Analysis of Hospital-Based Sentinel Surveillance Data on Leptospirosis in Sri Lanka, 2005-2008

In Sri Lanka, leptospirosis is a notifiable disease. In addition to having a routine disease reporting system, Sri Lanka has implemented a hospital-based sentinel surveillance system since 2004. This report discusses the findings of a descriptive analysis of the sentinel surveillance data collected from 2005 to 2008. Of the 4,000 suspected leptospirosis cases, 46.9z and 26.8z were recorded from the Western and Sabaragamuwa provinces, respectively. Most of the individuals were male (83.5z), and approximately 45.6z were aged 30–49 years. Farmers accounted for 16.5z, and laborers for 16.1z; however, the occupation of nearly half (44.8z) of the study population was unknown. More than half (53.9z) of the individuals worked in paddy fields. Almost all had acute fever (98.8z), myalgia (92.9z), and headache (92.7z), but fewer had other related symptoms. Out of the 4,000 individuals, 2,496 (62.4z) underwent a laboratory test; however, the laboratory test results of only 1,445 (57.9z) and the microscopic agglutination results of only 41 (2.8z) were available at the sentinel sites. Less than 2z of the reported individuals underwent prophylactic treatment. These findings will help enhance the ongoing efforts for controlling and preventing leptospirosis in Sri Lanka. Sentinel surveillance is a useful tool, but the data quality needs to be improved by supplementing the findings with adequate laboratory diagnosis data.