On the transmission dynamics of Buruli ulcer in Ghana: Insights through a mathematical model

BMC Research Notes

Ebenezer Bonyah¹  Farai Nyabadza² 

[1] Department of Mathematics and Statistics, Kumasi Polytechnic, Kumasi, Ghana;Department of Mathematical Sciences, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa

关键词: Stability;    Sensitivity analysis;    Basic reproduction number;    Transmission dynamics;    Buruli ulcer;   

Others  :  1232738
DOI  :  10.1186/s13104-015-1619-5

 received in 2015-05-20, accepted in 2015-10-26,  发布年份 2015

【 摘 要 】

Background

Mycobacterium ulcerans is know to cause the Buruli ulcer. The association between the ulcer and environmental exposure has been documented. However, the epidemiology of the ulcer is not well understood. A hypothesised transmission involves humans being bitten by the water bugs that prey on mollusks, snails and young fishes.

Methods

In this paper, a model for the transmission of Mycobacterium ulcerans to humans in the presence of a preventive strategy is proposed and analysed. The model equilibria are determined and conditions for the existence of the equilibria established. The model analysis is carried out in terms of the reproduction number View MathML">. The disease free equilibrium is found to be locally asymptotically stable for View MathML"> The model is fitted to data from Ghana.

Results

The model is found to exhibit a backwardbifurcation and the endemic equilibrium point is globally stable when View MathML"> Sensitivity analysis showed that the Buruli ulcer epidemic is highly influenced by the shedding and clearance rates of Mycobacterium ulcerans in the environment. The model is found to fit reasonably well to data from Ghana and projections on the future of the Buruli ulcer epidemic are also made.

Conclusions

The model reasonably fitted data from Ghana. The fitting process showed data that appeared to have reached a steady state and projections showed that the epidemic levels will remain the same for the projected time. The implications of the results to policy and future management of the disease are discussed.

【 授权许可】

   
2015 Nyabadza and Bonyah.

【 图 表 】

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