Pandemic

The coronavirus epidemics derive from animals, but human  to animal transmission is poorly understood. A recent study carried out on mink on a Dutch farm (see the News-COVID-19.info 16-22 November newsletter) showed that these animals had been infected by men with SARS-CoV-2, and that other humans had later been reinfected by the mink (a process […]

Measures taken to fight the virus are many and varied. In addition to mask-wearing and social-distancing, several countries have put quarantine measures in place. In France the length of quarantine has been changed from 14 to 7 days because of socio-economic repercussions that the longer period engenders, so the study of the impact of quarantine […]

Africa represents 17% of the world’s population. Paradoxically, it represents only 5% of COVID-19 cases and 3% of worldwide deaths in July 2020. These figures are well below those in other countries (China, Europe, USA), where seroprevalence (the presence of anti- SARS-CoV-2 antibodies in the blood) was generally between 5 and 11% at the end […]

Individuals infected by SARS-CoV-2 can transmit the virus whether they are pre-symptomatic (the period prior to the beginning of symptoms), symptomatic or asymptomatic. After becoming infected, an individual undergoes a period of incubation during which time the viral charge is too small to be detected. This is followed by a phase of exponential multiplication of […]

The purpose of virus detection is to identify and isolate COVID-19 patients so as to limit transmission and control the outbreak. But positive cases have been largely under-estimated since many of them are asymptomatic or cause only slight symptoms, and so are not counted. At the beginning of the epidemic, because nothing like this had […]

The most widespread current test for SARS-CoV-2 is the PCR test, which detects the virus’ presence by amplifying its genetic material. Although it is used worldwide, results may often only arrive several days after testing due to laboratories being saturated. There is therefore clearly an urgent need for quicker tests that are just as reliable. […]

The SARS-CoV-2 virus had its origin in animals, from where it was transmitted to humans, and this quickly led to the pandemic. The transmission of the virus is principally human-to-human, but it may be transmitted to certain animals, particularly domestic ones. Sporadic cases of dogs and cats being infected have been reported: some dogs have […]

Infection by SARS-CoV-2 does not seem to confer herd-immunity when the virus spreads to large cities. Brazil is one of the countries worst affected by COVID-19 today. Manaus, the capital and largest metropolis of the Amazonian region with more than 2 million inhabitants and a population density of 158 inhabitants / km2, is one of […]

Although we know that the clinical severity of infection by SARS-CoV-2 increases with age, little information exists concerning the virus’ mode of transmission. Having a better understanding of the factors which may contribute to transmission is very important if we want to minimize the impact of the pandemic on our social life. To this end, […]

Many governments have seen a possible way out of the coronavirus crisis in digital technologies: anti-COVID test and trace applications that use Bluetooth… But there is an inherent dilemma linked to the use of these systems: on the one hand, they need maximum participation in order to be effective; on the other hand, this effectiveness […]