The number of human visitors to Antarctica is increasing rapidly, and with it a risk of
introducing infectious organisms to native animals. To study the occurrence of salmonella
serotypes in sub-Antarctic wildlife, faecal samples were collected from gentoo penguins,
macaroni penguins, gray-headed albatrosses, black-browed albatrosses and Antarctic fur seals
on Bird Island in the South Georgian archipelago during the austral summer of 1996 and 1998.
In 1996, S. havana, S. typhimurium and S. enteritidis were isolated from 7% of gentoo
penguins and 4% of fur seals. In 1998, however, 22% of fur seals were found to be infected
with S. havana, S. enteritidis and S. newport.
All isolates, except one, showed identical pulsed-field
gel electrophoresis-patterns within each serotype, irrespective of sampling year and animal
reservoir. No significant antibiotic resistance was found. The very low heterogeneity in the
salmonella isolates found could either indicate a high genetic adaptation of the bacteria to the
environment or a recent introduction of salmonella into the area.