Epidemiology of Cutaneous Leishmaniasis in West Africa: a Systematic Review

Abstract

Cutaneous leishmaniasis (CL) has been described in West Africa (WA) since the beginning of the 20th century. The incidence of cases has markedly increased during the last decades in several countries of the region. Despite that, data remain scarce and fragmentary. The current incidence and geographic distribution of the disease as well as the involved vectors and reservoirs remain poorly documented. The objective of this review was to collect and analyze available data about CL in WA in order to improve the management of cases and the control of the disease transmission. A systematic literature review was performed using the Pubmed, Google Scholar and Hinari databases. Publications focusing on epidemiological aspects of CL, involved parasite species, sand flies and potential reservoir hosts were searched without any restrictions. Unpublished studies were extracted from Google. Manuscripts without full text or summary available were excluded as well as those whose summaries did not contain any usable data. One hundred and fifteen studies were recorded. Among them, 93 filled selection criteria. CL has been reported in 10 West African countries with outbreaks described in five countries. Burkina Faso, where the average incidence of the disease is around 928 cases per year, and Ghana seem to be the most affected. Cases have been confirmed in the majority of studies by microscopy sometimes associated with culture or histology. The exposure rate to Leishmania infection based on leishmanin skin test was relatively high with an overall average of 30.2%. Leishmania major was the only species identified with a predominance of MON-74 (62%) and MON-26 (30.6%) zymodemes. Phlebotomus duboscqi is retained as the vector whereas Sergentomyia darlingi and Sergentomyia ingrami were found naturally infected. Rodents including Arvicanthis niloticus, Gerbilliscus gambiana and Mastomys spp. are reported as the main reservoir hosts. Additional studies are needed to better characterize CL in WA in order to optimize the management of cases and to organize the control of the disease transmission.