Seroepidemiological study on visceral leishmaniasis in an endemic focus of central Iran during 2017.

Visceral leishmaniasis (VL) is a serious parasitic disease that occurs in some areas of Iran as endemic and sporadic forms. Qom province in central Iran is one of the endemic foci of VL, which is an important issue due to existence of local population density, foreign travelers and resided migrants. This descriptive cross-sectional study that was conducted with the aim of evaluating seroprevalence of VL in the studied area. The research considers various risk factors like immigration and tourism for planning prevention and disease control programs. Random cluster sample selection applied and 960 blood samples collected from children up to 12 years of age. The samples were taken from 22 villages in four clusters, during 2017. A questionnaire was given to each individual after obtaining parental consent. All collected sera assessed by Direct Agglutination Test to detect anti-Leishmania infantum antibodies. The antibody titers of ≥ 1:3200, accompanied by clinical symptoms, considered as VL disease. Eventually, 3 (0.3%) cases showed anti-L. infantum antibodies with titers of ≥ 1:1600, while 2 of them (0.2%) had antibody titers of 1:3200 with no clinical manifestations. In order to investigate the increase of antibody, resampling performed after 2-3 weeks in which no antibody rising observed. The findings indicate that distribution pattern of VL is changing from endemic to sporadic form in rural areas of Qom province. Therefore, it is necessary to continue the surveillance by public health centers besides conducting further studies on VL reservoirs and vectors with the aim of VL control in the area.