Isolation of avian influenza viruses in central Oklahoma

Aquatic birds are the natural hosts for influenza virus. It is established that avian influenza viruses provide the gene pool for the generation of new strains of human influenza virus, which can cause pandemic infections. The recent outbreak of an avian influenza virus (H5N1) in Hong Kong not only produced high mortality in chickens, but also resulted in six human fatalities. This outbreak indicates that avian influenza virus can be pathogenic for humans. We surveyed local waterfowl habitats by taking water and fecal samples for virus isolation and identification. We isolated avian influenza viruses from ponds and small lakes in Bartlesville, Lawton, Stillwater, and Tulsa. The density of birds in these sites is small. However, our virus isolation rate is comparable to that found in higher density habitats. The risk of human infection remains to be determined. We encourage primary care physicians to submit samples for virus surveillance.