Factors associated with malaria transmission in children aged 3 to 59 months during seasonal malaria chemoprevention implementation, Kotido District, Uganda, 2024

Abstract

Introduction: Uganda introduced seasonal malaria chemoprevention (SMC) in the Karamoja region, an area where transmission of malaria is high. While SMC is effective in similar settings, 2023 surveillance data in Kotido District showed a 15% increase in malaria incidence among children during implementation. We investigated the factors driving transmission of malaria among children aged 3 to 59 months in Kotido and assessed SMC effectiveness. Methods: An unmatched 1:1 case-control study was conducted at three high-volume health facilities in Kotido in September 2024. Cases were children aged 3–59 months with parasitological’ confirmed malaria, while controls were children who tested negative for malaria at the same facilities, recruited concurrently. We conducted health facility exit interviews with caregivers of children to collect information on sociodemographic and clinical features. Logistic regression identified factors associated with malaria, and SMC effectiveness was computed as 1-adjusted odds ratio (aOR)*100. Results: We enrolled 272 cases and 272 controls. Most cases were female (141, 52%). More of the cases’ caregivers had a low malaria risk perception (64, 24%) compared to those of the controls (10, 4%). SMC provided a 94% (95% CI: 91%–96%) protection against malaria in children who took it within 28 days of the previous cycle. Children who had spent more than the recommended 28 days without SMC administration (adjusted odds ratio [aOR] = 17, 95%CI = 11–26), those with underlying medical conditions (aOR = 1.6, 95% CI = 1.02–2.5), and those whose caregivers had a low malaria risk perception (aOR = 5.0, 95% CI=2.3–11) were at a higher risk of getting malaria. Conclusion: Children who did not adhere to the 28-day SMC schedule, had existing health conditions, or whose caregivers perceived malaria as low risk had increased odds of contracting malaria. Strengthening adherence to SMC schedules, providing integrated care for children, and enhancing caregiver awareness could maximize SMC effectiveness and sustain malaria control efforts.