring ECMO had a very high late-onset VAP rate. Inducible AmpC-cephalosporinase-producing Enterobacteriaceae and Pseudomonas aeruginosa frequently caused VAP, with multiple recurrences and difficulties eradicating the pathogen from the lung.