Elimination of visceral leishmaniasis as a public health problem in Kenya – progress and challenges

Overview

Leishmaniasis is one of several endemic neglected tropical diseases (NTDs) in Kenya. The disease occurs mainly in 3 clinical forms: visceral leishmaniasis (VL), cutaneous leishmaniasis (CL) and mucocutaneous leishmaniasis (MCL). This article addresses VL in Kenya.

Kenya is currently among the 10 countries that together report over 90% of new cases of VL annually worldwide. The disease was first described in Kenya in 1935 in the northern districts of Mandera and Wajir. Most cases of VL are reported in arid and semi-arid areas in the Rift Valley, Eastern region and the Northeastern regions. VL endemic areas are found in 11 of the 47 counties of the country: Baringo, Garissa, Isiolo, Kajiado, Kitui, Marsabit, Mandera, Tharaka Nithi, Turkana, Wajir and West Pokot. Foci of anthroponotic transmission predominate and are due to Leishmania donovani. The proven sand fly vectors are Phlebotomus martini and Ph. orientalis. Ph. martini is closely associated with Macrotermes termite hills, while Ph. orientalis is associated with Acacia and Balanites woodlands. Neither vector species is synanthropic.

Methods

To determine trends in the number of cases, we analysed data since 2005 available from the WHO Global Health Observatory (GHO). We also analysed other indicators of the distribution of cases according to patient type (new, relapse), monthly distribution of cases, distribution of cases by age and sex, HIV-VL coinfection, PKDL, cases in other endemic counties, and treatment outcome. Data from all leishmaniasis service delivery centres reporting in the country were used. Of 1428 health facilities in endemic counties, 43 are treatment and diagnostic centres, while 84 are testing centres.

Results

Trends over time Since 2005, a total of 13 143 cases have been reported, with a peak of 1746 cases in 2021. Since 2017, ≥1000 cases have been reported, except in 2018, when only 590 cases were reported. No data were available for 2010.