Characterisation of an Avian Influenza A Virus Isolated from a Human--is an Intermediate Host Necessary for the Emergence of Pandemic Influenza Viruses?

The partial sequencing of the internal and the neuraminidase genes of isolate 268/96 obtained from a woman with conjunctivitis showed all seven to have closest homology with avian influenza viruses. The entire nucleotide sequence of the haemagglutinin gene of 268/96 had close, 98.2%, homology with an H7N7 virus isolated from turkeys in Ireland in 1995. This appears to be the first reported case of isolation of an influenza A virus from a human being infected as a result of direct natural transmission of an avian influenza virus from birds.