Investigation of cholera acquired from the riverine environment in Queensland.

Since February 1977, five patients with cholera apparently acquired the infection from the riverine environment in Queensland. A total of 13 rivers have now yielded at least one isolate of Vibrio cholerae 01 biovar El Tor. Investigations indicate that the organism, including toxigenic strains, can survive and multiply in the riverine environment. No human or animal reservoirs and no ecological niches were identified and no route of importation or dissemination of the organism was discovered. The microbiological examination of faeces in all medical laboratories in Australia should include methods for detecting the cholera organism as a routine. When confronted with a cholera infection, medical practitioners should obtain a history of recent travel, both in Australia and overseas.