Cows have the same receptors for flu viruses as humans and birds, raising concerns that cows could be mixing bowls – hosts that help the virus learn to better spread between people. This finding is particularly alarming given the recent outbreak of H5N1, or highly pathogenic avian influenza, in dairy cows.
H5N1 Spreading to Mammals
H5N1 has been primarily confined to the bird population for years, but it has recently begun to infect a growing number of mammals, suggesting that the virus might be adapting and moving closer to becoming a human pathogen. The discovery of H5N1 in dairy cows is particularly concerning because cows have both human and bird sialic acid receptors in their respiratory tracts, making them potential hosts for both human and bird flus.