Understanding the Dynamics of Amebiasis Using Mathematical Modelling Approach: Optimal Control Strategies and Cost-Effectiveness Analysis

Abstract

Amebiasis is a parasitic infection of the intestine caused by the amoeba Entamoeba histolytica, and it is endemic in tropical countries with poor sanitation and hygiene practices. To
explore the dynamics of amebiasis and identify effective control interventions, a mathematical
model is developed. This model incorporates a treatment class within the human population
and accounts for the concentration of the amebiasis pathogen in the environment. The study
derived the steady states, stability, and the basic reproduction number of the infection. A
global sensitivity analysis is also conducted to identify the most significant parameters influencing the disease’s spread. Subsequently, an optimal control model is formulated, featuring
four time-dependent controls: hygiene practices, efficient screening of infected individuals, effective treatment, and disinfection/sterilisation of the environment. This model is analysed
and simulated across four categories — single, double, triple, and quadruple combination cases
— to assess the impact of these control measures. Additionally, a cost-effectiveness analysis
is conducted using the incremental cost-effectiveness ratio (ICER) method. The findings offer valuable insights that can help policymakers effectively control the disease while managing
limited resources. The results indicate that any control combination that includes efficient
screening of infected individuals is the most cost-effective strategy for reducing amebiasis in society. However, in a single case where resources are limited, Strategy 2 - efficient screening of infected individuals - emerges as the most cost-effective method for eradicating the disease.
With additional resources, the most effective double-combined control strategy for disease eradication is Strategy 8, which combines Strategy 2 with efficient treatment. For the triple control strategy, the most cost-effective control Strategy is Strategy 14, which integrates Strategy 8 and disinfection/sterilisation of the environment. However, the overall most cost-effective strategy remains Strategy 2.