The US, like other countries that raise poultry, is facing the worst avian influenza outbreak ever recorded. The disease, widely known as avian influenza, and HPAI or H5N1, has killed over 58 million birds have died in the US due to this outbreak, including 804,734 in California alone. At least 43 million of the 58 million birds were culled in efforts to slow the spread of the disease. The outbreak started in January 2022 and has spread across flocks in 46 states during the past year.
Unlike the outbreak that occurred in 2014, this disease is spread from wild birds and other mammals, not solely from farm to farm transmission. The disease is transferred through saliva and bodily fluids. Other animals in the US, such as ducks, eagles, bears, foxes, raccoons, possums, mountain lions, bobcats, and even a bottlenose dolphin, have also trasnferred the disease.
The particular strain of influenza virus under discussion does not seem to have as severe an impact on broilers (chickens bred for meat production) as it does on layers (hens that produce table eggs) and turkeys. According to Amy Hagerman, an assistant professor of agricultural economics at Oklahoma State University, for some reason, turkeys and layer birds tend to be more susceptible to the virus.
Based on data from Statista in 2022, there were more than 379 million layer chicken in the United States.
Farmers and local authorities typically bury the culled birds in order to reduce the spread of the disease. According to CNN Business, H5N1 has hit Japan so hard, that they are running out of land to bury the culled birds.
According to Amy Hagerman, an expert in agricultural economics at Oklahoma State University, influenza typically dissipates when the weather becomes hot. This was evident during the 2014-2015 outbreak when Hagerman worked at the U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS). The hot summer weather contributed to the virus being killed off in the environment, effectively ending the outbreak. However, during the recent outbreak, the virus persisted through the summer months, and there was no significant reduction in its circulation within the wild bird population.
“Instead, the virus remained dormant and resurged during the cooler and wetter months of the fall” said Hagerman.
This prolonged outbreak is concerning to Hagerman, who points out that Europe has been experiencing two years of HPAI (highly pathogenic avian influenza) outbreaks.
