title: [Avian influenza virus infection in people occupied in poultry fields in Guangzhou city].
abstract: OBJECTIVE
  To conduct serological investigation on H5N1/H9N2/H7N7 infection among people occupied in poultry fields.
  
  
  METHODS
  Serum samples were collected from people working in live poultry and none-poultry retailing food markets, poultry wholesaling, large-scale poultry breading factories and in small-scale farms, wide birds breeding, swine slaughtering houses and from normal population. Antibodies of H5, H9 and H7 with hemagglutination inhibition and neutralization tests were tested and analyzed. Logistic regression and chi(2) test were used.
  
  
  RESULTS
  Among 2881 samples, 4 were positive to H5-Ab (0.14%), 146 were positive to H9-Ab (5.07%) and the prevalence of H9 among people from live poultry retailing (14.96%) was the highest. Prevalence rates of H9 were as follows: 8.90% in people working in the large-scale poultry breading factories, 6.69% in the live poultry wholesaling business, 3.75% in the wide birds breeding, 2.40% in the swine slaughtering, 2.21% in the non-poultry retailing, 1.77% in the rural poultry farmers and 2.30% in normal population. None was positive to H7-Ab among 1926 poultry workers.
  
  
  CONCLUSIONS
  The H5 prevalence among people was much lower than expected, but the H9 prevalence was higher. None of the populations tested was found positive to H7-Ab. There was a higher risk of AIV infection in live poultry retailing, wholesaling and large-scale breading businesses, with the risk of live poultry retailing the highest. The longer the service length was, the higher the risk existed.
authors.affiliation: Guangzhou Center for Disease Control and Prevention, Guangzhou 510080, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: En-jie
authors.initials: EJ
authors.lastname: Lu
authors.forename: Yu-lin
authors.initials: YL
authors.lastname: Wang
authors.forename: Biao
authors.initials: B
authors.lastname: Di
authors.forename: Tie-gang
authors.initials: TG
authors.lastname: Li
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhou
authors.forename: Li-li
authors.initials: LL
authors.lastname: Yang
authors.forename: Xiao-yin
authors.initials: XY
authors.lastname: Xu
authors.forename: Chuan-xi
authors.initials: CX
authors.lastname: Fu
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
mesh_terms: D000328:Adult; D000383:Agriculture; D000818:Animals; D005260:Female; D006801:Humans; D053124:Influenza A Virus, H5N1 Subtype; D005585:Influenza in Birds / Q000453:epidemiology / Q000821:virology; D007251:Influenza, Human / Q000453:epidemiology* / Q000821:virology*; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure; D011200:Poultry