Mycobacterium leprae infection, Hansen’s disease, and helminth infections: A cross-sectional study in southeastern Brazil

Background Neglected tropical diseases are often co-endemic in affected areas but how they interact is less clear, especially in the case of Hansen’s Disease (HD), commonly referred to as leprosy. Prior studies have demonstrated associations between helminths and HD and tuberculosis, but our understanding of the epidemiology of these infections is limited. Our goal was to assess the prevalence and potential associations of Mycobacterium leprae infection and parasitic infections in a sample of community members in a highly endemic area for HD in Minas Gerais, Brazil. Methods Adults and children ages 3 years and older were enrolled from communities in Governador Valadares, Minas Gerais, Brazil, and nearby municipalities. Questionnaires on demographics and infection history were administered. Serological reactivity against M. leprae , Schistosoma mansoni, and Strongyloides stercoralis was assessed by multiplexed bead assay (MBA). Descriptive, univariate, and multivariate statistics were performed to describe the outcomes and potential associations. Results Of 1,311 participants, 72 (5.5%) reported a prior history of HD, 94 (7.2%) tested positive for anti-LID-1, 836 (63.8%) reported having one or more parasitic diseases in the past, 153 (11.7%) tested positive for antibodies to schistosoma egg antigen (SEA), and 69 (5.3%) for antibodies to the Strongyloides stercoralis antigen, NIE. Rural residence and anti-LID-1 showed a positive association (aOR 1.79, CI: 1.07- 3.38) as did rural residence and history of HD (aOR, 1.97, CI: 1.14 – 3.38). While not statistically significant, there was a positive association between anti-LID-1 and NIE antibodies (aOR 1.57, CI: 0.69-3.57), and a negative association between anti-LID-1 and SEA antibodies (aOR 0.79, CI: 0.38 - 1.61). Conclusion We simultaneously measured seroreactivity among various pathogens. While we did not find that a history of HD and anti-LID-1 positivity were associated with seropositivity to NIE or SEA, our study found a high burden of several neglected tropical diseases (NTDs). There was also a strong association with rural residence and LID-1 positivity warranting investigation into the prevalence and epidemiology of M. leprae infection, as well as potential spatial and environmental risk factors.