Raw milk is risky, but airborne transmission of H5N1 from cow's milk is inefficient in mammals

While H5N1 avian influenza virus taken from infected cow's milk makes mice and ferrets sick when dripped into their noses, airborne transmission of the virus between ferrets -- a common model for human transmission -- appears to be limited. These and other new findings about the strain of H5N1 circulating among North American dairy cattle this year come from a set of laboratory experiments. Together, they suggest that exposure to raw milk infected with the currently circulating virus poses a real risk of infecting humans, but that the virus may not spread very far or quickly to others.