Assessing the Impact of Optimized Prevention Strategies for Mother-To-Child HIV Transmission Dynamics in Kenya: A Mathematical Modeling Study

Human immunodeficiency virus (HIV) can be transmitted from a HIV-infected mother to her child during pregnancy, delivery, or breastfeeding. According to NSDCC 2025, Kenya has an estimated PMTCT coverage of 90.1% and a PMTCT transmission rate of 9.26%. Although strides have been made to address PMTCT, there is a need to scale up approaches in addressing MTCT in order to significantly advance elimination. This research formulates a mathematical model to represent the dynamics of MTCT. Equilibrium points of the model are computed, and the stability of the HIV-free point is investigated. Using the Kenyan data, the model has been calibrated to obtain parameters not available in the literature. Uncertainty and sensitivity analysis are performed using Latin hypercube sampling and partial rank correlation coefficients (LHS and PRCCs). The numerical results show that a 50% decrease in maternal HIV transmission lowers infant infection rates by about 9%, whereas the same reduction in infant transmission decreases infections by nearly 31%, highlighting the greater sensitivity of infant transmission rates to direct interventions. While a combination of strategies achieves the highest HIV minimization rates of up to 83.16% on infants, ART adherence alone significantly reduces transmission, particularly on infants (74.39%), while use of prophylaxis (PrEP and PEP) shows limited effectiveness when used alone (28.83%), suggesting that it should be complemented with other strategies for optimal impact. These results are scenario-based estimates and can be used as theoretical upper-bound projections in PMTCT. These findings emphasize the critical need for integrated interventions, where combining multiple prevention methods yields the best outcomes in reducing HIV infections in infants and moving closer to the elimination of pediatric HIV.