Leishmania parasites are the causative agents of leishmaniasis. The Visceral leishmaniasis (VL) form of the disease is fatal if not treated in most cases. This study examined the epidemiological aspects of VL in two southwest counties of Iran.

This was a retrospective study of hospitalized patients with a laboratory confirmation of VL from Larestan and Ghiro-Karzin Counties.

For Larestan county, a decline in the incidence of VL has been observed from 2004 to 2015. Significantly more males (n = 14) than females (n = 6) were infected with VL in this county (p < 0.05), >95% of cases in children under 5 years of age. In Ghiro-Karzin county, the results were similar to a decline in VL infection from 2004 to 2015, and slightly more males (n = 14) than females (n = 11). Similarly, the majority of the patients infected with VL were children under 5 years old (88%).

The results from this study indicate that although the incidence of VL infection has reduced over time, VL was more prevalent in boys under 5 years old, suggesting that more attention to controlling the parasite and its vector are required.