Demographic, Clinical and Bacteriological Characteristics of Human Leptospirosis in Sri Lanka: A Retrospective Study

The clinical and laboratory diagnosis of human leptospirosis is complex due to a variety of factors, but the Microscopic Agglutination Test (MAT) is probably the most specific laboratory test. We describe the demographic, clinical and bacteriological features of all MAT-confirmed cases in 2015 at the National Reference Laboratory in Sri Lanka. The majority of cases had acquired the infection through indirect transmission through high-risk occupations, which relate to the lower socio-economic groups, and a majority was from the economically productive age group. A second sample during follow-up was useful. The common prevalence of serogroups such as Tarassovi and Autumnalis implicate the buffaloe as an important carrier animal in Sri Lanka. There was no significant association between organ involvement and province, except for multi-organ dysfunction syndrome. Several significant associations between serovar and organ involvement were found which could be useful for future pathophysiological studies. Serogroups Australis and Cyanopteri were found significantly more commonly in Uva Province. Awareness of the disease among high risk groups and bovine vaccination programs with locally prevalent serovars should be urgently considered for this potentially fatal disease.