[H5N1 influenza : is a pandemic imminent ?].

A totally unprecedented panzootic of the H5N1 influenza virus has been sweeping the avian world since 2020. The potential danger of the virus was first measured when it infected humans in South-East Asia, sporadically for almost 30 years. More recently, mink farms, marine mammals and dairy cows have been affected by the virus and appear to have infected each other, raising the level of concern about the risk to humans. All measures must therefore be taken in the herds concerned to reduce replication of the virus and the risk of mutations that could one day allow human-to-human transmission. However, the highly hypothetical H5N1 pandemic threat needs to be put into perspective by comparison with other, more certain threats, in particular those posed by the H1N1, H2N2 and H3N2 influenza viruses, which are already known to be adapted to humans.