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 […]

The human immune system is made up of innate immunity and adaptive immunity. Innate immunity is not specific to invading pathogens, but allows an immediate response in the case of any aggression. The adaptive immune response is specifically directed against a pathogen, allowing immune-memory to take place, but has a slower reaction time. It is […]

The ability of viruses to mutate and evade the immune system’s attentions is a major obstacle to the development of universal vaccines, as well as to certain therapies. The mutations enabling evasion can change the “appearance” of viral surface proteins without altering their structure and functions, and so mask the virus to the eyes of […]

One of the first steps in the search for a vaccine consists of finding epitopes (or antigens, the region of the virus recognized by the immune system) that enable an efficient immune response to be triggered. The majority of studies dealing with SARS-CoV-2 have concentrated on the epitopes situated at the level of the spike […]

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 […]

Patients infected with SARS-CoV-2 may develop severe pneumonia, requiring respiratory support. Even though this condition affects only a minority of infected patients, it is the principal cause of death. Different clinical observations suggest that the inflammatory reaction caused by infection of the alveolar cells by SARS-CoV-2 may be different to that caused by other infectious […]

Over the last two decades, three coronaviruses have posed a danger to public health: SARS-CoV-1 in 2002-2003; MERS-CoV in 2012 and finally SARS- CoV- 2 in 2020. Coronaviruses are “enveloped” viruses, meaning that they are covered by an external phospholipid layer whose composition is close to the membranes of human cells. The spike (S) protein is threaded […]

The COVID-19 pandemic has caused the death of almost 2 million people across the world. In hospitals and research laboratories, knowledge about the illness has increased and certain treatments as well as vaccines have been developed. Autopsies have provided morphological information allowing us to see which organ failure has led to death. However, little molecular […]

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 […]

New variants of SARS-CoV-2 have been discovered recently, notably the VOC202020/01, known as the “English variant” and the 501Y.V2, known as the “South African variant”. Scientists are trying to understand why these variants seem to spread so quickly, and if the new vaccines will still give protection against them. The genomes of the 2 variants […]