HKU researchers identify mutation in H7N9 that enhances human infection
Investigators from The University of Hong Kong (HKU) recently identified a mutation in H7N9 virus which causes the virus to possess a higher ability to infect humans while maintaining its ability to circulate effectively in poultry.
Genetic analysis revealed that the NS segment of the H7N9 virus contains a G540A substitution mutation located in the exonic splicing enhancer motif in the mRNA of influenza A viruses. The G540A mutation allows virus replication in mammalian cells while retaining replication ability in avian cells. [Nat Commun 2017, doi:10.1038/ncomms14751]
“This mutation may provide an important biomarker for monitoring transmission of avian influenza viruses in humans and preventing human-to-human transmission of the viruses. The mutation can also serve as a novel target of anti-influenza drug development,” said Professor Honglin Chen of the State Key Laboratory for Emerging Infectious Diseases and Department of Microbiology, HKU.
The outbreak of H7N9 avian influenza was first detected in Eastern China in 2013. As of February 2017, 1,258 H7N9 cases have been confirmed with a 41 percent death rate. [MMWR Morb Mortal Wkly Rep 2017;66:254-255]