H7N9 flu still better adapted to infect birds over humans

The protein structures of strains of the H7N9 virus (transmission electron micrograph shown) still appear to be better adapted to attaching to bird cells instead of human cells, suggesting that an immediate global pandemic is less likely than previously thought.

CDC

Even though the H7N9 bird flu killed 44 people in China in 2013, the virus still appears to be better adapted to infecting birds.

Researchers studied the structure of proteins from one strain of the H7N9 virus that caused the outbreak and tested how strongly one of the proteins bound to molecules on the surfaces of bird and human cells. The structure of the virus appears to be better adapted and to attach more strongly to the bird molecules compared with human molecules, the team reports December 6 in Science.

The results suggest that the current H7N9 virus does not yet have the needed mutations to cause an immediate global pandemic.

Ashley Yeager is the associate news editor at Science News. She has worked at The Scientist, the Simons Foundation, Duke University and the W.M. Keck Observatory, and was the web producer for Science News from 2013 to 2015. She has a bachelor’s degree in journalism from the University of Tennessee, Knoxville, and a master’s degree in science writing from MIT.