Introduction
Visceral leishmaniasis (VL), also known as kala-azar, is a life-threatening disease caused by protozoan parasites of the Leishmania donovani complex. The disease is transmitted to humans by the bite of infected female sand flies. Over the past two decades, VL has seen a resurgence in Ethiopia, with significant concern for public health. This report delves into a thorough research study which advances our understanding of this disease within the Shebelle Zone of the Somali Region in eastern Ethiopia (DOI: 10.1186/s13071-019-3452-5).
The Study
Published on May 21, 2019, in ‘Parasites & Vectors’, researchers Getachew Alebie, Amha Worku, Siele Yohannes, Befikadu Urga, Asrat Hailu, and Dagimawie Tadesse conducted a cross-sectional epidemiological study to assess the seroprevalence, associated factors, and incriminated vectors of VL in Shebelle Zone, eastern Ethiopia (DOI: 10.1186/s13071-019-3452-5).
Methodology
The study, conducted between March and May 2016 in Gode and Adadle districts, employed semi-random sampling for the field survey, where 361 participants were included. It entailed structured questionnaire interviews, serological assays using the rK39-immunochromatographic test, ELISA (Enzyme-Linked Immunosorbent Assay), and entomological surveys to identify the vector sand flies.
Findings
Notably, 15.8% of the participants were seropositive for VL. Adadle district exhibited a significantly higher seroprevalence (31.1%) compared to Gode (12.7%) district. The study also found that VL risk is higher among females, with those under 15 years being the most affected. Risk factors identified include the presence of termite hills, the specific study district, outdoor sleeping habits, the presence of Acacia trees, and proximity to domestic animals.
Vector Identification
The entomological survey identified several species of sand flies, with Phlebotomus orientalis showing a higher frequency of collection in the surveyed areas, especially in Adadle district. A striking conclusion is the identification of potential new VL-transmission foci in the study districts.
Implications of the Study
This groundbreaking research emphasizes the need for further parasitological and molecular studies to confirm the transmission dynamics of VL in the region. It also calls for the implementation of appropriate control measures and public health interventions to mitigate the disease spread.
Future Directions
The authors suggest a comprehensive approach for controlling VL, involving early diagnosis, effective treatment, vector control, and community education. They also advise on the necessity of continuous surveillance to adapt strategies in the face of changing epidemiological patterns and environmental factors linked to VL.
Conclusion
This study provides critical epidemiological data on VL in an understudied area, highlighting the variability in disease prevalence across different districts and risk factors that could guide targeted control measures. Policymakers and health authorities in Ethiopia are encouraged to use these findings to strengthen VL control programs.
References
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Keyword
1. Visceral Leishmaniasis Ethiopia
2. Leishmaniasis Shebelle Zone
3. Phlebotomus orientalis Ethiopia
4. Kala-azar Epidemiology
5. Sand fly vectored diseases Ethiopia