New pandemic strains of influenza virus typically are more virulent than those that have been circulating longer, presumably because they present novel antigens to hosts. In this new study ...

Box 1. Current nomenclature for influenza viruses (WHO 1980). The formal nomenclature for the designation of influenza viruses was revised and published by the WHO [43]. The year of isolation ...

Bird flu appears to be rising in the U.S., but only among people exposed to infected animals — namely, cows and poultry.Since ...

TOKYO -- The H5N1 highly pathogenic avian flu virus may be more infectious to humans if passed on from cattle than directly from birds, a team of researchers in Japan has announced. The team led ...