Benthic invertebrate metrics associated with Buruli ulcer disease and its etiologic agent in Ghana, West Africa

Several laboratory studies have associated the etiologic agent of Buruli ulcer disease, Mycobacterium ulcerans, with specific biting hemiptera; the implication being that these bugs could act as vectors. Other studies have associated disease with disturbed aquatic habitats. The objective of this study was to identify invertebrate community metrics associated with the cases of disease and/or pathogen presence in aquatic habitats among 98 sites in Ghana, Africa. We assayed the dominant plant macrophyte communities and water column seston for M. ulcerans in the same habitats where invertebrates were collected in a standardized method common to aquatic biomontoring programs. We found that after accounting for waterbody type (lentic/lotic), there were significant differences in certain metrics between disease endemic sites and sites where the pathogen was detected. In lentic habitats, percent Diptera was significantly greater in disease endemic compared to non-endemic sites, while eveness was significantly higher in non-endemic sites, indicating possible associations with eutrophication. In lotic habitats, percent Belostomatidae was significantly greater in disease endemic sites, with other differences found for functional feeding group metrics. These results suggest that invertebrate communities of these aquatic habitats may be useful sentinels for initial identification of pathogen presence or habitat conditions associated with disease transmission.