Unveiling the Hidden Threat: The Impact of Sub-Optimum Treatment on Acquired Immunity, Asymptomatic Cases, Malaria Dynamics

Malaria remains a persistent global health issue, despite ongoing control efforts such as anti-malarial drugs and insecticide-treated bed-nets, indoor residual spraying, etc.. The greatest impact of malaria, a mosquito-borne illness, is felt in Africa. This study develops a compartmental mathematical model focusing on the impact of sub-optimal treatment and asymptomatic carriers on malaria transmission. The model is parametrized with malaria data from Kenya. Further, simulations involving these parameters assess various options of addressing malaria. Results of the simulations show key model parameters, including mosquito biting rates and treatment-seeking behavior, significantly affect disease control. Global Sensitivity analysis highlighted the critical impact of successful identification and treatment of individuals who received sub-optimal care. A DALYs analysis from 2002-2020 revealed that symptomatic individuals initially dominated the disease burden, but by 2020, asymptomatic individuals contributed equally and eventually contributed more. This shift underscores the growing importance of addressing asymptomatic carriers in malaria control strategies. The findings align with observed policy changes in Kenya over the study period. The study highlights the critical need for targeting both symptomatic and asymptomatic individuals in malaria control efforts, emphasizing the importance of early treatment-seeking behavior and vector management for long-term disease reduction.