Abstract Title
Serological survey of antibodies to avian influenza in the Norwegian cattle population
Abstract
The ongoing high pathogenic avian influenza (HPAI) H5N1 multistate outbreak affecting dairy cattle in the United States has highlighted the risks posed by HPAI viruses to domestic animal populations traditionally regarded as non-susceptible. As part of a One Health initiative, and to provide data for risk assessment of HPAI in cattle in Europe, we conducted a serological survey to determine the prevalence of antibodies to HPAI viruses in the Norwegian cattle population.
We used serum samples from the Norwegian Veterinary Institute Biobank. Samples were selected based on sampling time and location, including samples collected within a 25 km radius of a poultry outbreak or the centroid of a municipality with a wildlife case in 2022-2023, between 2 weeks and 6 months after the outbreak (n=535 individuals so far). Samples from 2019, prior to the first detection of HPAI virus in Norway, were used as baseline (n=827 individuals). Screening using the ID Screen Influenza A Antibody Competition Multi-species kit (ID vet), revealed a preliminary seroprevalence of influenza A antibodies of 1.2% in 2019 and 0.6% in 2022-2024. Hence, there was no increase in influenza A seroprevalence after HPAI emerged in Norwegian wild birds. Positive cattle sera will be further tested by haemagglutination inhibition test, using antigens representative of currently circulating H5 viruses, as well as human seasonal strains. So far our data show no evidence that avian influenza viruses have spread to Norwegian cattle, and establish a baseline for influenza A surveillance in this population.
We used serum samples from the Norwegian Veterinary Institute Biobank. Samples were selected based on sampling time and location, including samples collected within a 25 km radius of a poultry outbreak or the centroid of a municipality with a wildlife case in 2022-2023, between 2 weeks and 6 months after the outbreak (n=535 individuals so far). Samples from 2019, prior to the first detection of HPAI virus in Norway, were used as baseline (n=827 individuals). Screening using the ID Screen Influenza A Antibody Competition Multi-species kit (ID vet), revealed a preliminary seroprevalence of influenza A antibodies of 1.2% in 2019 and 0.6% in 2022-2024. Hence, there was no increase in influenza A seroprevalence after HPAI emerged in Norwegian wild birds. Positive cattle sera will be further tested by haemagglutination inhibition test, using antigens representative of currently circulating H5 viruses, as well as human seasonal strains. So far our data show no evidence that avian influenza viruses have spread to Norwegian cattle, and establish a baseline for influenza A surveillance in this population.
Co-Author(s)
Johanna Hol Fosse, Johan Åkerstedt, Kristin Udjus, Ida Kristin Myhrvold, Marie Myklatun Krossnes, and Ragnhild Tønnessen. Norwegian Veterinary Institute, NO-1433 Ås, Norway.
Abstract Category
Avian influenza in mammals, pandemic preparedness, and one health