Avian influenza and poultry workers, Peru, 2006

Currently numerous countries in Asia, Africa and Europe are encountering highly pathogenic avian influenza (AI) infections in poultry and humans. In the Americas, home of the world's largest poultry exporters, contingency plans are being developed and evaluated in preparation for the arrival of these viral strains.

With this cross-sectional study, to our knowledge the first in its kind in Central or South America, we sought to learn if Peruvian poultry workers had evidence of previous AI infection and if so, to determine risk factors for infection.

We performed a cross-sectional seroprevalence study among 149 workers on a Peruvian poultry farm (133 exposed to poultry and 17 non-exposed controls), serum samples were tested for human influenza virus exposure using a hemagglutination inhibition (HI) assay. Microneutralization assays were performed on all serum samples to detect antibodies against prototypic avian influenza (AI) strains H4 through H12.

Using multivariate proportional odds modeling we found that the prevalence of elevated titers against AI viruses was low in both groups, exposed and non-exposed controls.

No evidence of previous avian influenza infection among Peruvian poultry workers was found in this first cross-sectional study performed in South America. This first occupational study of AI in Latin America was encouraging, but it likely reflects the sector of poultry production with higher biosecurity.