High seroprevalence and associated risk factors of visceral leishmaniasis in the Léré Health District, Chad

Abstract

Visceral leishmaniasis (VL) is a major neglected tropical disease in Chad, particularly in the Léré Health District, where epidemiological data remain scarce. This study aimed to determine the seroprevalence of VL among symptomatic patients and to identify associated sociodemographic, behavioral, and environmental risk factors. A cross-sectional study was conducted from July to October 2022 among patients presenting symptoms suggestive of VL. After obtaining informed consent, participants completed a structured questionnaire capturing demographic, environmental, and behavioral characteristics. Blood samples were collected and analyzed using a rapid diagnostic test (RDT) for VL. Data analysis was performed using XLSTAT software. Among the 303 patients, the seroprevalence of VL was 37.62%. Women represented 55% of participants, and children aged 0-14 years constituted the most affected age group (38.28%). Significant associations were observed between VL positivity and rural residence, low education level, limited knowledge about VL, proximity to forested areas, presence of domestic animals, particularly dogs, and inadequate vector-control practices. VL remains a major public health concern in the Léré district. Transmission is driven by a combination of environmental factors, socio-economic vulnerability, and the presence of zoonotic reservoirs. Urgent action is required to strengthen disease surveillance, expand access to reliable diagnostic services, enhance community awareness, and implement integrated One Health interventions to reduce transmission and protect vulnerable populations.