Literature update ViVa week 26-2026

1. Avian influenza reaches European dairy herds – silent spread in cattle demands integrated surveillance A farm-based investigation in the Netherlands screened milk and serum from 72 lactating cows and 38 youngstock after H5N1 clade 2.3.4.4b DI.2.1 infection was confirmed in a resident cat. No viral RNA was detected in 20 individual and bulk tank milk samples, but influenza A nucleoprotein ELISA and virus neutralization tests identified H5N1-specific antibodies in 34/72 cows (47.2%) and 24/38 youngstock (63.2%), with 20.0% of cows seropositive in milk. Haemagglutination inhibition titers were low, and infection appeared largely subclinical. Findings indicate expansion of the mammalian host range of Eurasian H5N1 and highlight serum as a more sensitive matrix for serosurveillance in cattle. Comment and opinion: This first serological evidence of H5N1 infection in European dairy cattle is not unexpected and I suppose local veterinary and public health planning is ready for implementation: Targeted cattle surveillance, strict raw...