We are grateful to the sampling staff of Nanchang Center for Disease Control and Prevention for their contributions to field work and sample collection. The American Society of Tropical Medicine and Hygiene has waived the Open Access fee for this article due to the ongoing COVID-19 pandemic.
Tan KX, Jacob SA, Chan KG, Lee LH, 2015. An overview of the characteristics of the novel avian influenza A H7N9 virus in humans. Front Microbiol 6: 140.
Le TH, Nguyen NT, 2014. Evolutionary dynamics of highly pathogenic avian influenza A/H5N1 HA clades and vaccine implementation in Vietnam. Clin Exp Vaccine Res 3: 117–127.
Yin X, Deng G, Zeng X, Cui P, Hou Y, Liu Y, Fang J, Pan S, Wang D, Chen X, 2021. Genetic and biological properties of H7N9 avian influenza viruses detected after application of the H7N9 poultry vaccine in China. PLoS Pathog 17: e1009561.
WHO, 2021 Monthly Risk Assessment Summary. Geneva, Switzerland: World Health Organization. Available at: https://www.who.int/influenza/human_animal_interface/HAI_Risk_Assessment/en/.
Takekawa JY, Newman SH, Xiao X, Prosser DJ, Spragens KA, Palm EC, Yan B, Li T, Lei F, Zhao D, 2010. Migration of waterfowl in the East Asian flyway and spatial relationship to HPAI H5N1 outbreaks. Avian Dis 54: 466–476.
Cappelle J, Zhao D, Gilbert M, Nelson MI, Newman SH, Takekawa JY, Gaidet N, Prosser DJ, Liu Y, Li P, 2014. Risks of avian influenza transmission in areas of intensive free-ranging duck production with wild waterfowl. EcoHealth 11: 109–119.
Yuan J, Lau EH, Li K, Leung YH, Yang Z, Xie C, Liu Y, Liu Y, Ma X, Liu J, 2015. Effect of live poultry market closure on avian influenza A(H7N9) virus activity in Guangzhou, China, 2014. Emerg Infect Dis 21: 1784–1793.
Chen J, Xu Z, Hu W, Lu J, 2020. Live poultry market closure and avian influenza A (H7N9) infection in cities of China, 2013–2017: an ecological study. BMC Infect Dis 20: 369.
Wu Y, Gao GF, 2013. Lessons learnt from the human infections of avian-origin influenza A H7N9 virus: live free markets and human health. Sci China Life Sci 56: 493–494.
Yu H, Wu JT, Cowling BJ, Liao Q, Fang VJ, Zhou S, Wu P, Zhou H, Lau EH, Guo D, 2014. Effect of closure of live poultry markets on poultry-to-person transmission of avian influenza A H7N9 virus: an ecological study. Lancet 383: 541–548.
Liu S, Zhuang Q, Wang S, Jiang W, Jin J, Peng C, Hou G, Li J, Yu J, Yu X, 2020. Control of avian influenza in China: strategies and lessons. Transbound Emerg Dis 67: 1463–1471.
Wang Q, Cheng W, Yu Z, Ling F, Mao H, Chen E, 2017. Risk factors for avian influenza virus contamination of live poultry markets in Zhejiang, China during the 2015–2016 human influenza season. Sci Rep 7: 42722.
Tang X, Yang Z, Wang M, Zheng B, 2014. Enhanced disinfection and regular closure of wet markets reduced the risk of avian influenza A virus transmission. Clin Infect Dis 58: 1037–1038.
He F, Chen EF, Li FD, Wang XY, Wang XX, Lin JF, 2015. Human infection and environmental contamination with Avian influenza A (H7N9) virus in Zhejiang province, China: risk trend across the three waves of infection. BMC Public Health 15: 931.
Liu B, Havers F, Chen E, Yuan Z, Yuan H, Ou J, Shang M, Kang K, Liao K, Liu F, 2014. Risk factors for influenza A(H7N9) disease—China, 2013. Clin Infect Dis 59: 787–794.
Quan C, Wang Q, Zhang J, Zhao M, Dai Q, Huang T, Zhang Z, Mao S, Nie Y, Liu J, 2019. Avian influenza A viruses among occupationally exposed populations, China, 2014–2016. Emerg Infect Dis 25: 2215–2225.
Bi Y, Li J, Li S, Fu G, Jin T, Zhang C, Yang Y, Ma Z, Tian W, Li J, 2020. Dominant subtype switch in avian influenza viruses during 2016–2019 in China. Nat Commun 11: 5909.