Family Relationship, Water Contact and Occurrence of Buruli Ulcer in Benin

Abstract

Background Mycobacterium ulcerans disease (Buruli ulcer) is the most widespread mycobacterial disease in the world after leprosy and tuberculosis. How M. ulcerans is introduced into the skin of humans remains unclear, but it appears that individuals living in the same environment may have different susceptibilities.ObjectivesThis study aims to determine whether frequent contacts with natural water sources, family relationship or the practice of consanguineous marriages are associated with the occurrence of Buruli ulcer (BU).DesignCase control study.SettingDepartment of Atlantique, Benin.SubjectsBU-confirmed cases that were diagnosed and followed up at the BU detection and treatment center (CDTUB) of Allada (Department of the Atlantique, Benin) during the period from January 1st, 2006, to June 30th, 2008, with three matched controls (persons who had no signs or symptoms of active or inactive BU) for age, gender and village of residence per case.Main Outcomes MeasuredContact with natural water sources, BU history in the family and the practice of consanguineous marriages.ResultsA total of 416 participants were included in this study, including 104 cases and 312 controls. BU history in the family (p<0.001), adjusted by daily contact with a natural water source (p = 0.007), was significantly associated with higher odds of having BU (OR; 95% CI = 5.5; 3.0–10.0). The practice of consanguineous marriage was not associated with the occurrence of BU (p = 0.40). Mendelian disorders could explain this finding, which may influence individual susceptibility by impairing immunity.ConclusionThis study suggests that a combination of genetic factors and behavioral risk factors may increase the susceptibility for developing BU.

Elucidation of Macroeconomic Determinants for Prognosis of Buruli Ulcer

“…Therefore, when the population in these African countries can have the access to improved water source, incidences of this disease fall. This phenomenon bolsters the disease transmission model [17] [18] that suggests the pathogen transferred to terrestrial mammal or human acting as hosts for infection spread. "Mysterious disease" Buruli Ulcer thus may spread from biting of such aquatic hemiptera insect (common name Water strider, Gerris sp.…”

Epidemiology and disease burden of Buruli ulcer: a review

“…A number of case-control studies allowed for the direct identification of potential risk factors for contracting the disease (Table 2). 6,[73][74][75][76][77][78][79][80][81][82][83][84][85][86][87] A review article evaluating identified risk factors was published in 2010. 88 …”

“…In accordance with the prevailing assumption that M. ulcerans infection foci are associated with wetlands, most of the case-control studies conducted identified contact with or proximity to water bodies as a risk factor for contracting BU. 6,74,[76][77][78]80,[83][84][85][86][87] Common factors associated with a lower risk for BU reported in several comparative studies were wound care and hygiene 73,76,77,80,83,84 as well as wearing protective clothing. 6,73,76,77,84 In southeastern Australia, exposure to mosquitoes was identified as an additional risk, 73 implicating mosquitoes in the transmission of M. ulcerans in this region.…”

“…In one of the case-control studies conducted in Benin, a history of BU in the family was associated with an increased risk of BU. 74 Whether family relationships of BU are due to genetic factors or simply due to similar exposure to the pathogen remains to be investigated. Only one human host genetic study has been published so far, reporting that susceptibility to BU may be associated with a polymorphism in a NRAMP gene, which had already been associated with tuberculosis and leprosy.…”

Chemistry of natural waters and its relation to Buruli ulcer in Ghana

“…Still others have found that direct contact with aquatic environments is a major risk factor (Aiga et al, 2004;Raghunathan et al, 2005;Debacker et al, 2006;Sopoh et al, 2010), and M. ulcerans has been detected in fish (Eddyani et al, 2004), aquatic snails (Marsollier et al, 2004), aquatic insects (Portaels et al, 1999), and submerged terrestrial plants (McIntosh et al, 2014). While the culturing of M. ulcerans from an aquatic invertebrate (Portaels et al, 2008) suggested a potential reservoir or vector for BU (e.g., Merritt et al, 2010), Benbow et al (2008) discounted predatory aquatic insects as a potential vector because the number of insects and presence of M. ulcerans in these insects are similar at BU-endemic and non-endemic sites.…”