Outcome of SARS-CoV-2 infection is linked to MAIT cell activation and cytotoxicity.

Immune system dysfunction is paramount in coronavirus disease 2019 (COVID-19) severity and fatality rate. Mucosal-associated invariant T (MAIT) cells are innate-like T cells involved in mucosal immunity and protection against viral infections. Here, we studied the immune cell landscape, with emphasis on MAIT cells, in cohorts totaling 208 patients with various stages of disease. MAIT cell frequency is strongly reduced in blood. They display a strong activated and cytotoxic phenotype that is more pronounced in lungs. Blood MAIT cell alterations positively correlate with the activation of other innate cells, proinflammatory cytokines, notably interleukin (IL)-18, and with the severity and mortality of severe acute respiratory syndrome coronavirus 2 infection. We also identified a monocyte/macrophage interferon (IFN)-α-IL-18 cytokine shift and the ability of infected macrophages to induce the cytotoxicity of MAIT cells in an MR1-dependent manner. Together, our results suggest that altered MAIT cell functions due to IFN-α-IL-18 imbalance contribute to disease severity, and their therapeutic manipulation may prevent deleterious inflammation in COVID-19 aggravation.

Randomized Trial of Vaccines for Zaire Ebola Virus Disease.

BACKGROUND: Questions remain concerning the rapidity of immune responses and the durability and safety of vaccines used to prevent Zaire Ebola virus disease. METHODS: We conducted two randomized, placebo-controlled trials - one involving adults and one involving children - to evaluate the safety and immune responses of three vaccine regimens against Zaire Ebola virus disease: Ad26.ZEBOV followed by MVA-BN-Filo 56 days later (the Ad26-MVA group), rVSVΔG-ZEBOV-GP followed by placebo 56 days later (the rVSV group), and rVSVΔG-ZEBOV-GP followed by rVSVΔG-ZEBOV-GP 56 days later (the rVSV-booster group). The primary end point was antibody response at 12 months, defined as having both a 12-month antibody concentration of at least 200 enzyme-linked immunosorbent assay units (EU) per milliliter and an increase from baseline in the antibody concentration by at least a factor of 4. RESULTS: A total of 1400 adults and 1401 children underwent randomization. Among both adults and children, the incidence of injection-site reactions and symptoms (e.g., feverishness and headache) was higher in the week after receipt of the primary and second or booster vaccinations than after receipt of placebo but not at later time points. These events were largely low-grade. At month 12, a total of 41% of adults (titer, 401 EU per milliliter) and 78% of children (titer, 828 EU per milliliter) had a response in the Ad26-MVA group; 76% (titer, 992 EU per milliliter) and 87% (titer, 1415 EU per milliliter), respectively, had a response in the rVSV group; 81% (titer, 1037 EU per milliliter) and 93% (titer, 1745 EU per milliliter), respectively, had a response in the rVSV-booster group; and 3% (titer, 93 EU per milliliter) and 4% (titer, 67 EU per milliliter), respectively, had a response in the placebo group (P<0.001 for all comparisons of vaccine with placebo). In both adults and children, antibody responses with vaccine differed from those with placebo beginning on day 14. CONCLUSIONS: No safety concerns were identified in this trial. With all three vaccine regimens, immune responses were seen from day 14 through month 12. (Funded by the National Institutes of Health and others; PREVAC ClinicalTrials.gov number, NCT02876328; EudraCT numbers, 2017-001798-18 and 2017-001798-18/3rd; and Pan African Clinical Trials Registry number, PACTR201712002760250.).

Salvage Therapy Including Foscarnet and Ibalizumab for Multidrug-Resistant Human Immunodeficiency Virus Type 2 Infection.

We evaluated Ibalizumab (IBA)-containing standardized optimized salvage regimen (with or without a 4-week foscarnet induction) in individuals harboring multidrug-resistant human immunodeficiency virus type 2 (HIV-2). Nine were included; 2 achieved virological suppression after foscarnet induction with a sustained suppression at Week 24 after IBA initiation, and an additional individual at Week 24 after Ibalizumab initiation.

Cardiac Adverse Events and Remdesivir in Hospitalized Patients with Coronavirus Disease 2019 (COVID-19): A Post Hoc Safety Analysis of the Randomized DisCoVeRy Trial.

BACKGROUND: We aimed to evaluate the cardiac adverse events (AEs) in hospitalized patients with Coronavirus Disease 2019 (COVID-19) receiving remdesivir plus standard of care (SoC) compared to SoC alone (control), as an association was noted in some cohort studies and disproportionality analyses of safety databases. METHODS: This post-hoc safety analysis is based on data from the multicenter, randomized, open-label, controlled DisCoVeRy trial in hospitalized patients with COVID-19 (NCT04315948). Any first AE occurring between randomization and day 29 in the modified intention-to-treat (mITT) population randomized to either remdesivir or control group was considered. Analysis was performed using Kaplan-Meier survival curves and Kaplan-Meier estimates were calculated for event rates. RESULTS: Cardiac AEs were reported in 46 (11.2%) of 410 and 48 (11.3%) of 423 patients in the mITT population (n = 833) enrolled in the remdesivir and control groups, respectively. The difference between both groups was not significant (HR 1.0, 95% CI 0.7-1.5, p = 0.98), even when evaluating serious and non-serious cardiac AEs separately. The majority of reports in both groups were of arrhythmic nature (remdesivir, 84.8%; control, 83.3%) and were associated with a favorable outcome. There was no significant difference between remdesivir and control groups in the occurrence of different cardiac AE subclasses, including arrhythmic events (HR 1.1, 95% CI: 0.7-1.7, p = 0.68). CONCLUSIONS: Remdesivir treatment was not associated with an increased risk of cardiac AEs, whether serious or not, and regardless of AE severity, compared to control, in patients hospitalized with moderate or severe COVID-19. This is consistent with the results of other randomized controlled trials and meta-analyses.

Modeling SARS-CoV-2 viral kinetics and association with mortality in hospitalized patients from the French COVID cohort.

The characterization of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral kinetics in hospitalized patients and its association with mortality is unknown. We analyzed death and nasopharyngeal viral kinetics in 655 hospitalized patients from the prospective French COVID cohort. The model predicted a median peak viral load that coincided with symptom onset. Patients with age ≥65 y had a smaller loss rate of infected cells, leading to a delayed median time to viral clearance occurring 16 d after symptom onset as compared to 13 d in younger patients (P < 10-4). In multivariate analysis, the risk factors associated with mortality were age ≥65 y, male gender, and presence of chronic pulmonary disease (hazard ratio [HR] > 2.0). Using a joint model, viral dynamics after hospital admission was an independent predictor of mortality (HR = 1.31, P < 10-3). Finally, we used our model to simulate the effects of effective pharmacological interventions on time to viral clearance and mortality. A treatment able to reduce viral production by 90% upon hospital admission would shorten the time to viral clearance by 2.0 and 2.9 d in patients of age <65 y and ≥65 y, respectively. Assuming that the association between viral dynamics and mortality would remain similar to that observed in our population, this could translate into a reduction of mortality from 19 to 14% in patients of age ≥65 y with risk factors. Our results show that viral dynamics is associated with mortality in hospitalized patients. Strategies aiming to reduce viral load could have an effect on mortality rate in this population.

Association Between Increased Linezolid Plasma Concentrations and the Development of Severe Toxicity in Multidrug-Resistant Tuberculosis Treatment.

BACKGROUND: Treatment of multidrug-resistant (MDR) tuberculosis with linezolid is characterized by high rates of adverse events. Evidence on therapeutic drug monitoring to predict drug toxicity is scarce. This study aimed to evaluate the association of linezolid trough concentrations with severe toxicity. METHODS: We retrospectively assessed consecutive patients started on linezolid for MDR tuberculosis between 2011 and 2017. The primary outcome was severe mitochondrial toxicity (SMT) due to linezolid, defined as neurotoxicity or myelotoxicity leading to drug discontinuation. The impact of plasma linezolid trough concentrations >2 mg/L was assessed in multivariate Cox proportional hazards models including time-varying covariates. RESULTS: SMT occurred in 57 of 146 included patients (39%) at an incidence rate of 0.38 per person-year (95% confidence interval, .30-.49). A maximum linezolid trough concentration >2 mg/L was detected in 52 patients (35.6%), while the mean trough concentration was >2 mg/L in 22 (15%). The adjusted hazard ratio for SMT was 2.35 (95% confidence interval, 1.26-4.38; P = .01) in patients with a mean trough concentration >2 mg/L and 2.63 (1.55-4.47; P < .01) for SMT after the first detection of a trough concentration >2 mg/L. In an exploratory analysis, higher maximum trough concentrations were dose-dependently associated with toxicity, while lowering elevated trough concentrations did not restore baseline risk. CONCLUSIONS: Linezolid trough concentrations >2 mg/L are strongly associated with the development of severe treatment-emergent toxicity in patients treated for MDR tuberculosis. Pending further prospective evidence, an individual risk-benefit assessment on the continuation of linezolid treatment is warranted in any patient with trough concentrations >2 mg/L.

Histological Features Associated With Human Mpox Virus Infection in 2022 Outbreak in a Nonendemic Country.

Skin histology of papules and pustules from 5 men having sex with men with mpox infection showed viral intracytoplasmic cytopathic changes, interface dermatitis, marked inflammatory dermic infiltrate including superficial neutrophils and perivascular and periadnexal deep lymphocytes. Histologic description of mpox lesions improves our understanding about clinical presentations and may have some therapeutic implications.

Modelling the potential effectiveness of hepatitis C screening and treatment strategies during pregnancy in Egypt and Ukraine.

BACKGROUND & AIMS: HCV test and treat campaigns currently exclude pregnant women. Pregnancy offers a unique opportunity for HCV screening and to potentially initiate direct-acting antiviral treatment. We explored HCV screening and treatment strategies in two lower middle-income countries with high HCV prevalence, Egypt and Ukraine. METHODS: Country-specific probabilistic decision models were developed to simulate a cohort of pregnant women. We compared five strategies: S0, targeted risk-based screening and deferred treatment (DT) to after pregnancy/breastfeeding; S1, World Health Organization (WHO) risk-based screening and DT; S2, WHO risk-based screening and targeted treatment (treat women with risk factors for HCV vertical transmission [VT]); S3, universal screening and targeted treatment during pregnancy; S4, universal screening and treatment. Maternal and infant HCV outcomes were projected. RESULTS: S0 resulted in the highest proportion of women undiagnosed: 59% and 20% in Egypt and Ukraine, respectively, with 0% maternal cure by delivery and VT estimated at 6.5% and 7.9%, respectively. WHO risk-based screening and DT (S1) increased the proportion of women diagnosed with no change in maternal cure or VT. Universal screening and treatment during pregnancy (S4) resulted in the highest proportion of women diagnosed and cured by delivery (65% and 70%, respectively), and lower levels of VT (3.4% and 3.6%, respectively). CONCLUSIONS: This is one of the first models to explore HCV screening and treatment strategies in pregnancy, which will be critical in informing future care and policy as more safety/efficacy data emerge. Universal screening and treatment in pregnancy could potentially improve both maternal and infant outcomes. IMPACT AND IMPLICATIONS: In the context of two lower middle-income countries with high HCV burdens (Egypt and Ukraine), we designed a decision analytic model to explore five different HCV testing and treatment strategies for pregnant women, with the assumption that treatment was safe and efficacious for use in pregnancy. Assuming direct-acting antiviral treatment during pregnancy would reduce vertical transmission, our findings indicate that the provision of universal (rather than risk-based targeted) screening and treatment would provide the greatest maternal and infant benefits. While future trials are needed to assess the safety and efficacy of direct-acting antivirals in pregnancy and their impact on vertical transmission, there is increasing recognition that the elimination of HCV cannot leave entire subpopulations of pregnant women and young children behind. Our findings will be critical for policymakers when developing improved screening and treatment recommendations for pregnant women.

Proportion of APOBEC3-induced defective HIV DNA after 1†year of dolutegravir + lamivudine simplification in the ANRS 167 LAMIDOL trial.

BACKGROUND: Hypermutated viruses induced by APOBEC3 (apolipoprotein B mRNA-editing, enzyme-catalytic, polypeptide-like 3) proteins comprise some of the defective viruses in the HIV reservoir. Here, we assessed the proportion of APOBEC3-induced defective proviruses in HIV-positive patients before and after receiving dolutegravir + lamivudine dual therapy. METHODS: PBMCs of virologically suppressed patients enrolled in the ANRS 167 LAMIDOL trial, evaluating a switch from triple therapy to dolutegravir + lamivudine, were collected 8 weeks before (W-8) and 48 weeks after (W48) dual-therapy initiation. The Vif and RT regions were subject to next-generation sequencing. Bioinformatic algorithms were developed to identify APOBEC3-defective sequences and APOBEC3-related drug resistance mutations (APOMuts). All hypermutated sequences and those containing at least one stop codon were considered as defective. RESULTS: One hundred and four patients were enrolled (median virological suppression duration: 4.2 years; IQR: 2.0-9.1). Proviral defective reads at W-8 and W48 were detected in Vif in 22% and 29% of patients, respectively, and in RT in 38% and 42% of patients, respectively. At least one APOMut was present in proviruses of 27% and 38% of patients at W-8 and W48, respectively. The ratio of APOMuts/number of potential APOMut sites was significantly higher at W48 (16.5%) than at W-8 (9.8%, P = 0.007). The presence of APOBEC3-defective viruses at W-8 was not associated with HIV total DNA level, nor with the third drug class received prior to switching to dolutegravir + lamivudine, nor with the duration of virological suppression. CONCLUSIONS: Whereas no significant change in the proportion of patients with APOBEC3-defective proviruses was evidenced after 1 year of dolutegravir + lamivudine maintenance, enrichment in APOMuts was observed. Further longer-term studies are needed to assess the other forms of defective viruses with dual-therapy.

Genomic diversity of mpox virus in Paris area (France) during the 2022 outbreak.

In May 2022, several countries reported mpox cases from patients without history of traveling to endemic areas. France was one of the most affected European countries by this outbreak. In this study, the clinical characteristics of mpox cases in France were described, and the genetic diversity of the virus was studied. Patients diagnosed with mpox infection (quantitative polymerase chain reaction ct < 28) between May 21, and July 4, 2022 and between 16th August and 10th September 2022 were included to this study. Twelve amplicons corresponding to the most polymorphic regions of the mpox genome and covering ~30 000 nucleotides were generated and sequenced using the S5 XL Ion Torrent technology to evaluate the genetic diversity of mpox sequences. One hundred and forty-eight patients were diagnosed with mpox-infection. 95% were men, 5% transgender (M-to-F), 50% were taking human immunodeficiency virus (HIV) pre-exposure prophylaxis, and 25% were HIV seropositive. One hundred and sixty-two samples (some patients had two samples) were sequenced and compared to GenBank sequences. Overall, low genetic diversity of mpox sequences was found compared with pre-epidemic Western-African sequences, with 32 distinct mutational patterns. This study provides a first glance at the mutational landscape of early mpox 2022 circulating strains in Paris (France).

Implementation of a centralized pharmacovigilance system in academic pan-European clinical trials: Experience from EU-Response and conect4children consortia.

Setting-up a high quality, compliant and efficient pharmacovigilance (PV) system in multi-country clinical trials can be more challenging for academic sponsors than for companies. To ensure the safety of all participants in academic studies and that the PV system fulfils all regulations, we set up a centralized PV system that allows sponsors to delegate work on PV. This initiative was put in practice by our Inserm-ANRS MIE PV department in two distinct multinational European consortia with 19 participating countries: conect4children (c4c) for paediatrics research and EU-Response for Covid-19 platform trials. The centralized PV system consists of some key procedures to harmonize the complex safety processes, creation of a local safety officer (LSO) network and centralization of all safety activities. The key procedures described the safety management plan for each trial and how tasks were shared and delegated between all stakeholders. Processing of serious adverse events (SAEs) in a unique database guaranteed the full control of the safety data and continuous evaluation of the risk-benefit ratio. The LSO network participated in efficient regulatory compliance across multiple countries. In total, there were 1312 SAEs in EU-Response and 83 SAEs in c4c in the four trials. We present here the lessons learnt from our experience in four clinical trials. We managed heterogeneous European local requirements and implemented efficient communication with all trial teams. Our approach builds capacity for PV that can be used by multiple academic sponsors.

Quantitative Methods Used to Evaluate Impact of Combination HIV Prevention Intervention: A Methodological Systematic Review.

Combination HIV prevention aims to provide the right mix of biomedical, behavioral and structural interventions, and is considered the best approach to curb the HIV pandemic. The impact evaluation of combined HIV prevention intervention (CHPI) provides critical information for decision making. We conducted a systematic review of the literature to map the designs and methods used in these studies. We searched original articles indexed in Web of Science, Scopus and PubMed. Fifty-eight studies assessing the impact of CHPI on HIV transmission were included. Most of the studies took place in Asia or sub-Saharan Africa and were published from 2000 onward. We identified 36 (62.1%) quasi-experimental studies (posttest, pretest-posttest and nonequivalent group designs) and 22 (37.9%) experimental studies (randomized designs). The findings suggest that diverse methods are already rooted in CHPI impact evaluation practices as recommended but should be better reported. CHPI impact evaluation would benefit from more comprehensive approaches.

Assessing complex interventions: a systematic review of outcomes used in randomised controlled trials on STI partner notification in high-income countries.

BACKGROUND: Partner notification interventions are complex and assessing their effectiveness is challenging. By reviewing the literature on the effectiveness of partner notification interventions, our aim was to evaluate the choice, collection, and interpretation of outcomes and their impact on study findings. METHODS: We conducted a systematic review of individual-level randomised controlled trials evaluating the effectiveness of partner notification interventions for bacterial STIs, HIV or sexually transmitted HCV in high-income countries since 2000. Partner notification interventions included assisted patient referral interventions and expedited treatment. The content analysis was carried out through a narrative review. RESULTS: In the 9 studies that met the inclusion criteria, 16 different outcomes were found. In most studies, one or two outcomes assessing partner notification practices were associated with an outcome reflecting STI circulation through index case reinfections. These outcomes assessed the main expected effects of partner notification interventions. However, partner notification is composed of a succession of actions between the intervention on the index case and the testing and/or treatment of the notified partners. Intermediate outcomes were missing so as to better understand levers and barriers throughout the process. Potential changes in participants' sexual behaviour after partner notification, e.g. condom use, were outcomes reported in only two studies assessing interventions including counselling. Most outcomes were collected through interviews, some weeks after the intervention, which might lead to desirability and attrition biases, respectively. Assessment of the effectiveness of partner notification interventions on partner testing/treatment was limited by the collection of data from index cases. Few data describing index cases and their partners were provided in the studies. Additional data on the number and type of exposed partners and the proportion of partners already aware of their infection before being notified would help to interpret the results. CONCLUSIONS: These insights would help to understand why and under what conditions the intervention is considered effective and therefore can be replicated or adapted to other populations and contexts.

Comparative Effectiveness of Interventions to Improve the HIV Continuum of Care and HIV Preexposure Prophylaxis in Kenya: A Model-Based Analysis.

BACKGROUND: In Western Kenya up to one-quarter of the adult population was human immunodeficiency virus (HIV)-infected in 2012. The Ministry of Health, Médecins Sans Frontières, and partners implemented an HIV program that surpassed the 90-90-90 UNAIDS targets. In this generalized epidemic, we compared the effectiveness of preexposure prophylaxis (PrEP) with improving continuum of care. METHODS: We developed a dynamic microsimulation model to project HIV incidence and infections averted to 2030. We modeled 3 strategies compared to a 90-90-90 continuum of care base case: (1) scaling up the continuum of care to 95-95-95, (2) PrEP targeting young adults with 10% coverage, and (3) scaling up to 95-95-95 and PrEP combined. RESULTS: In the base case, by 2030 HIV incidence was 0.37/100 person-years. Improving continuum levels to 95-95-95 averted 21.5% of infections, PrEP averted 8.0%, and combining 95-95-95 and PrEP averted 31.8%. Sensitivity analysis showed that PrEP coverage had to exceed 20% to avert as many infections as reaching 95-95-95. CONCLUSIONS: In a generalized HIV epidemic with continuum of care levels at 90-90-90, improving the continuum to 95-95-95 is more effective than providing PrEP. Continued improvement in the continuum of care will have the greatest impact on decreasing new HIV infections.

Revised Definitions of Tuberculosis Resistance and Treatment Outcomes, France, 2006-2019.

Definitions of resistance in multidrug-resistant tuberculosis (MDR TB) and extensively drug-resistant tuberculosis (XDR TB) have been updated. Pre-XDR TB, defined as MDR TB with additional resistance to fluoroquinolones, and XDR TB, with additional resistance to bedaquiline or linezolid, are frequently associated with treatment failure and toxicity. We retrospectively determined the effects of pre-XDR/XDR TB resistance on outcomes and safety of MDR TB treatment in France. The study included 298 patients treated for MDR TB at 3 reference centers during 2006-2019. Of those, 205 (68.8%) cases were fluoroquinolone-susceptible MDR TB and 93 (31.2%) were pre-XDR/XDR TB. Compared with fluoroquinolone-susceptible MDR TB, pre-XDR/XDR TB was associated with more cavitary lung lesions and bilateral disease and required longer treatment. Overall, 202 patients (67.8%) had favorable treatment outcomes, with no significant difference between pre-XDR/XDR TB (67.7%) and fluoroquinolone-susceptible MDR TB (67.8%; p = 0.99). Pre-XDR/XDR TB was not associated with higher risk for serious adverse events.

Multicenter study on recent portal venous system thrombosis associated with cytomegalovirus disease.

BACKGROUND & AIMS: Recent non-malignant non-cirrhotic portal venous system thrombosis (PVT) is a rare condition. Among risk factors for PVT, cytomegalovirus (CMV) disease is usually listed based on a small number of reported cases. The aim of this study was to determine the characteristics and outcomes of PVT associated with CMV disease. METHODS: We conducted a French multicenter retrospective study comparing patients with recent PVT and CMV disease ("CMV positive"; n = 23) to patients with recent PVT for whom CMV testing was negative ("CMV negative"; n = 53) or unavailable ("CMV unknown"; n = 297). RESULTS: Compared to patients from the "CMV negative" and "CMV unknown" groups, patients from the "CMV positive" group were younger, more frequently had fever, and had higher heart rate, lymphocyte count and serum ALT levels (p ≤0.01 for all). The prevalence of immunosuppression did not differ between the 3 groups (4%, 4% and 6%, respectively). Extension of PVT was similar between the 3 groups. Thirteen out of 23 "CMV positive" patients had another risk factor for thrombosis. Besides CMV disease, the number of risk factors for thrombosis was similar between the 3 groups. Heterozygosity for the prothrombin G20210A gene variant was more frequent in "CMV positive" patients (22%) than in the "CMV negative" (4%, p = 0.01) and "CMV unknown" (8%, p = 0.03) groups. Recanalization rate was not influenced by CMV status. CONCLUSIONS: In patients with recent PVT, features of mononucleosis syndrome should raise suspicion of CMV disease. CMV disease does not influence thrombosis extension nor recanalization. More than half of "CMV positive" patients have another risk factor for thrombosis, with a particular link to the prothrombin G20210A gene variant. LAY SUMMARY: Patients with cytomegalovirus (CMV)-associated portal venous system thrombosis have similar thrombosis extension and evolution as patients without CMV disease. However, patients with CMV-associated portal venous system thrombosis more frequently have the prothrombin G20210A gene variant, suggesting that these entities act synergistically to promote thrombosis.

Epidemiology and control of SARS-CoV-2 epidemics in partially vaccinated populations: a modeling study applied to France.

BACKGROUND: Vaccination is expected to change the epidemiology and management of SARS-CoV-2 epidemics. METHODS: We used an age-stratified compartmental model calibrated to French data to anticipate these changes and determine implications for the control of an autumn epidemic. We assumed vaccines reduce the risk of hospitalization, infection, and transmission if infected by 95%, 60%, and 50%, respectively. RESULTS: In our baseline scenario characterized by basic reproduction number R0=5 and a vaccine coverage of 70-80-90% among 12-17, 18-59, and ≥ 60 years old, important stress on healthcare is expected in the absence of measures. Unvaccinated adults ≥60 years old represent 3% of the population but 43% of hospitalizations. Given limited vaccine coverage, children aged 0-17 years old represent a third of infections and are responsible for almost half of transmissions. Unvaccinated individuals have a disproportionate contribution to transmission so that measures targeting them may help maximize epidemic control while minimizing costs for society compared to non-targeted approaches. Of all the interventions considered including repeated testing and non-pharmaceutical measures, vaccination of the unvaccinated is the most effective. CONCLUSIONS: With the Delta variant, vaccinated individuals are well protected against hospitalization but remain at risk of infection and should therefore apply protective behaviors (e.g., mask-wearing). Targeting non-vaccinated individuals may maximize epidemic control while minimizing costs for society. Vaccinating children protects them from the deleterious effects of non-pharmaceutical measures. Control strategies should account for the changing SARS-CoV-2 epidemiology.

Effect of remdesivir on viral dynamics in COVID-19 hospitalized patients: a modelling analysis of the randomized, controlled, open-label DisCoVeRy trial.

BACKGROUND: The antiviral efficacy of remdesivir in COVID-19 hospitalized patients remains controversial. OBJECTIVES: To estimate the effect of remdesivir in blocking viral replication. METHODS: We analysed nasopharyngeal normalized viral loads from 665 hospitalized patients included in the DisCoVeRy trial (NCT04315948; EudraCT 2020-000936-23), randomized to either standard of care (SoC) or SoC + remdesivir. We used a mathematical model to reconstruct viral kinetic profiles and estimate the antiviral efficacy of remdesivir in blocking viral replication. Additional analyses were conducted stratified on time of treatment initiation (≤7 or >7 days since symptom onset) or viral load at randomization (< or ≥3.5 log10 copies/104 cells). RESULTS: In our model, remdesivir reduced viral production by infected cells by 2-fold on average (95% CI: 1.5-3.2-fold). Model-based simulations predict that remdesivir reduced time to viral clearance by 0.7 days compared with SoC, with large inter-individual variabilities (IQR: 0.0-1.3 days). Remdesivir had a larger impact in patients with high viral load at randomization, reducing viral production by 5-fold on average (95% CI: 2.8-25-fold) and the median time to viral clearance by 2.4 days (IQR: 0.9-4.5 days). CONCLUSIONS: Remdesivir halved viral production, leading to a median reduction of 0.7 days in the time to viral clearance compared with SoC. The efficacy was larger in patients with high viral load at randomization.

MRI Features Associated With the Detection of Microbial Pathogens by CT-Guided Biopsy in Septic Spondylodiscitis.

OBJECTIVE: The aim of this study was to assess the magnetic resonance imaging (MRI) features associated with microbial pathogen detection by computed tomography (CT)-guided biopsy in patients with suspected septic spondylodiscitis. METHODS: For the last 10-year period, we analyzed the medical records of patients who underwent MRI and CT-guided biopsy for suspected septic spondylodiscitis. Clinical characteristics were recorded. The following MRI features were assessed: edema or contrast enhancement of the intervertebral disc, adjacent vertebrae, epidural and paravertebral space, presence of abscess, and paravertebral edema size. A positive biopsy was defined by pathogen identification on bacterial analysis or the presence of granuloma on histology. Predictors of a positive biopsy were assessed with a logistic regression model. RESULTS: We examined data for 61 patients (34 [56%] male; mean age, 59.9 ± 18.0 years); for 35 patients (57%), CT-guided biopsy was positive for a pathogen. The 4 MRI findings significantly associated with a positive biopsy were epiduritis, greater than 50% vertebral endplate edema, loss of intradiscal cleft, and abscess. The size of paravertebral edema was greater with a positive than negative biopsy (median, 15.9 [interquartile range, 11.3-21.3] vs 7.3 [4.6-12.9] mm; p = 0.004). On multivariable analysis, epiduritis was the only independent predictor of a positive biopsy (adjusted odds ratio, 7.4 [95% confidence interval, 1.7-31.4]; p = 0.006). CONCLUSIONS: Epiduritis and the size of paravertebral edema on MRI are associated with detection of a microbial pathogen in suspected septic spondylodiscitis. For patients without these MRI signs, the need for further investigations such as enriched or prolonged cultures, a second CT-guided biopsy, or even surgical biopsy need to be discussed.

Long-Term Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infectiousness Among Three Immunocompromised Patients: From Prolonged Viral Shedding to SARS-CoV-2 Superinfection.

BACKGROUND: Guidelines for stopping coronavirus disease 2019 patient isolation are mainly symptom-based, with isolation for 10 to 20 days depending on their condition. METHODS: In this study, we describe 3 deeply immunocompromised patients, each with different clinical evolutions. We observed (1) the patients' epidemiological, clinical, and serological data, (2) infectiousness using viral culture, and (3) viral mutations accumulated over time. RESULTS: Asymptomatic carriage, symptom resolution, or superinfection with a second severe acute respiratory syndrome coronavirus 2 strain were observed, all leading to prolonged infectious viral shedding for several months. CONCLUSIONS: Understanding underlying mechanisms and frequency of prolonged infectiousness is crucial to adapt current guidelines and strengthen the use of systematic polymerase chain reaction testing before stopping isolation in immunocompromised populations.