The H5N1 avian flu continues to plague the world. Cases of contamination in mammals, particularly within a mink farm in Spain, have been identified.
- The bird flu virus is usually spread through contact with infected birds.
- At the end of January 2023, a swan tested positive for the H5N1 avian influenza virus in Gard.
Avian flu results in a viral disease that mainly affects wild and farmed birds. “While most avian viruses do not infect humans, some subtypes sometimes manage to cross the species barrier: this is the case of the H5N1 virus, pathogenic for humans and present in Asia”noted the Pasteur Institute. First detected in Hong Kong in 1997, the H5N1 avian flu virus reappeared at the end of 2003. It was responsible for epizootics in poultry in several Asian countries before contaminating the first humans.
Cases of H5N1 avian flu identified in a mink farm
Currently, the various global health authorities are dealing with an upsurge in H5N1 avian flu cases since October 2021. In the summer of 2022, France experienced the worst wave of the disease and had to slaughter around 20 million chickens, ducks and turkeys.
The spread of the virus accelerated again in December 2022, according to the Ministry of Agriculture. On December 20, 217 outbreaks of H5N1 avian flu were recorded on French farms, compared to 100 on December 2.
One of the fears of the health authorities is that the bird flu spreads on a large scale to mammals and humans. In October 2022, 50,000 visions were slaughtered in a farm in the province of Galicia (Spain) after the detection of cases.
In the same region, wild seabirds have been found sick or dead on the coast near the visions breeding farm. These vertebrates were positive for H5N1 avian influenza. In the eyes of the researchers, the minks were infected by contact with the contaminated birds. However, there is no evidence that the virus spread from mink to mink, as these mustelids are very susceptible to the bird flu virus.
H5N1 flu: clinical trials conducted to find a vaccine
“We observed a certain number of contaminations of mammals during the predation of sick birds: foxes, minks, bears or a cat in France. However, there are very few cases of contamination from mammal to mammal (…) Finally, there have been very rare human cases, difficult to document, and benign”said Jean-Luc Guérin, researcher at the National Veterinary School of Toulouse, to France News.
During his interview, the researcher was reassuring by explaining that the cases of human contamination are few, but that they are the subject of careful monitoring. “The phenomenon is taken seriously by the veterinary community, but there is no indication that the virus has changed radically and that it would pose a very significant risk to humans in the short term”he said.
To fight against this epizootic, the first clinical trials for a vaccine were conducted in duck farms in France. “These trials are being analyzed and, in parallel, there is work underway to put in place a real action plan to be able to implement vaccination from September 2023”, indicated Jean-Luc Guérin.
