Influenza A (H7N9) viewed through an electron microscope.WIKIPEDIA, CYNTHIA S. GOLDSMITH AND THOMAS ROWEA group of 22 prominent influenza researchers have today (August 7) published a letter in both Nature and Science, stressing the need for a new wave of controversial studies on the H7N9 bird flu virus—so-called “gain-of-function” experiments that deliberately engineer mutant viruses to identify mutations that would make naturally occurring strains more transmissible or virulent in mammals.
This subtype of flu had no history of infecting humans until three cases were reported in China this March. Since then, H7N9 has infected at least 133 people and killed 43. Warmer summer weather and the recent closure of the country’s live bird markets have helped to contain the outbreak, but as colder months approach, researchers fear that the virus could re-emerge.
Last year, gain-of-function experiments on the H5N1 virus from two groups—led by Ron Fouchier from the Erasmus Medical Center and Yoshihiro Kawaoka from the University of Wisconsin-Madison—ignited a fierce ethical debate. Both had created mutant viruses that could spread through the air between ferrets, and identified handfuls of mutations that enhanced transmissibility. Those experiments led to months of discussion about whether the results ...
