Interspecies transmission of canine influenza virus H5N2 to cats and chickens by close contact with experimentally infected dogs.

The novel H5N2 influenza virus, CA/SD/JT01/09, was isolated from the dog exhibiting respiratory signs in China in 2009. Dog to dog transmission of the novel H5N2 was previously confirmed. But interspecies transmission of the virus between dogs and the other animals has still remained unclear. To determine whether the virus can be transmitted directly from dogs to cats and chickens, we conducted contact exposure experiments. Susceptible cats and chickens were housed in the room which the novel H5N2 infected dogs were housed in, respectively. As a result, only one cat showed clear manifestations of H5N2 infection, but susceptibility of the other cats to H5N2 was confirmed by seroconversion. Eight of the exposure chickens showed clear manifestations of illness and 2 chickens died, and it demonstrates that chickens are susceptible to the recombinant H5N2. It implied that close contact between the H5N2-infected dogs and the cats and chickens resulted in spread of the virus to the sentinel animals.