title: [An outbreak of paratyphoid fever in a county of Yunnan province, 2010-2011].
abstract: Objective:To identify the source and to comment on control program regarding an outbreak of paratyphoid A fever in a county, through field studies.Methods:Descriptive epidemiological methods were adopted to describe the epidemiological characteristics of the outbreak, which occurred in Yuanjiang county, Yunan province between 2010-2011, China. Case-control study with environmental investigation was performed to identify related risk factors and pathogens while isolation and susceptibility on the suspected pathogens were conducted. Subsequently, intervention and preventive measures were taken for the control of the outbreak.Results:A total of 600 cases were diagnosed and reported as paratyphoid fever A which spread over the whole Yuanjiang county, including 10 townships with different incidence rates. The disease was spatially clustered and the prevalence rates in these townships decreased with increasing distances from the polluted fields. Data from the case-control study discovered that consumption of raw vegetables was the main risk factor associated with this outbreak of paratyphoid fever (OR=65.3,P<0.001). Management of patients did not meet the requirements while feces and urine of the outpatients polluted the wastewater system in the city.Salmonella paratyphiA isolates were identified from the improperly disinfected wastewaters in hospitals and city systems, respectively. After the measures as prohibiting the planting of vegetables in contaminated fields and disinfection of hospital wastewater were taken, the outbreak subsided.Conclusions:Urban and hospital wastewater used for vegetables irrigation together with the tradition of eating uncooked vegetables seemed responsible for the outbreak of this paratyphoid fever. Intervention programs carried by the local government played a key role in controlling this large outbreak.
authors.affiliation: Division of Infectious Disease Control, Yuxi City Center for Disease Control and Prevention, Yuxi 653100, China.
authors.forename: S K
authors.initials: SK
authors.lastname: Wang
authors.affiliation: Division of Infectious Disease Control, Yuanjiang Prefecture Center for Disease Control and Prevention, Yuanjiang 653300, China.
authors.forename: Z G
authors.initials: ZG
authors.lastname: Wang
authors.affiliation: Division of Infectious Disease Control, Yuanjiang Prefecture Center for Disease Control and Prevention, Yuanjiang 653300, China.
authors.forename: X H
authors.initials: XH
authors.lastname: Zhang
authors.affiliation: Division of Diarrheal Disease, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
authors.forename: B
authors.initials: B
authors.lastname: Yang
authors.affiliation: Division of Infectious Disease Control, Yuxi City Center for Disease Control and Prevention, Yuxi 653100, China.
authors.forename: Q
authors.initials: Q
authors.lastname: Wu
authors.affiliation: Division of Diarrheal Disease, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
authors.forename: B
authors.initials: B
authors.lastname: Kan
authors.affiliation: Division of Laboratory Medicine, Yuanjiang Prefecture Center for Disease Control and Prevention, Yuanjiang 653300, China.
authors.forename: Y H
authors.initials: YH
authors.lastname: Zhou
authors.affiliation: Division of Infectious Disease Control, Yuxi City Center for Disease Control and Prevention, Yuxi 653100, China.
authors.forename: R S
authors.initials: RS
authors.lastname: Yang
authors.affiliation: Division of Diarrheal Disease, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
authors.forename: M Y
authors.initials: MY
authors.lastname: Yan
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D004196:Disease Outbreaks; D004203:Disinfection; D006761:Hospitals; D006801:Humans; D008297:Male; D010284:Paratyphoid Fever / Q000453:epidemiology*; D015995:Prevalence; D012307:Risk Factors; D012482:Salmonella paratyphi A / Q000302:isolation & purification*; D014675:Vegetables / Q000382:microbiology*; D014871:Water Microbiology; D014881:Water Supply
keywords: Epidemiological investigation; Outbreak; Paratyphoid A fever; Salmonella paratyphi A