Monthly overview bird flu 2025

In the month of January, many wild birds were found dead, of which 122 were sent by the DWHC to the WBVR to be tested for avian influenza. These were mainly Barnacle Geese, but throughout the month, more and more gulls and birds of prey were also reported. Other, less common bird species that tested positive for avian influenza this month included the Eurasian Curlew, Grey Heron, and the Common Kestrel.

A fox found in Hoofddorp, municipality North-Holland, was also found to be positive for infection with bird flu.

In January, avian influenza was also detected in kept animals, such as the poultry farm in the province of Friesland where about 25,000 animals had to be culled.

Distribution map of reports of dead wild birds in the Netherlands

The DWHC, together with Sovon, Waarneming.nl, and the Bird Flu App, monitors where dead wild birds have been found in the Netherlands. The focus is mainly on bird species at risk for avian influenza, but other bird species are also included. The map below provides a national overview of bird mortality in January.

In the month of February, the trend of reports was similar to the previous month. A total of 128 birds were sent by the DWHC to the WBVR for avian influenza testing. Once again, the largest numbers of reported and examined birds were barnacle geese. In addition, increasing numbers of gulls and birds of prey were reported. This month, the less commonly affected bids species that tested positive for infection with the virus included the Eurasian Curlew, common Kestrel, Western Barn Owl, Short-eared Owl, common Eider, Red Knot, and for the first time in 2025: the Ruddy Turnstone.

This month, a fox found in Doorn, province Utrecht, tested positive for bird flu.

Among kept animals, avian influenza was found at a laying hen farm in the province of Friesland, where about 37,000 animals had to be culled, and among the birds at a petting zoo in the province of North Brabant, where 47 birds were culled.

Distribution map of reports of dead wild birds in the Netherlands

The DWHC, together with Sovon, Waarneming.nl, and the Bird Flu App, monitors where dead wild birds have been found in the Netherlands. The focus is mainly on bird species at risk for avian influenza, but other bird species are also included. The map below provides a national overview of bird mortality in February.

In the month of March, a total of 75 birds were sent by the DWHC to the WBVR for avian influenza testing. The number of birds reported to the DWHC as suspected cases of bird flu decreased compared to the previous month. Again, the virus was most frequently found in geese this month. Additionally, increasing numbers of gull species and swans were reported. This month, the less commonly affected bird species that tested positive for the virus was the Sanderling.

Also, this month a fox in De Fryske Marren, province Friesland, tested positive for bird flu.

Among kept animals, the avian influenza virus was detected at a turkey farm in Putten, province Gelderland, where approximately 27,000 animals had to be culled.

Distribution map of reports of dead wild birds in the Netherlands

The DWHC, together with Sovon, Waarneming.nl, and the Bird Flu App, monitors where dead wild birds have been found in the Netherlands. The focus is mainly on bird species at risk for avian influenza, but other bird species are also included. The map below provides a national overview of bird mortality in March.

In the month of April, a total of 39 birds were sent to the WBVR by the DWHC for avian influenza testing. The number of reported birds suspected of avian influenza decreased compared to the previous month. This month, the avian influenza virus has been found in five birds. All five birds were mute swans collected on the same day on the same location in the municipality of Leeuwarden, province Friesland. Other birds from the province of Friesland tested negative for bird flu.

Additionally, no mammals have tested positive for bird flu in April, and no outbreaks have been reported among kept animals.