New outbreaks of avian influenza in wild and domestic birds have been reported in Europe, it has emerged.
However, there continues to be no evidence of human-to-human spread of the disease.
These are the main findings of an avian influenza monitoring report, produced by the European Centre for Disease Prevention and Control (ECDC) and the EU reference laboratory (EURL).
It covers the period between September and December 2024.
Although the overall number of avian influenza cases remains low compared to previous years, the last quarter of the year saw an increase in cases in wild and domestic birds compared to the previous quarter, it says.
Most of the detections in both wild and domestic birds were found in South-Central Europe, mainly in areas with a high concentration of poultry farms.
Experts concluded that the large number of farms in these areas and the type of poultry production contributed to disease spread between farms.
A (H5N5) virus, a subtype of the avian influenza virus which causes mass mortality in wild birds, has significantly expanded its geographical and species range, spreading widely in different regions and wild bird species.
However, no new cases have been reported in mammals.
According to the ECDC, the risk of infection is currently low for the general public in Europe, and low to medium for people working with or exposed to infected animals or contaminated environments.
Outside of Europe, the US is seeing a “significant surge” in cases among cattle, with more than 800 establishments affected in 16 states.
Most of the cases are reported in California where the virus was also recently found in two batches of raw milk sold in retail shops. Additionally, A (H5N1) virus strain, which is different from the one affecting cattle, was detected for the first time in pigs in Oregon in a mixed livestock-poultry farm.
The report says this “is of concern” given the potential for pigs to be co-infected by different types of influenza viruses that could adapt and spread to other species.