Mathematical Modeling of Cholera Transmission Dynamics with Vaccination and Pathogen Mutation: Model Development, Equilibrium Analysis and Basic Reproduction Number

Source abstract

Cholera is a disease caused by the bacterium Vibrio cholerae which is transmitted through contaminated water and food sources mainly in poorly sanitised areas. Cholera continues to pose a significant public health challenge in Kenya, with recurrent outbreaks complicating control measures such as the introduction of vaccination and sanitisation campaigns. Although there have been successful oral cholera vaccination programmes in controlling transmission, factors such as waning immunity, low vaccination levels and mutation of pathogens continue to threaten the eradication of the disease. Emergence of mutant strains that limit the efficiency of the vaccine poses a serious problem in the control of the disease and calls for a deeper study on the relationship between the vaccine and mutation of the disease. A deterministic compartmental model for describing the transmission dynamics of cholera with vaccination, pathogen mutation, environmental contamination, sanitization intervention and compliance with good hygiene practices was formulated in this study. The population in the study was separated into susceptible, vaccinated, wild-type infected, mutant infected and recovered compartments together with an environment bacteria compartment. Direct and environmental transmission, waning immunity, bacteria shedding, sanitization process and bi-directional mutation between the wild-type and the mutants were included in the model. T