Modelling the Transmission Dynamics of Banana Xanthomonas Wilt Disease with Contaminated Soil

Abstract

Banana Xanthomonas Wilt disease (BXW) is a bacterial disease which highly threaten banana production in east and central Africa. It is caused by a bacteria known as Xanthomonas campestris pv. musacearum (Xcm). Mathematical modelling gives an insight on how to best understand the transmission dynamics and control of the disease. The existing mathematical models have not included contaminated soil in the dynamics of BXW. In this study we formulated a model which includes contaminated soil, calculated the basic reproduction number and carried out sensitivity analysis of some model parameters. We further conducted numerical simulation to validate the results. The simulations show that the infection rate by contaminated farming tools ( i b and e b ), the infection rate by contaminated soil ( 2 w ), vertical disease transmission rate (q ), and the shedding rate of Xcm bacteria in the soil (f ) are positively sensitive to the basic reproduction number. While, the most negative sensitive parameters are the clearance rate of Xcm bacteria from the soil ( h m ), removal of infected plants from the farm ( r ), harvesting ( p a ), and banana plants disease induced death rate ( d ).The result also shows that contaminated soil contributes to the transmission and persistence of BXW disease. Therefore, we recommend that, along with the existing control measures scientist and technologist should carry out studies to find a way to reduce or avoid vertical disease transmission and increase the Xcm clearance rate in the soil. Furthermore, technology for early detection of infected plants should be brought down to the local farmers at affordable costs. This will help stakeholders to detect and remove the infected plants from the farm in time and hence reduce the number of secondary infections.