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Human papillomavirus (HPV) infections drive one in twenty new cancer cases. Despite the potential for improving treatment, screening, and vaccination strategies, little is known as to why most HPV infections clear spontaneously within two years. To untangle the dynamics of these non-persisting infections, we performed a combined quantitative analysis of virological, immunological, and clinical data from an original longitudinal cohort of 189 women with high temporal resolution. We find that HPV viral load reaches a plateau within two months, and clears within a median time of 14 months. Furthermore, we identify immune correlates associated with infection clearance, especially TCR-gamma-delta cells. Our results open new perspectives for understanding the frontier between acute and chronic infections and for controlling HPVassociated diseases.

ObjectiveTo determine if the use of menstrual cups rather than tampons is associated with more or less health risk.DesignAnalysing biological, demographic, and behavioural data in a cohort of women who reported using mostly tampons (n = 81) or menstrual cups (n = 22).SettingA cross-sectional analysis using the inclusion data of a single centre longitudinal study.Population149 women from 18 to 25 years old living in the area of Montpellier (France) who reported having at least one new sexual partner over the last year.MethodsStatistical modelling (mainly binomial regression models and factor analyses of mixed data).Main Outcome MeasuresSelf-reported data from questionnaires (fungal infection, urinary tract infection, stress level) and biological data (HPV screening, vaginal microbiota profiling, circulating antibodies titration, and local cytokine concentrations).ResultsWe identify an increased risk of reporting fungal infections for women using menstrual cups over tampons. We do not detect significant differences in terms of vaginal microbiota composition or local cytokines expression profile but find that women fall into two different clusters in a factor analysis of mixed data depending on the type of menstrual product they use more (cups or tampons).ConclusionsThese results point to potential health risks in the use of menstrual cups and differences in local vaginal environments. In-depth studies are needed to better understand potential associations between menstrual product use and women’s health.FundingEuropean Research Council (EVOLPROOF, grant 648963)EthicsThe PAPCLEAR study ClinicalTrials.gov identifier is NCT02946346.Tweetable abstractA cross-sectional study finds a significant association between menstrual cup use and fungal infection risk.

The Covid-19 pandemic outbreak was followed by a huge amount of modelling studies in order to rapidly gain insights to implement the best public health policies. Most of these compartmental models involved ordinary differential equations (ODEs) systems. Such a formalism implicitly assumes that the time spent in each compartment does not depend on the time already spent in it, which is at odds with the clinical data. To overcome this “memoryless” issue, a widely used solution is to increase and chain the number of compartments of a unique reality (e.g. have infected individual move between several compartments). This allows for greater heterogeneity and thus be closer to the observed situation, but also tends to make the whole model more difficult to apprehend and parameterize. We develop a non-Markovian alternative formalism based on partial differential equations (PDEs) instead of ODEs, which, by construction, provides a memory structure for each compartment thereby allowing us to limit the number of compartments. We apply our model to the French 2021 SARS-CoV-2 epidemic and, while accounting for vaccine-induced and natural immunity, we analyse and determine the major components that contributed to the Covid-19 hospital admissions. The results indicate that the observed vaccination rate alone is not enough to control the epidemic, and a global sensitivity analysis highlights a huge uncertainty attributable to the age-structured contact matrix. Our study shows the flexibility and robustness of PDE formalism to capture national COVID-19 dynamics and opens perspectives to study medium or long-term scenarios involving immune waning or virus evolution.

SARS-CoV-2 variants raise major concerns regarding the control of COVID-19 epidemics. We analyse 40,000 specific RT-PCR tests performed on SARS-CoV-2-positive samples collected between Jan 26 and Feb 16, 2021. We find a high transmission advantage of variants and show that their spread in the country is more advanced than anticipated.

BackgroundCOVID-19 is spreading rapidly in nursing homes (NHs). It is urgent to evaluate the effect of infection prevention and control (IPC) measures to reduce COVID spreading.MethodsWe analysed COVID-19 outbreaks in 12 NH using rRT-PCR for SARS-CoV-2. We estimated secondary attack risks (SARs) and identified cofactors associated with the proportion of infected residents.ResultsThe SAR was below 5%, suggesting a high efficiency of IPC measures. Mask-wearing or establishment of COVID-19 zones for infected residents were associated with lower SAR.ConclusionsWearing masks and isolating potentially infected residents appear to limit SARS-CoV-2 spread in nursing homes.

ObjectivesMathematical models have unanimously predicted that a first-generation HIV vaccine would be useful and cost-effective to roll out, but that its overall impact would be insufficient to reverse the epidemic. Here, we explore what factors contribute most to limiting the impact of such a vaccine.MethodsRanging from a theoretical ideal to a more realistic regimen, mirroring the one used in the currently ongoing trial in South Africa (HVTN 702), we model a nested hierarchy of vaccine attributes such as speed of roll-out, efficacy, and retention of booster doses.ResultsThe predominant reasons leading to a substantial loss of vaccine impact on the HIV epidemic are the time required to scale up mass vaccination, limited durability and waning of efficacy.ConclusionsA partially effective HIV vaccine will be a critical milestone for the development of a highly effective, durable, and scalable next-generation vaccine. Accelerated development, expedited vaccine availability, and improved immunogenicity are the main attributes of a vaccine that could dramatically reverse the course of the epidemic in highly endemic countries.