The epidemiology of leptospirosis in Palau

Leptospirosis has been a longstanding problem in Palau, and Public Health programs were implemented in 2000 to conduct surveillance for cases of the disease. Epidemiologic analysis of leptospirosis cases is needed to describe disease occurrence in Palau and to help target prevention and control efforts.

Case data were collected from the Palau Ministry of Health's Reportable Disease Surveillance System. Descriptive epidemiology was performed on the case data, and spatial analysis was used to assess the distribution of leptospirosis cases in Palau.

Between May of 2000 and June of 2006, 81 cases of leptospirosis occurred in Palau. Characteristics of the case population included being male (72.8%), being Palauan (70.4%), having an indoor occupation (71.0%), and living in an urban area of Palau (80.3%). It was also found that non-Palauan cases were significantly more likely to die of leptospirosis compared to the Palauan cases (p = 0.0018). Non-Palauan cases were significantly more likely to live in rural areas of Palau (p = 0.0001). There was no significant difference in the disease risk when comparing urban and rural areas. The crude disease risk for Palau is 401.9 (95% Cl 313.8-489.9) cases per 100,000 for the 6.2-year study period, and the average annual risk was 65.2 per 100,000.

Leptospirosis continues to be present in Palau, and prevention and control measures should be continued and targeted toward specific states and hamlets of Koror. Furthermore, non-Palauan populations should be targeted for interventions to prevent more severe outcomes of this disease.