Buruli ulcer and the effect of water quality on aquatic macroinvertebrate communities of Ghana, Africa

Buruli ulcer (Mycobacterium ulcerans infection) is an emerging skin disease resulting in ulcerations that can lead to severe and lasting morbidity. This disease is primarily found in tropical and subtropical climates with the highest number of reported cases occurring in developing West African nations. The mode of BU transmission remains unclear, however, incidence of human infection is commonly linked to freshwater environments, with higher prevalence associated with increased land use and decreased water quality. Aquatic invertebrates have been considered likely environmental reservoirs of M. ulcerans and aquatic biting insects suggested as potential vectors of BU to humans, yet, much is still unknown regarding the ecology of these insect communities and how they respond to changes in the environment. Our research objectives were to (1) identify macroinvertebrate community structure and function within waterbodies of regions known for Buruli ulcer and (2) identify relationships between these macroinvertebrate communities and water quality. During August 2005, macroinvertebrate samples were collected from littoral habitats of twenty waterbodies from Ghana, Africa, and multivariate statistical methods were used to identify relationships among all variables. Preliminary data suggest the predator communities, which include biting aquatic insects, positively respond to decreased water quality. Knowledge of these relationships, between macroinvertebrates and water quality, could be utilized in understanding Buruli ulcer occurrence, transmission, and in predicting future disease incidence.