Is Taihu Lake, Zhejiang Province the Geographic Source of the H7N9 Virus? (Map)

An important ahead-of-print article on the possible origins of the H7N9 virus has been published by researchers from the Zhejiang Provincial Center for Disease Control and Prevention in Hangzhou, China in the journal Zoonoses and Public Health. The researchers conducted genetic analyses of environment samples, human samples, and domestic and wild avian samples of the H7N9 virus from several provinces in the eastern portion of the People‘s Republic of China (PRC).

The article, entitled Hypothesis On The Source, Transmission and Characteristics of Infection of Avian Influenza A (H7N9) Virus – Based On Analysis of Field Epidemiological Investigation and Gene Sequence Analysis is behind a John Wiley & Sons paywall. However, within the freely available abstract, these Chinese researchers propose that the H7N9 virus now infecting people and domestic poultry originated with migratory bird populations in the Taihu Lake area of Zhejiang Province.

Their analysis suggests that . . . avian viruses carried by waterfowl combined with the virus carried by migratory birds, giving rise to avian influenza virus H7N9, which is highly pathogenic to humans. It is possible that the virus was transmitted by local wildfowl to domestic poultry and then to humans, or spread further by means of trading in wholesale poultry markets.

The authors speculate that . . . the infection source in the triangular area around Taihu Lake still remains. They also forecast that . . . The H7N9 epidemic will probably hit the area later in the year and next spring when the migratory birds return and may even spread to other areas.

This is a sobering forecast of future outbreaks of H7N9. Researchers from Zhejiang Province ought to know. More than 1/3 of all human H7N9 cases have been reported from Zhejiang Province.

Map