Abstract Title
H3N8 avian influenza viruses in poultry caused human infections in China
Abstract
Three human cases of avian influenza A (H3N8) virus infection have been reported in China since 2022. To investigate the origin and threat to humans posed by H3N8 viruses circulating in nature. We analyzed H3N8 viruses isolated from poultry between September 2021 and May 2022. A total of 98 H3N8 avian influenza viruses were isolated from 38,639 samples collected from 25 provinces in China; genetic analysis of 31 representative strains revealed 17 different genotypes. Ten genotypes isolated from live poultry markets derived their six internal genes from H9N2 viruses, and two of these genotypes were similar to the H3N8 viruses that caused human infections. The H3N8 viruses bound to both avian-type and human-type receptors and replicated efficiently in mice. Furthermore, some of them were highly transmissible among guinea pigs by respiratory droplets. The low pathogenicity of H3N8 viruses in poultry allows their continuous circulation with potential for reassortment. Therefore, careful monitoring of spill-over infections in humans is important to strengthen early-warning systems and maintain influenza pandemic preparedness.
Co-Author(s)
Jianzhong Shi1, Cheng Yan1, Congcong Wang1, Yuancheng Zhang1, Yaping Zhang1, Guohua Deng1, Hualan Chen1
1Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences
Abstract Category
Avian influenza in mammals, pandemic preparedness, and one health