Le premier cas humain grave de grippe aviaire aux Etats-Unis est porteur d’un virus qui aurait muté à l’intérieur de son organisme pour s’adapter aux voies respiratoires humaines Capon, chickens, turkeys, geese and other Christmas cans are now part of the festive tables. Raised specifically between 140 and 170 days for a weight ranging from 2 kg (guinea fowl to more than 4 kg (capons), these poultry have an inimitable taste. Six months of free-range farming, 75 percent cereals mainly produced by the farmers themselves, a traditional finishing of dairy products allows the poultry of “Fermiers de Loue” to be served to one in 3 French people during holiday meals end of year. ( AFP / JEAN-FRANCOIS MONIER )
The first serious human case of avian flu in the United States carries a virus that may have mutated inside its body to adapt to human respiratory tract, American health authorities announced Thursday.
The American Centers for Disease Prevention and Control (CDC) announced on December 18 that an elderly patient was hospitalized in Louisiana in “critical condition” after being contaminated by the H5N1 virus.
A small portion of the virus found in this patient's throat showed genetic changes that could result in “increased binding of the virus” to certain “cellular receptors in the human upper respiratory tract,” the CDC revealed Thursday.
They were “probably generated during the replication of the virus in the patient”, indicated the CDC, specifying that no transmission of this mutated virus has been identified.
These changes have not been observed in contaminated birds, including those with which the patient may have been in contact in a farmyard.
Experts contacted by AFP said it was too early to determine whether these changes could allow the virus to spread more easily, or cause more serious cases in humans.
The mutation in question constitutes “a necessary step for a virus to become more contagious”, Angela Rasmussen, virologist at the University of Saskatchewan, in Canada, explained to AFP. “But I insist that it is not the only one” necessary, she added.
Rasmussen said the mutation could make it easier for the virus to enter cells, but further testing will need to be done in animals to confirm this.
Genetic modifications have already been observed in the past in seriously ill patients infected with avian flu, but have not yet resulted in an increase in the transmissibility of the virus to humans.
For Thijs Kuiken of the Erasmus University Medical Center in the Netherlands, these changes could lead to less serious infections, with the virus becoming “more likely” to “infect the upper respiratory tract”, causing runny nose or soreness. throat, affecting the lower respiratory tract, and causing pneumonia.
These observations therefore do not mean that we are getting closer to a “pandemic”, insisted Angela Rasmussen.
In addition to this Louisiana patient, 65 mild cases of the disease have been detected in humans in the United States since the start of the year, and others may have gone unnoticed, according to the CDC.
Avian influenza A (H5N1) first appeared in 1996, but since 2020 the number of outbreaks in birds has exploded and an increasing number of mammal species have been affected.
