Abstract:
Cholera is a gastrointestinal disease caused by a bacterium called Vibrio cholerae.
The spread of the disease depends largely on social and environmental factors
such as, eating food or drinking water contaminated with feaces from an infected
person. Cholera outbreaks, for instance, in Kenya have led to deaths and hospi-
talisation. Since cholera spreads and kills very fast, the effectiveness of control
strategies such as vaccination, water chlorination and therapeutic treatment may
be enhanced by the use of media alert and awareness campaigns. This aspect has
not been considered in existing cholera models. In this study, the impact of media
coverage on the spread of cholera was investigated using a mathematical model.
The specific objectives of the study were to construct a mathematical model for
cholera transmission incorporating media coverage, to analyse the stability of equi-
librium points of the model and to evaluate the role of media coverage as a disease
control strategy. Positivity and boundedness of solutions was established to ensure
that the model was biologically meaningful. The model was thereafter analysed
using the stability theory of differential equations. The basic reproduction num-
ber R 0 , was derived using the next generation matrix approach. The existence of
equilibrium points of the model was determined. The results of stability analysis
showed that the disease free equilibrium was both locally and globally asymptoti-
cally stable when R 0 < 1 while the endemic equilibrium was locally asymptotically
stable when R 0 > 1. Simulation analysis done using existing epidemiological data
graphically confirmed the validity of the analytic results. The simulation results
also showed that when media coverage was efficient (ρ = 0.9, where 0 < ρ < 1
measures the efficacy of media coverage) the number of cholera infectives decreased
faster, while inefficient media reporting (ρ = 0.4) on an outbreak and the preven-
tive measures led to increased cases of infection, implying that, media alert and
awareness campaigns are vital in controlling the spread of cholera. Based on this
study, it is recommended that health practictioners embrace the use of efficacious
means of media coverage to publicise awareness campaigns of an outbreak and the
preventive measures.
