This finding is significant because, while the spring migration is definitely a higher risk transmission period for poultry, it highlights the possibility of the virus infecting other animals on farms with multiple species.
Mixed Species Farming
Before March 2024 there were no reports about H5N1 infections in goats or hoofed livestock in general outside of laboratory experiments. In addition to the first documented cases of H5N1 in goats, H5N1 in cows has been documented for the first time as well. Goats have so far been considered a minor risk from a public health perspective. However, mixed species farming could lead to transmission from birds to mammals and back to birds. Another case involving poultry, dogs, and a cat was documented on a mixed species farm in Brescia, Italy.
USDA’s National Veterinary Services Laboratories confirmed highly pathogenic avian influenza (HPAI) in neonatal goat kids that demonstrated neurologic signs from a Minnesota backyard premises recently affected with HPAI. The goats on the premises shared the same pasture and sole water source with infected ducks and chickens. The goats began to kid only days after the birds were depopulated. Of 10 goat kids that have died, ranging from 5 days to 9 days of age, five goat kids between 7 and 9 days of age have tested positive on brain and other tissues for H5N1 clade 2.3.4.4b virus. Whole genome sequence data available to date from the chickens, ducks, and the first goat kid tested share high identity, and are Eurasian/North American reassortant genotype B3.6
The goats were tested after the farmer noticed unusual deaths in newborn goats, which followed culling of poultry as part of the response to the February outbreak. The goats and the poultry shared the same space, as well as the same water source.