URL

https://doi.org/10.1101/2020.09.07.20189779

Type d’article

Preprint

Thème

Infectiologie

Que retenir de cet article, en 1-2 phrases ?

The authors investigate the role of influenza in the transmission and lethality of SARS-CoV-2. They hypothesize that the 2 viruses may interact (based on previous evidence for other viruses) and that influenza may increase the transmission of SARS-CoV-2. They propose a new model (based on a classical SEIR model) and confront it to data in 4 European countries (Spain, Italy, Norway and Belgium).

Objectifs de l’étude / Questions abordées

Determining whether the influenza virus interacts with SARS-CoV-2 to increase its transmission and, potentially, its lethality. Several additional questions are also dealt with (potential spatial effects of SARS-CoV-2 transmission for instance).

Méthode

The authors built a stochastic model, based on a classical SEIR model, and estimated parameters by confronting the model to data. They used classical statistical analysis to conclude. They mainly compared the efficacy of several models (or modifications of the same model) to describe the data.

Résultats principaux

The authors show that influenza increases the transmission of SARS-CoV-2, based on data in Belgium, Italy, Spain and Norway. The other studies are not as conclusive. Influenza may have influenced SARS-CoV-2 lethality in Spain, but not in other countries for instance. Their model is able to correctly reproduce the main features of the SARS-CoV-2 epidemic, in agreement with previous publications on the same topic.

Commentaire/brève évaluation

The conclusions are in favor of fighting actively against the next influenza epidemic, as winter is coming and influenza will come back to Europe soon and could ease the transmission of SARS-CoV-2. Apart from its role in facilitating the propagation of SARS-CoV-2, the influenza virus does not appear to interact a lot with SARS-CoV-2 based on the analyses performed in this work. Some phenomena which are not taken into account could be interesting to consider for further work: age (which has a strong influence on influenza) and the fact that persons having both influenza and SARS-CoV-2 actually reduce their transmission due to influenza illness.