Using Ecosystem Approach to Address Infection with Leishmania Major in Central Tunisia

Abstract

Background: Cutaneous leishmaniasis is endemic in many parts of the world. There are about twenty different species of Leishmania capable of infecting humans. The distribution of cutaneous leishmaniasis is very closely related to the geographical characteristics and the ecological specificities of the endemic areas. Zoonotic Cutaneous Leishmaniasis (ZCL) is the most common form of leishmaniasis in Tunisia. We used Eco Health Approach to understand if and how farming practices in two communities in Central Tunisia affect farmers’ exposure to P. papatasi, the vector of ZCL. Methods: We reviewed irrigation records and conducted site visits and interviews with community members and entomological investigation in 2 rural areas (Hichria and Ouled Mhamed) in Sidi Bouzid, Central Tunisia. Results: In Hichria, relatively intensive farming, combined with inefficient surface irrigation technology and limited irrigation capacity, results in a need for nighttime irrigation activity. In Ouled Mhamed (Bir Badr), farmers used more efficient sprinkler and drip irrigation techniques. The aging infrastructure and limited economic opportunities from farming have discouraged investment in more intensive agriculture. Farming is mostly limited to end-of-season olive production. Local demand for irrigation is easily met in daytime hours. In Hichria, female P. papatasi was present in the irrigation zone and in livestock shelters nighttime. Leishmania DNA was detected in 20 of 241 females in this area including 8 in the irrigated zone. Farming practices in Hichria require farmers to irrigate at night, increasing their exposure to the ZCL vector and hence their risk of infection. In nearby Ouled Mhamed, because of different farming practices, farmers do not engage in nighttime irrigation and thus do not face this same exposure. Conclusion: Economic strategies (e.g. intensity of agriculture, crop choices, and animal husbandry), technology (e.g. surface vs. drip irrigation) and institutional arrangements (e.g. community responses to meet irrigation needs) may be important human environment determinants of ZCL risk. Interventions targeting these same factors may help reduce risks of ZCL infection, complementary to more conventional vector control and case detection and treatment, where they exist. Citation: Bellali H, Saffar F, Ben Alaya Bouafif N, Nouiri I, Ghrab J, et al. (2019) Using Ecosystem Approach to Address Infection with Leishmania Major in Central Tunisia. Arch Epidemiol 3: 1028. DOI: 10.29011/2577-2252.101028 2 Volume 3; Issue 01 Arch Epidemiol, an open access journal ISSN: 2577-2252 Author Summary Research on the ZCL in Tunisia has mostly focused on • disease epidemiology, including more recently on its ecoepidemiology and the environmental determinants of risk, and on clinical research. There has been virtually no attention to the human environmental determinants of risk. This paper is the first-ever research work, using Eco Health approach, to study the effect of different agricultural regimes on ZCL exposure in Tunisia. A combination of factors (farming intensity, crop choices, irrigation technology and management) required one community to practice nighttime irrigation, thus increasing their exposure to the lone vector of ZCL, the nocturnal sand fly P. papatasi. Understanding of human environmental determinants suggests of new possibilities for ZCL prevention that are cost-effective and practicable in the near-term in Tunisia and other endemic-epidemic regions.