The recent canine influenza outbreak in Chicago is caused by a different strain of the virus than was earlier assumed. According to laboratory scientists at Cornell University and the University of Wisconsin, the outbreak is caused by a virus related to Asian strains of influenza A H3N2 viruses—not the H3N8 strain. Both strains can cause high fever, loss of appetite, coughing, nasal discharge, and lethargy. Symptoms may be more severe with the H3N2 virus. H3N2 has also caused infection and respiratory illness in cats.