Epidemiological investigation of severe leptospirosis in the parish of St. Andrew, Barbados

ABSTRACT

The parish of St. Andrew has been shown to have the highest incidence of leptospirosis in Barbados (40/100 000 for the period 1979-1991 inclusive, compared with the mean incidence for the whole island over the same period of 13.3/100 000). A survey was conducted to try to identify which of the known risk-factors for leptospirosis were common in St. Andrew. Thirty-six cases of laboratory-confirmed leptospirosis occurring in the parish were identified during the 14 years from January 1980 to December 1993 inclusive. The incidence of leptospirosis in St. Andrew over this period showed a close association with mean monthly rainfall. However, there was no relationship between individual cases and rainfall in the preceding months. A questionnaire was administered to 71 percent of the thirty-one available subjects. The most common occupations were students (23 percent) agricultural workers (20 percent) while the unemployed were 17 percent. Gardening was practised by 40 percent of the respondents; 63 percent kept livestock animals and 86 percent kept dogs. Exposure to ponds or other water was common (41 percent) and 23 percent of respondents admitted walking barefoot some or all of the time. Mongooses were seen near the home or workplace by eight (36 percent) respondents, rats by 16 (73 percent), mice by 13 (59 percent) and frogs or toads by 14 (64 percent). The patients who responded to this questionnaire were exposed to multiple risk factors. Few indicated a change in lifestyle since recovering from leptospirosis. The importance of education for preventing exposure must be emphasized (AU)