Abstract

18 confirmed human cases of H5N1 sickness coincided with outbreaks of highly pathogenic influenza A (H5N1) in poultry in 1997. Although exposure to live chickens was linked to human sickness, no cases among poultry employees were recorded (PWs). A cohort study involving 293 Hong Kong government employees (GWs) who took part in a poultry culling operation and 1525 PWs was carried out to assess the possibility of H5N1 transmission from birds to humans. When anti-H5 antibodies were detected by both micro neutralization and Western blot analysis, paired serum samples from GWs and single serum samples from PWs were deemed to be anti-H5 antibody positive. One documented seroconversion and 3% of GWs were seropositive. 10% of PWs exhibited anti-H5 antibodies. Anti-H5 antibodies were linked to more intensive chicken exposure, such as butchering and exposure to sick poultry. These data imply that work exposure increases the likelihood of contracting avian influenza.