title: [A survey of Japanese encephalitis antibody migrant workers in Shenzhen 2009].
abstract: OBJECTIVE
  To understand the immunological status of Japanese encephalitis (JE) antibodies amongst migrant workers and to provide epidemiological basis for public health strategies on JE prevention and control in Shenzhen.
  
  
  METHODS
  A multi-stage random sampling method was used, and 1003 migrant workers aged 18 to 60 from 44 factories were investigated and their serum specimens were collected. The enzyme-linked immunosorbent assay (ELISA) was used to detect JE antibodies qualitatively.
  
  
  RESULTS
  The gross IgG seroprevalence rate for JE was 20.2% (203/1003). Sex-specified seroprevalence was 21.2% (103/485) for male and 19.3% (100/518) for female, respectively (χ(2) = 579, P > 0.05). Age-specific seropositive rates were 22.6% (12/53) for those below 20 years old, 18.7% (120/642) for those between 20-years old, 26.0% (58/223) for those between 30-years old and 15.3% (13/85) for those on or above 40 years old (χ(2) = 7.96, P > 0.05). Proportions for self-reported positive immunization, non-immunization and unclear immunization history were 22.1% (30/136), 22.1% (51/231) and 19.2% (122/636), respectively (χ(2) = 501, P > 0.05). Seroprevalence by region of origins showed that workers from Guangdong province was the highest (30.5%, 50/164), followed by workers from Guangxi (29.7%, 22/74) whilst workers from Shan(3)xi (5.4%, 2/37) had the lowest rate. Seroprevalence rate for managers (29.0%, 31/107) was higher than that of technicians (7.1%, 1/14) (χ(2) = 21.78, P < 0.05). Serological positive rate of workers with university or above educational background was the highest (32.7%, 16/49), followed by that for individuals with college degree (10.3%, 10/97) (χ(2) = 13.02, P < 0.05).
  
  
  CONCLUSIONS
  No associations are detected between JE seroprevalence and age, or sex, or self-reported immunization histories amongst migrant labor workers in Shenzhen. However, correlations between JE serological positive rate and region of origins, occupation and educational attainment are found to be significant. The gross seroprevalence of JE antibodies suggests that the level of JE antibodies amongst Shenzhen migrant workers is low and the population immunity barrier has yet to be established. It is necessary to strengthen prevention and control strategies of JE among labor workers of Shenzhen.
authors.affiliation: Shenzhen Center for Disease Control and Prevention, Shenzhen 518020, China.
authors.forename: Fu-xiang
authors.initials: FX
authors.lastname: Shan
authors.forename: Jin-quan
authors.initials: JQ
authors.lastname: Cheng
authors.forename: Jin
authors.initials: J
authors.lastname: Mou
authors.forename: Shi-ying
authors.initials: SY
authors.lastname: Zhang
authors.forename: Ya-qing
authors.initials: YQ
authors.lastname: He
authors.forename: Jin-hui
authors.initials: JH
authors.lastname: Xiao
authors.forename: Ying-jian
authors.initials: YJ
authors.lastname: Chen
authors.forename: Wen-guang
authors.initials: WG
authors.lastname: Huang
authors.forename: Liang-en
authors.initials: LE
authors.lastname: Xiong
mesh_terms: D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D002681:China / Q000453:epidemiology; D004672:Encephalitis, Japanese / Q000453:epidemiology / Q000517:prevention & control*; D005260:Female; D006801:Humans; D022321:Japanese Encephalitis Vaccines / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D014171:Transients and Migrants / Q000706:statistics & numerical data*; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D022321:Japanese Encephalitis Vaccines