Predicting the propagation of COVID-19 at an international scale: extension of an SIR model

International audienceObjectives Several epidemiological models have been published to forecast the spread of the COVID-19 pandemic, yet many of them have proven inaccurate for reasons that remain to be fully determined. We aimed to develop a novel model and implement it in a freely accessible web application.Design We built an SIR-type compartmental model with two additional compartments: D (deceased patients); L (individuals who will die but who will not infect anybody due to social or medical isolation) and integration of a time-dependent transmission rate and a periodical weekly component linked to the way in which cases and deaths are reported.Results The model was implemented in a web application (as of 2 June 2020). It was shown to be able to accurately capture the changes in the dynamics of the pandemic for 20 countries whatever the type of pandemic spread or containment measures: for instance, the model explains 97% of the variance of US data (daily cases) and predicts the number of deaths at a 2-week horizon with an error of 1%.Conclusions In early performance evaluation, our model showed a high level of accuracy between prediction and observed data. Such a tool might be used by the global community to follow the spread of the pandemic

Extension of a SIR model for modelling the propagation of Covid-19 in several countries.

Background Several epidemiologic models have been published to forecast the spread of the COVID-19 pandemic yet there are still uncertainties regarding their accuracy. We report the main features of the development of a novel freely accessible model intended to urgently help researchers and decision makers to predict the evolution of the pandemic in their country. Methods and findings We built a SIR-type compartmental model with additional compartments and features. We made the hypothesis that the number of contagious individuals in the population was negligible as compared to the population size. We introduced a compartment D corresponding to the deceased patients and a compartment L representing the group of individuals who will die but who will not infect anybody (due to social or medical isolation). Our model integrated a time-dependent transmission rate, whose variations can be thought to be related to the public measures taken by each country and a cosine function to incorporate a periodic weekly component linked to the way in which numbers of cases and deaths are counted and reported, which can change from day to day. The model was able to accurately capture the different changes in the dynamics of the pandemic for nine different countries whatever the type of pandemic spread or containment measures. The model provided very accurate forecasts in the relatively short term (10 days). Conclusions In early evaluation of the performance of our model, we found a high level of accuracy between prediction and observed data, regardless of the country. The model should be used by the community to help public health decisions as we will refine it over time and further investigate its performance

Reciprocal association between participation to a national election and the epidemic spread of COVID-19 in France: nationwide observational and dynamic modeling study.

Objective: To investigate possible reciprocal associations between the intensity of the COVID-19 epidemic in France and the level of participation at national elections. Design: Observational study and dynamic modelling using a sigmoidal mixed effects model. Setting: All hospitals where patients were admitted for COVID-19. Participants: All admitted patients from March 18, 2020 to April 17, 2020. Main outcome measures: Abstention and admission rate for COVID-19. Results: Mean abstention rate in 2020 among departments was 52.5%+/-6.4 and had increased by a mean of 18.8% as compared with the 2014 election. There was a high degree of similarity of abstention between the two elections among the departments (p<0.001). Among departments with a high outbreak intensity before the election, those with a higher participation were not affected by a significantly higher number of COVID-19 admissions after the elections. The sigmoidal model fitted the data from the different departments with a high degree of consistency. The covariate analysis showed that a significant association between participation and number of admitted patients was observed for both elections (2020: B=-5.36, p<1e-9 and 2014: B=-3.15, p<1e-6) contradicting a direct specific causation of the 2020 election. Participation was not associated with the position of the inflexion point suggesting no effect in the speed of spread. Conclusions: Our results suggest that the surrounding intensity of the COVID-19 epidemic in France did not have any local impact on citizens participation to a national election. The level of participation to the 2020 election had no impact on the spread of the pandemic

Repeated decrease of CD4+ T-cell counts in patients with rheumatoid arthritis over multiple cycles of rituximab treatment

International audienceSignificant peripheral blood CD4+ T-cell depletion has been observed after a first cycle of rituximab, a monoclonal antibody directed against the CD20 antigen, which is currently used in rheumatoid arthritis. Of note, an absence of CD4+ T-cell decrease has been observed in non-responders. Herein, we describe CD4+ T-cell changes over repeated cycles of rituximab and their relationship with clinical outcomes

The adherence questionnaires in chronic inflammatory rheumatic diseases and their psychometric properties: a systematic literature review

International audienc

There are 4 main questionnaires to assess adherence in inflammatory arthritis but none of them perform well: a systematic literature review.

International audienc

Recommandations pour l'évaluation et l'optimisation de l'adhésion aux traitements de fond médicamenteux des rhumatismes inflammatoires chroniques : un processus basé sur des revues de la littérature et un consensus d'experts

International audienc

Recommendations for the assessment and optimization of adherence to disease-modifying drugs in chronic inflammatory rheumatic diseases: A process based on literature reviews and expert consensus

International audienceBACKGROUND:Adherence to treatment is a key issue in chronic inflammatory rheumatic diseases (CIRDs).OBJECTIVE:To develop recommendations to facilitate in daily practice, the management of non-adherence to disease-modifying drugs in patients with rheumatoid arthritis, spondyloarthritis, psoriatic arthritis, connective tissue diseases or other CIRDs.METHODS:The process comprised (a) systematic literature reviews of methods (including questionnaires) to measure non-adherence, risk factors for non-adherence and efficacy of targeted interventions; (b) development of recommendations through consensus of 104 rheumatologist and nurse experts; (c) assessment of agreement and ease of applicability (1-5 where 5 is highest) by the 104 experts.RESULTS:(a) Overall, 274 publications were analysed. (b) The consensus process led to 5 overarching principles and 10 recommendations regarding adherence. Key points include that adherence should be assessed at each outpatient visit, at least using an open question; questionnaires and hydroxychloroquine blood level assessments may also be useful. Risk factors associated to non-adherence were listed. Patient information and education, and patient/physician shared decision, are key to optimize adherence. Other techniques such as formalized education sessions, motivational interviewing and cognitive behavioral therapy may be useful. All health professionals can get involved and e-health may be a support. (c) The agreement with the recommendations was high (range of means, 3.9-4.5) but ease of applicability was lower (2.7-4.4).CONCLUSIONS:Using an evidence-based approach followed by expert consensus, this initiative should improve the assessment and optimization of adherence in chronic inflammatory rheumatic disorders

L’édition en sciences humaines et sociales

En moins de vingt ans, l’édition en sciences humaines et sociales a été considérablement bouleversée. Tout a été réinventé : le marché du livre s’est transformé, le cadre légal a été radicalement modifié, la publication et la lecture en ligne ont connu un formidable essor, l’écriture même des sciences humaines s’est métamorphosée. Face à ces révolutions intellectuelles, techniques et socioéconomiques d’une ampleur inégalée, en faisant dialoguer éditeurs privés et publics, économistes, documentalistes, libraires, juristes, traducteurs, chercheurs, cet ouvrage collectif offre à celles et ceux qui se préoccupent du destin de l’édition en sciences humaines et sociales un premier bilan, à la fois clair et lucide, des changements survenus depuis le début du XXIe siècle