Human infections with the emerging avian influenza A H7N9 virus from wet market poultry: clinical analysis and characterisation of viral genome

• Published in: The Lancet (British edition) 2012-09, Vol.381 (9881), p.1916-1925
• Main Authors: Chen, Yu, Liang, Weifeng, Yang, Shigui, Wu, Nanping, Gao, Hainv, Sheng, Jifang, Yao, Hangping, Wo, Jianer, Fang, Qiang, Cui, Dawei, Li, Yongcheng, Yao, Xing, Zhang, Yuntao, Wu, Haibo, Zheng, Shufa, Diao, Hongyan, Xia, Shichang, Zhang, Yanjun, Chan, Kwok-Hung, Tsoi, Hoi-Wah, Teng, Jade Lee-Lee, Song, Wenjun, Wang, Pui, Lau, Siu-Ying, Zheng, Min, Chan, Jasper Fuk-Woo, To, Kelvin Kai-Wang, Chen, Honglin, Li, Lanjuan, Yuen, Kwok-Yung
• Format: Article
• Language: English
• ISSN: 0140-6736

Human infection with avian influenza A H7N9 virus emerged in eastern China in February, 2013, and has been associated with exposure to poultry. We report the clinical and microbiological features of patients infected with influenza A H7N9 virus and compare genomic features of the human virus with those of the virus in market poultry in Zhejiang, China. Methods: Between March 7 and April 8, 2013, we included hospital inpatients if they had new-onset respiratory symptoms, unexplained radiographic infiltrate, and laboratory-confirmed H7N9 virus infection. We recorded histories and results of haematological, biochemical, radiological, and microbiological investigations. We took throat and sputum samples, used RT-PCR to detect M, H7, and N9 genes, and cultured samples in Madin-Darby canine kidney cells. We tested for co-infections and monitored serum concentrations of six cytokines and chemokines. We collected cloacal swabs from 86 birds from epidemiologically linked wet markets and inoculated embryonated chicken eggs with the samples. We identified and subtyped isolates by RT-PCR sequencing. RNA extraction, complementary DNA synthesis, and PCR sequencing were done for one human and one chicken isolate. We characterised and phylogenetically analysed the eight gene segments of the viruses in the patient's and the chicken's isolates, and constructed phylogenetic trees of H, N, PB2, and NS genes.