Prevalence of Leishmania donovani Infection in Humans and Dogs in Gadarif State, Sudan: A Diagnostic Comparison

Abstract

Background: Leishmania donovani is a protozoan parasite that causes visceral leishmaniasis, a potentially fatal disease in humans and  dogs. The epidemiology and transmission dynamics of L. donovani in Sudan are poorly understood. We aim to determine the prevalence  and characterization of L. donovani in human hospital cases and domestic dogs using different diagnostic methods in two localities in  Gadarif State, Sudan.

Methods: A cross-sectional study was conducted from October 2019 to April 2020. Whole blood samples and lymph  node aspirates were collected from 69 human and 32 dog participants for parasitological, immunological, and molecular tests.

Results:  No parasites were detected in blood samples from either humans or dogs. Lymph node microscopy revealed 71.01% positivity in humans  and 9.4% in dogs. The IT Leish test showed 82.6% positivity in humans and 43.75% in dogs. PCR confirmed L. donovani infection in all six  selected samples (three from humans and three from dogs).

Conclusion: The study confirmed the presence of L. donovani in both  human and dog populations in the study area, suggesting that dogs may act as reservoirs or hosts for the parasite. The IT Leish kit test  was the most sensitive and specific method, while microscopy of blood and lymph node smears was the least sensitive method. Further  studies are needed to elucidate the role of dogs in the transmission cycle of L. donovani and the risk factors associated with human  infection.