Avian influenza or bird flu outbreaks occurred less frequently in poultry birds in March and April this year compared to the previous reporting period - December 3, 2022 to March 1, 2023 - and also when the data was set against the documentation from spring 2022.
Those findings were revealed in a report on avian influenza by the European Food Safety Authority (EFSA), the European Centre for Disease Prevention and Control (ECDC), and the EU reference laboratory (EURL).
Bird flu outbreaks were reported in Hungary (60), Italy (10), Germany (6), the UK (4), Czechia (3), Denmark (2), France (2), Poland (2), Bulgaria (1), Sweden (1), and Switzerland (1). The majority of those cases were classified as primary outbreaks without secondary spread and some of them were associated with atypical disease presentation, in particular low mortality, noted the agencies.
The detection of cases in wild birds in March and April decreased compared to the previous reporting period but increased compared to spring last year.
HPAI has continued to expand in the Americas and is expected to reach the Antarctic soon, reads the report.
Infections were detected in six new mammal species for the first time, including in marine mammals. Two cases were also reported in cats in the US and one case in a dog in Canada. As a precautionary measure, EFSA said it recommends preventing pets from being exposed to dead or diseased animals in areas affected by HPAI.
Records broken
In Europe, over 2 467 outbreaks were detected in poultry in 2021-2022, which saw 48 million domestic birds culled in 37 countries. It was the largest bird flu epidemic so far recorded on the continent. Over 2 million birds were destroyed in Germany alone in 2021.
Case study: France
Two primary poultry outbreaks were reported in France during this reporting period, and both occurred in commercial farms rearing turkeys and broilers, noted the report.
In the broiler farms, the birds had outdoor access, with increased mortality and the presence of clinical signs reported. The turkey operations also reported higher mortality levels, the presence of clinical signs as well as drop in feed and water intake. "No data on the number of exposed people or the source of introduction were available at the time of publication of this report.”
The authors suggested that the decrease in the overall number of poultry outbreaks and the huge reduction in the secondary spread of virus infections seen in France might be the consequence of a voluntary reduction in the density of operations involved in domestic duck production in the southwestern part of the country.
Vaccination
‘The fight against avian influenza is at the top of our priorities,’ EU health commissioner, Stella Kyriakides, said in February this year when announcing new EU rules on the vaccination of animals to curb the spread of the disease. ‘These outbreaks are causing enormous damage to this agricultural sector and hamper trade.’
For the moment, just one vaccine is authorised in the EU against bird flu. The new EU rules, which will entered into force in March, will allow the movement of animals and goods from businesses and zones where vaccination has taken place, according to the official EU research and innovation magazine, Horizon.