Effects of closing and reopening live poultry markets on the epidemic of human infection with avian influenza A virus

Live poultry markets（LPMs） are crucial places for human infection of influenza A（H7N9 virus）.In Yangtze River Delta,LPMs were closed after the outbreak of human infection with avian influenza A（H7N9） virus,and then reopened when no case was found.Our purpose was to quantify the effect of LPMs＇ operations in this region on the transmission of influenza A（H7N9） virus.We obtained information about dates of symptom onset and locations for all human influenza A（H7N9） cases reported from Shanghai,Jiangsu and Zhejiang provinces by May 31,2014,and acquired dates of closures and reopening of LPMs from official media.A two-phase Bayesian model was fitted by Markov Chain Monte Carlo methods to process the spatial and temporal influence of human cases.A total of 235 cases of influenza A（H7N9） were confirmed in Shanghai,Jiangsu and Zhejiang by May 31,2014.Using these data,our analysis showed that,after LPM closures,the influenza A（H7N9） outbreak disappeared within two weeks in Shanghai,one week in Jiangsu,and one week in Zhejiang,respectively.Local authorities reopened LPMs when there was no outbreak of influenza A（H7N9）,which did not lead to reemergence of human influenza A（H7N9）.LPM closures were effective in controlling the H7N9 outbreak.Reopening of LPM in summer did not increase the risk of human infection with H7N9.Our findings showed that LPMs should be closed immediately in areas where the H7N9 virus is confirmed in LPM.When there is no outbreak of H7N9 virus,LPMs can be reopened to satisfy the Chinese traditional culture of buying live poultry.In the long term,local authorities should take a cautious attitude in permanent LPM closure.

Etiological characteristics of influenza-like illness in Jiangsu province from 2012 to 2016

Influenza-like illness(ILI)is an acute respiratory infection caused by various pathogens.However,the epidemiologic characteristics of ILI pathogens in Jiangsu province are unclear.To better understand the ILI etiology,the characteristics of the pathogens from nasopharyngeal swab samples of patients with ILI collected from 2012 to 2016 in 6 hospitals in Jiangsu province were studied.The pathogens,including influenza virus,respiratory syncytial virus(RSV),rhinovirus(HRV),adenovirus(ADV),herpes simplex virus(HSV),human coronavirus(hCoV),Streptococcus pneumoniae and Haemophilus influenzae,were detected by real-time PCR.At least one pathogen was identified in 1334 of the patients(40.23%).Among viruses,HRV,influenza A virus(Flu A),ADV and RSV were the most frequently detected.ADV was the only pathogen that was distributed evenly in different years and regions(P>0.05).The etiological distribution varied in different age groups.Streptococcus pneumoniae was the most common pathogen in co-infections with a co-detection rate of 64.57%(319/494).The spectrum of etiologies could help to estimate disease burden and provide guidance for vaccination.