No indications of avian influenza on other dairy farms in the Netherlands

In January 2026, antibodies against avian influenza were detected in a Dutch cow in the province of Friesland. This prompted more extensive investigations at this specific dairy farm as well as at other dairy farms. Together with the Royal GD, Wageningen Bioveterinary Research (WBVR) carried out retrospective research into the presence of avian influenza virus and antibodies against the virus in cattle. To do so, archived bulk milk samples from the Friesian farm were analysed and the farm was monitored over an extended period. In addition, WBVR examined more than 3000 previously collected blood samples from cattle on other dairy farms in the Netherlands to identify any potential past infections with avian influenza.

No avian influenza virus was detected in the bulk or individual milk samples from the Friesian farm collected between November 2025 and January 2026. However, antibodies against the avian influenza virus were found in 47% of the lactating cows and in 63% of the young stock.

No antibodies against highly pathogenic avian influenza (HPAI) were detected in the more than 3000 blood samples originating from other Dutch dairy farms.

The WBVR findings were discussed in the Zoonoses Response Team (RT-Z) meeting, a panel of experts from various Dutch institutes. According to the RT-Z experts, the case in Friesland appears to have been an isolated incident, and it is likely that avian influenza infections in cattle occur only very rarely.

Although the studies carried out suggest that the risk of infection in cattle is low, the detection of antibodies in several cows on the single farm in Friesland underlines the importance of vigilance among dairy farmers. “Avian influenza is a notifiable disease and, although the current number of avian influenza cases in cows is limited to a single farm, continued vigilance remains essential,” emphasises Matthijn de Boer, Head of Statutory Research Tasks at WBVR.