title: Epidemiological and clinical characteristics and risk factors for death of patients with avian influenza A H7N9 virus infection from Jiangsu Province, Eastern China.
abstract: BACKGROUND
  A novel avian influenza A (H7N9) virus has caused great morbidity as well as mortality since its emergence in Eastern China in February 2013. However, the possible risk factors for death are not yet fully known.
  
  
  RESULTS
  Patients with H7N9 virus infection between March 1 and August 14, 2013 in Jiangsu province were enrolled. Data were collected with a standard form. Mean or percentage was used to describe the features, and Fisher's exact test or t-test test was used to compare the differences between fatal and nonfatal cases with H7N9 virus infection. A total of 28 patients with H7N9 virus infection were identified among whom, nine (32.1%) died. The median age of fatal cases was significant higher than nonfatal cases (P<0.05). Patients with older age were more strongly associated with increased odds of death (OR = 30.0; 95% CI, 2.85-315.62). Co-morbidity with chronic lung disease and hypertension were risk factors for mortality (OR = 14.40; 95% CI, 1.30-159.52, OR = 6.67; 95% CI, 1.09-40.43, respectively). Moreover, the presence of either bilateral lung inflammation or pulmonary consolidation on chest imaging on admission was related with fatal outcome (OR = 7.00; 95%CI, 1.10-44.61). Finally, dynamic monitoring showed that lymphopenia was more significant in fatal group than in nonfatal group from day 11 to week five (P<0.05). The decrease in oxygenation indexes were observed in most cases and more significantly in fatal cases after week three (P<0.05), and the value of nearly all fatal cases were below 200 mmHg during our evaluation period.
  
  
  CONCLUSIONS
  Among cases with H7N9 virus infection, increased age accompanied by co-morbidities was the risk of death. The severity of lung infection at admission, the persistence of lymphocytopenia, and the extended duration of lower oxygenation index all contributed to worsened outcomes of patients with H7N9 virus infection.
authors.affiliation: Department of Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Ji
authors.affiliation: Department of Critical Care Medicine, Nanjing Drum Tower Hospital, Nanjing, Jiangsu, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Gu
authors.affiliation: Suzhou Municipal Center for Disease Control and Prevention, Suzhou, Jiangsu, China.
authors.forename: Li-Ling
authors.initials: LL
authors.lastname: Chen
authors.affiliation: Department of Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Xu
authors.affiliation: Wuxi Municipal Center for Disease Control and Prevention, Wuxi, Jiangsu, China.
authors.forename: Xia
authors.initials: X
authors.lastname: Ling
authors.affiliation: Department of Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Chang-Jun
authors.initials: CJ
authors.lastname: Bao
authors.affiliation: Department of Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Fen-Yang
authors.initials: FY
authors.lastname: Tang
authors.affiliation: Department of Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Xian
authors.initials: X
authors.lastname: Qi
authors.affiliation: The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Ying-Qiu
authors.initials: YQ
authors.lastname: Wu
authors.affiliation: Department of Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Ai
authors.affiliation: Wuxi People's Hospital Affiliated to Nanjing Medical University, Wuxi, Jiangsu, China.
authors.forename: Gu-Yu
authors.initials: GY
authors.lastname: Shen
authors.affiliation: Department of Critical Care Medicine, Nanjing Drum Tower Hospital, Nanjing, Jiangsu, China.
authors.forename: Dan-Jiang
authors.initials: DJ
authors.lastname: Dong
authors.affiliation: Department of Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Hui-Yan
authors.initials: HY
authors.lastname: Yu
authors.affiliation: The First Affiliated Hospital with Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Mao
authors.initials: M
authors.lastname: Huang
authors.affiliation: The First Affiliated Hospital with Nanjing Medical University, Nanjing, Jiangsu, China.
authors.forename: Quan
authors.initials: Q
authors.lastname: Cao
authors.affiliation: The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Xu
authors.affiliation: The Second Hospital of Nanjing, Nanjing, Jiangsu, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
authors.affiliation: Nanjing Municipal Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Yang-Ting
authors.initials: YT
authors.lastname: Xu
authors.affiliation: Suzhou Municipal Center for Disease Control and Prevention, Suzhou, Jiangsu, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Xia
authors.affiliation: Wuxi Municipal Center for Disease Control and Prevention, Wuxi, Jiangsu, China.
authors.forename: Shan-Hui
authors.initials: SH
authors.lastname: Chen
authors.affiliation: Wuxi People's Hospital Affiliated to Nanjing Medical University, Wuxi, Jiangsu, China.
authors.forename: Gen-Lin
authors.initials: GL
authors.lastname: Yang
authors.affiliation: The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
authors.forename: Cai-Ling
authors.initials: CL
authors.lastname: Gu
authors.affiliation: Nanjing Municipal Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Guo-Xiang
authors.initials: GX
authors.lastname: Xie
authors.affiliation: Department of Acute Infectious Disease Control and Prevention, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Ye-Fei
authors.initials: YF
authors.lastname: Zhu
authors.affiliation: Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Feng-Cai
authors.initials: FC
authors.lastname: Zhu
authors.affiliation: Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu, China.
authors.forename: Ming-Hao
authors.initials: MH
authors.lastname: Zhou
mesh_terms: D000368:Aged; D000818:Animals; D001717:Birds / Q000821:virology*; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D064766:Influenza A Virus, H7N9 Subtype / Q000502:physiology*; D005585:Influenza in Birds / Q000821:virology*; D007251:Influenza, Human / Q000453:epidemiology* / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D016019:Survival Analysis; D016896:Treatment Outcome