Introduction Buruli ulcer(BU) disease is caused by infection with the environmental pathogen Mycobacterium ulcerans (M. ulcerans) and largely affects the skin, often progressing without pain or fever to the patient [1] . The possibility of BU being transmitted from person-to-person is not properly investigated, however infection is based on direct or indirect contact with M. ulcerans in the environment. Studies have commonly implicated M. ulcerans with aquatic environments [2, 3]; however,

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... e is available on the ecology of the pathogen and its geographical distribution in the environment [4] . Portaels, et al. [5] proposed an interesting hypothesis for a possible mode of transmission to humans through waterfiltering hosts (fish, mollusks) that cluster the MU bacteria available in water or mud and then discharge them again to the environment. They are then ingested by aquatic predators including water bugs which eventually transmit the disease through biting of humans [6] . The temperate and tropical environments provide the best condition for water bugs to strive in freshwater. They prey, based on their size, on snails, small fishes, mollusks and larvae of some insects they obtain with their raptorial front legs and bite using their rostrum. Studies conducted in West Africa and other places have associated certain aquatic insects as probable candidate in the transmission of MU from a natural source to humans [7, 8] . In the endemic areas in Ghana, water bugs are in abundance particularly in swamps and rivers in which human activities including farming, fishing, bathing occur [6] . The effect of BU on affected communities is disturbing since BU brings about permanent disabilities relatively over 25% of its victims [9, 10]. Mathematical modeling in epidemiology offers new phase in understanding the spread of diseases, and it gives suggestions how disease should be controlled [11] . A well-constructed mathematical model is capable of providing a deeper insight into the process of disease transmission [12, 13] . Fractional calculus provides a broad frame work in modeling technique in the context of epidemiology. For some recent work on fractional differential equations (see [14, 15] [. Currently, it has been established that several phenomena in diverse fields can be explained successfully by the models applying fractional order differential equations [16] . Main assertion is that a fractional model can bring about a more realistic explanation to natural phenomena. In this paper, we take into account the fractional order SIR model which is connection with the evolution of Buruli ulcer disease in human population. Qualitative dynamics of the model is determined and studied including the basic reproduction number, R 0 . We present a detailed analysis for the asymptotic stability of disease-free and positive fixed points. Numerical simulations are provided to authenticate the obtained results.   Abstract: Mycobacterium ulcerans (MU) has been recognized to be the cause of Buruli ulcer (BU). The association between the ulcer and environmental exposure is identified as a potential factor of spreading BU. The invariant region of the model is determined. In this paper, we explored the power of fractional order in BU SIR model. We applied the Adams-Bashforth predictor corrector method to the proposed model. Numerical simulations are presented to illustrate the benefit of introducing a fractional model.