A Landscape-based Model for Predicting Mycobacterium ulcerans Infection (Buruli Ulcer Disease) Presence in Benin, West Africa

Abstract

Mycobacterium ulcerans infection (Buruli ulcer [BU] disease) is an emerging tropical disease that causes severe morbidity in many communities, especially those in close proximity to aquatic environments. Research and control efforts are severely hampered by the paucity of data regarding the ecology of this disease; for example, the vectors and modes of transmission remain unknown. It is hypothesized that BU presence is associated with altered landscapes that perturb aquatic ecosystems; however, this has yet to be quantified over large spatial scales. We quantified relationships between land use/land cover (LULC) characteristics surrounding individual villages and BU presence in Benin, West Africa. We also examined the effects of other village-level characteristics which we hypothesized to affect BU presence, such as village distance to the nearest river. We found that as the percent urban land use in a 50-km buffer surrounding a village increased, the probability of BU presence decreased. Conversely, as the percent agricultural land use in a 20-km buffer surrounding a village increased, the probability of BU presence increased. Landscape-based models had predictive ability when predicting BU presence using validation data sets from Benin and Ghana, West Africa. Our analyses suggest that relatively small amounts of urbanization are associated with a decrease in the probability of BU presence, and we hypothesize that this is due to the increased availability of pumped water in urban environments. Our models provide an initial approach to predicting the probability of BU presence over large spatial scales in Benin and Ghana, using readily available land use data.

Landscape Fragmentation as a Risk Factor for Buruli Ulcer Disease in Ghana

“…To date, the use of land cover and landscape pattern metrics as predictors for BU presence or risks has been explored. 7,9,30 However, studies on the relationship between landscape diversity and BU disease are still rare. Brou and others 8 reported that landscape diversity was related to BU in Cote d'Ivoire.…”

L'environnement socio-spatial comme facteur d'émergence des maladies infectieuses

“…La taille du foyer est validée si la probabilité d'apparition d'un nouveau cas est plus importante dans le foyer qu'à l'extérieur par l'analyse de la dispersion de l'apparition de tous les cas sur le territoire. Cette méthode a été validée dans des études du lien spatio-temporel entre l'environnement et des foyers de maladies vectorielles ou non (Johnson, 2006, Hsu, 2007Wagner, 2008).…”

Insertion Sequence Element Single Nucleotide Polymorphism Typing Provides Insights into the Population Structure and Evolution of Mycobacterium ulcerans across Africa

“…Even though the infection affects all age groups, at least half of all cases occur in children under age 15 years (3). More than 30 countries worldwide have reported (but not always confirmed) this emerging disease, with the highest incidence in West and Central Africa, where the disease occurs in foci among people living in rural marshes, wetlands, and riverine areas (1,4). As proximity to these slow-flowing or stagnant water bodies is a known risk factor for M. ulcerans infection (5) and as M. ulcerans DNA has been detected in a variety of aquatic specimens (6,7), it is generally believed that M. ulcerans is an environmental mycobacterium that can initiate infection after microtraumata of the skin (8).…”