Avian flu: “It is a virus with very acute infections”, assures veterinary doctor Guillaume Le Loc’h

The avian influenza virus which kills black-headed gulls, is this a fairly unprecedented fact in your opinion in Toulouse?

No, this is the first time that this virus has been observed in the black-headed gulls of Toulouse. Now, that’s not surprising at all. There are indeed many cases affecting this species in Europe and France, particularly in the Paris region and the Lyon region. For the moment, we are not greatly impacted, because we have detected, it seems to me, five positive black-headed gulls. While in the Paris region, hundreds of seagulls died, even thousands. This is unprecedented in the sense that, in previous years, the black-headed gull was not necessarily the species most affected by avian flu.

Which species were most affected by the virus?

Rather the species of the family of ducks, geese, wild swans. The epizootic which started in 2021 and which continues to rage in Europe, has led to changes in the virus between some which previously were not very affected: black-headed gulls, gulls, northern gannets, in particular on Atlantic coasts where there was a huge mortality. The virus has also circulated in vulture species.

Do we have any idea how seagulls contract the virus?

No. It depends on the species. We have reservoir species (ducks, geese, swans) which can be the source of contamination, knowing that seagulls can live nearby. But the virus circulates in seagull populations, without contamination from other species.

Who is responsible in the department for examining infected black-headed gulls?

It is the French Office for Biodiversity which is generally responsible for verifying the abnormal mortality of wildlife. When this is the case, the analyzes are carried out in an approved laboratory. The virus triggers acute infections in seagulls which, once in contact, die within days.