CHINA> Backgrounder
Apart from H5N1, have other avian influenza viruses ever infected humans?
(WHO)
Updated: 2004-02-02 16:09
Yes. Two other avian strains have caused illness in humans, but the outbreaks were not as severe as those caused by the H5N1 strain.

The H9N2 strain, which is not highly pathogenic in birds, caused mild cases of illness in two children in Hong Kong in 1999 and in one child in mid-December 2003, also in Hong Kong.

An outbreak of highly pathogenic H7N7 avian influenza in birds, which began in the Netherlands in February 2003, caused the death of one veterinarian (from acute respiratory distress syndrome) two months later, and mild illness in 83 poultry workers and members of their families.