(NEXSTAR) – The flu is spreading far and wide ... about 97% have turned up positive for influenza A. Influenza A is further divided into subtypes. You may have heard of H1N1 or H3N2 – those ...

told Salon H5N1 and other avian influenza viruses are a type A influenza virus. "We do need subtype confirmation to make sure it's ‘H5,’ and sub-type testing is not widely accessible." ...

A subtype of bird flu caused by avian influenza A (H5) virus has been spreading worldwide in wild birds with a few outbreaks in poultry, dairy cows and other mammals across the United States ...