An Outbreak of Vibrio cholerae O1 infections on Ebeye Island, Republic of the Marshall Islands, associated with use of an adequately chlorinated water source.

In December 2000, physicians in the Republic of the Marshall Islands reported the first known outbreak of Vibrio cholerae O1 infection (biotype El Tor, serotype Ogawa) from this country. In a matched case-control study on Ebeye Island, patients with cholera (n=53) had greater odds than persons without cholera (n=104) to have drunk adequately chlorinated water collected from a US military installation on neighboring Kwajalein Island and transported back to Ebeye (matched odds ratio [MOR], 8.0; P=.01). Transporting or storing drinking water in a water cooler with a spout and a tight-fitting lid was associated with reduced odds of illness (MOR, 0.24; P<.01), as was drinking bottled water (MOR, 0.08; P<.01), boiled water (MOR, 0.47; P=.02), or water flavored with powdered drink mixes (MOR, 0.18; P<.01). No cases of cholera were reported among Kwajalein residents. This outbreak highlights the critical importance of handling and storing drinking water safely, especially during outbreaks of gastrointestinal illness.