Among the three latest outbreaks of highly pathogenic avian influenza (HPAI) in France, one has hit a duck flock that had been vaccinated.
All three of those affected flocks are in the northwestern region of Normandy.
Following a brief hiatus, the H5 virus was detected again in the department of Eure on December 23 at a farm with 25,000 birds. The N-group of the virus has not been determined, according to the official notification to the World Organisation for Animal Health (WOAH). A second outbreak was confirmed a few days later in 540 poultry in the adjacent department of Calvados.
Most recently confirmed is a third flock with just over 8,000 birds, bringing the total affected in this series so far to 34,120. Also located in Eure, the premises appears to be around 5km from the earlier outbreaks. According to the WOAH report, none of the poultry at the third farm showed symptoms or died, and close to 7,500 had been vaccinated.
France introduced mandatory HPAI vaccination of commercial duck flocks in October of 2023, and began a second round of vaccinations in the same month of last year.
Affected in the third outbreak were 7,500 ducks and 500 chickens, according to Ouest-France, all of which were humanely destroyed on December 31. It was the largest foie-gras farm in Normandy, and the ducks were reported to have been vaccinated against HPAI. Local authorities noted that vaccination helps to stop the further spread of the virus, but it does not prevent infection.
The source of infection at the first outbreak premises is uncertain, as the flock — 25,000 guinea fowl and chickens — had been housed since November 10. The same source reports an epidemiological link between the first two outbreaks, as the owner of the second farm had recently purchased poultry from the first. The 559 chickens, capons, and guinea fowl there were also euthanized on December 31.
Twice previously, the H5 virus was detected in vaccinated duck flocks in France. These involved premises in the adjacent region of Brittany during October of 2024.
Further HPAI outbreaks elsewhere in poultry flocks
Over the past 10 days, a number of national veterinary authorities in Europe have registered with WOAH new HPAI outbreaks involving the H5N1 HPAI virus serotype.
In Great Britain, infections have been confirmed at four more premises.
Two occurred in the eastern English county of Norfolk — involving laying hens and breeder ducks — and the others hit broiler breeders and pullets used for vaccine production further north in the East Riding of Yorkshire. These bring the country’s total outbreaks since the start of 2024 to 17, directly impacting close to 365,000 poultry.
Bringing Poland’s total outbreaks for the 12 months to the end of December to 50 were four additional outbreaks registered with WOAH. These involved three poultry farms in the northeastern province of Warmia-Masuria, and one in Silesia in the southeast.
According to the chief veterinary office, more than 3.2 million of the nation’s poultry were lost to HPAI last year.
Following a two-month hiatus, the same virus variant was confirmed in Portugal in the first days of 2025. Of the flock of 55,400 poultry at the farm in the Sintra district near Lisbon, 279 died and the rest have been destroyed.
The presence of the H5N1 HPAI virus has been detected for the first time in 12 months in the northeast Hungarian county of Szabolcs-Szatmar-Bereg, according to a WOAH notification. Affected were an unspecified number of meat ducks.
Meanwhile, Germany’s veterinary agency has confirmed to WOAH that the same virus variant has been detected in the southeastern state of Bavaria following a nine-month hiatus. At the farm, 300 of the 16,000 turkeys died, and the rest have been humanely destroyed.
Additional HPAI cases in captive, wild animals
HPAI outbreaks in captive birds have been recorded in three European states over the past 10 days.
Based on notifications to WOAH, these include one backyard flock near the Albanian capital Tirana, and a village flock in Kharkiv in eastern Ukraine. Six outbreaks in this category in Germany included backyard poultry in Mecklenburg-West Pomerania in the north-east, Rhineland-Palatinate in the west, and Bavaria. Also affected were zoos in Bavarian and Mecklenburg-West Pomerania.
Among their respective wild bird populations, eight European states have confirmed to WOAH that wild birds have recently tested positive for the H5N1 HPAI virus. These were Denmark, France, Germany, Hungary, the Netherlands, Poland, the Republic of Ireland, and the United Kingdom.
Meanwhile, first cases of HPAI caused by the H5N5 virus variant in “unusual species” have been detected in Iceland.
According to the WOAH notification, the death of three domestic cats in one household last month was attributed to this virus serotype. Source of infection is thought to be wild birds, several of which have tested positive for this variant since September of last year.
France reports first detection of influenza D virus in pig
For the first time, an influenza virus of the D “family” has been isolated from a pig in France.
Influenza D usually affects cattle, according to the French health agency, ANSES. However, it reported in December that the virus was detected in a pig from a farm in Brittany that raises both cattle and pigs.
Causing generally mild symptoms in swine, the D-virus has been detected in this species in several countries, including the United States, Italy, Luxembourg, the Netherlands, and the Republic of Ireland.
The finding suggests that the virus was transmitted from the cattle to the swine, as young cattle had developed respiratory disease soon after arriving at the farm, and the pig house ventilation inlet was in close proximity to the cattle barn.
According to ANSES, the risk of transmission of this virus to humans is very low. However, it recommends that the species should be separated, and each should have dedicated tools and equipment.
The H5N1 virus currently circulating across much of the world — mainly in birds — is an influenza A virus.
View our continuing coverage of the global avian influenza situation in poultry, and on disease developments in the U.S. dairy sector.
