"I took great reassurance from this study," Alcabes added. "Very, very occasionally, you can get limited transmission of the avian virus from one infected human to another human, but it seems only to happen in families. There's nothing here to suggest new reasons to worry, let alone panic."
Added Dr. Pascal James Imperato, chairman of the department of preventive medicine and community health at SUNY Downstate Medical Center in New York City, "There's no proof positive that the father was not independently exposed to poultry."
The Pakistan case involved a poultry worker who became infected and survived last year, while three of his brothers were also infected, and two died, according to a BBC News report on Saturday.
Genetic-sequencing tests on bird flu virus samples collected from three of the four brothers confirmed human-to-human transmission of the H5N1 virus, the World Health Organization reported.
The northwestern region of Pakistan has 85 percent of the country's poultry farms and was one of the regions hardest hit by bird flu last year BBC News noted.
The World Health Organization has more on avian flu.
SOURCES: Anthony S. Fauci, M.D. director, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Md.; Philip Alcabes, Ph.D., epidemiologist, and associate professor, School of Health Sciences of Hunter College, New York City; Pascal James Imperato, M.D., distinguished service professor, and chair, department of preventive medicine and community health, SUNY Downstate Medical Center, New York City; April 8, 2008, online The Lancet
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