An association between using coastal waters for recreation and staphylococcal skin infections has been reported by canoe paddlers and several physicians in Hawaii. A retrospective epidemiological/microbiological monitoring study was undertaken to determine the association between S aureus skin infections in youngsters (4 months to 16 years of age) and their exposure to recreational use of coastal waters. Telephone interviews were conducted of 53 patients with such skin infections and 53 similar (controlled for age and sex) patients with no infection. A significant association between skin infection and water exposure was found, the odds showing that those developing skin infection caused by S aureus were 4 times more likely to have had a history of seawater contact than the control group. Moreover, the antibiotic sensitivity patterns and phage types of S aureus isolated from patients were similar to those isolated from seawater at bathing beaches.