Pandemic

The first case of COVID-19 was identified in December 2019 in Wuhan, China. By February 2020, the epidemic had spread and was detected in Europe, the Middle East, and in numerous other regions throughout the world. In the United States, the first case was identified retrospectively as having occurred a little earlier, in January 2020. […]

During the COVID-19 pandemic, priority has been given to prevention, detection, and responses to infection. While it is mainly adults who are at risk of dying from SARS-CoV-2, one aspect of the situation has tended to be neglected: the loss of parents or grand-parents, which can have severe consequences for children. Numerous studies, carried out […]

Following the trajectory of the pandemic and forecasting its evolution is of vital importance to plan public health measures. The key epidemiological parameters are estimated by using figures of case numbers, hospitalisations and deaths.qPCR tests, although generally interpreted as simply positive or negative, give a semi-quantitative result in the form of number of amplification cycles […]

Vaccinations are our main hope of ending this pandemic. However, that does not mean that we will be finished withnSARS-CoV-2. There will still be many unvaccinated people, either because supplies in their country are limited, or because they refuse vaccination. In addition, vaccines do not always prevent transmission of the virus, and the length of […]

By the 9 th of June 2021, COVID-19 had officially caused more than 3,7 million deaths across the globe. The United States and Brazil alone represent 28% of deaths worldwide and 59% of deaths across North and South America. In these 2 countries, the number of deaths varies between states, depending on which public health […]

After the 1st wave of infections in springtime 2020, Europe had to deal with an upsurge in the COVID-19 epidemic at the end of the summer. The number of new SARS-CoV-2 infections rose rapidly, causing a 2nd wave at the end of October. This wave led governments to once again impose drastic public health measures. […]

The COVID-19 pandemic has shown the kind of threat that infectious disease presents, and the necessity of scientific knowledge to understand, quantify and predict the risk that such pathologies pose. During the various waves of the epidemic, public health measures have been put in place, varying from country to country, and with different levels of […]

The most recent large-scale epidemics (flu, Zika, Ebola, COVID-19) have underlined the importance of developing models to predict the spread of illness. In particular, they help in the implementation of appropriate public health measures. The first such model, dating from 1927, focussed principally on population density. But in order to be effective, these models need […]

Airborne transmission is the main pathway for spreading infection in respiratory viruses such as SARS-CoV-2. Masks reduce contamination, both for infected people and those who risk infection. While type N95 or FFP2 masks only allow 5% of particles through, with surgical or similar masks the figure is between 30% and 70%. It is therefore understandable […]

Could the COVID-19 pandemic be the consequence of a laboratory leak in the virology institute in Wuhan? The question was raised soon after the start of the epidemic. Even though the majority of scientists affirm that SARS-CoV-2 was probably naturally transmitted from animals to humans, the possibility of a laboratory leak cannot be wholly excluded. […]