Leishmaniasis in Sri Lanka: spatial distribution and seasonal variations from 2009 to 2016

Abstract

BackgroundLeishmaniasis is listed as one of the eight neglected tropical diseases by the World Health Organization and the number of cases in endemic areas has seen a sharp rise in the past decade. More alarmingly, reports have shown that leishmaniasis is spreading to non-endemic areas of the world due to co-infection with HIV. In Sri Lanka, leishmaniasis is considered as a notifiable disease from 2008 and has seen a rising trend of incidence since then. This is the first study describing the burden, seasonal variation and spatial distribution of leishmaniasis in Sri Lanka since the disease has been included as a notifiable disease.MethodsData on health statistics from 2009 to 2016 were obtained from published databases maintained by the Epidemiology Unit of the Ministry of Health in Sri Lanka. Climatic data for Sri Lanka were obtained from the Department of Meteorology and the populations in administrative districts were obtained from the Department of Census and Statistics, Sri Lanka. Descriptive spatiotemporal analysis, correlation between leishmaniasis incidence and climatic variables were analyzed using SPSS statistical software.ResultsThe total number of people reported with leishmaniasis during the study period was 8487. Cutaneous leishmaniasis is the prominent form in Sri Lanka while few visceral and muco-cutaneous cases were reported. Although leishmaniasis patients were identified from all 25 districts in the island, almost 90% of the total caseload was reported from Anuradhapura, Hambantota, Polonnaruwa, Kurunegala and Matara districts. The highest number of patients was reported from the Anuradhapura district and the highest incidence per 100,000 persons was reported from the Hambantota district. The disease has a seasonal trend, a peak of leishmaniasis occur in July to September in the north-central region and in October to December in the southern region. Maximum temperature, humidity and wind speed are significantly associated climatic variables with leishmaniasis in endemic regions.ConclusionsLeishmaniasis is an emerging public health problem in north-central and southern Sri Lanka. Public awareness programs for the prevention and control of the disease in endemic regions are essential to reduce the incidence of leishmaniasis.

Is Leishmaniasis adequately notified in Sri Lanka? A survey among doctors from an endemic district, Sri Lanka.

“…Leishmaniasis has now been identi ed as an emerging disease in Sri Lanka (14). Emphasizing the need for controlling this disease Ministry of health, Sri Lanka declared it as a noti able disease in 2008 (15). As expected, doctors were more knowledgable about the clinical features, causative organism, disease transmission and the vector of Leishmaniasis compared to the studies done in general public (16,17).…”

Epidemiology of cutaneous leishmaniasis in a newly emerging focus in Gampaha district, Western province of Sri Lanka

“…Our ndings indicate that there is spatial expansion of CL transmission in Sri Lanka involving hitherto non-endemic regions in the wet zone of the country. The districts of Anuradhapura, and Polonnaruwa in the North Central province, and Hambantota in the Southern province of Sri Lanka were the initial hotspots of CL [24]. More recently (2014-2016), the district of Kurunegala in the North Western province has become a major hotspot for CL [24].…”

“…Although cases of CL have been documented throughout the country, the large majority (over 90%) is usually from the North Central, North Western and Southern provinces [24]. A very low number of cases have been identi ed in the Western province, which includes Colombo, Gampaha and Kalutara districts [24]. Thus, CL was an infrequent infection in the district of Gampaha until recently.…”

Literature review and a preliminary study on leishmaniasis to inform community awareness campaigns in Sri Lanka

“…20 A seasonal trend of leishmaniasis was found in a study which evaluated the data available from 2009 to 2016 and a peak was shown in the period between July to September in the north-central region and in October to December in the southern region. 21…”