NIH-supported researchers examine genetics of H7N9 influenza
The National Institutes of Health-supported research was published online in Eurosurveillance. The research provided clues to the origin of the virus, its transmissibility to humans and possible sensitivity to existing influenza treatments. The Centers of Excellence for Influenza Research and Surveillance program of the National Institute of Allergy and Infectious Diseases and multiple Japanese organizations funded the research.
"The H7N9 influenza virus is a new concern that the public health and scientific communities will continue to track closely, including watching for any genetic mutations that might enable the virus to become transmissible from person to person or to cause more severe disease," Anthony Fauci, the director of the NIAID, said. "Having rapid access to the viral genetic information is essential to understanding how the virus is evolving and ultimately to developing a candidate vaccine, if warranted."
Masato Tashiro, a scientist with the National Institute of Infectious Diseases in Japan, and Yoshihiro Kawaoka, a scientist with the University of Wisconsin-Madison and the University of Tokyo, found that the virus causes mild disease in birds but has mutated to more efficiently cause disease in humans. The researchers also determined the four sequences of the virus will not be treatable with ion channel inhibitors, a major class of anti-influenza drugs.
The researchers did find, however, that three of the four H7N9 viruses are likely to be treatable with NA inhibitors, another class of anti-influenza drugs that includes zanamivir (Relenza) and oseltamivir (Tamiflu).