Abstract Introduction: Malaria remains a critical health challenge in Kenya, particularly among children under five years who are highly vulnerable to its complications. Artemisinin-based combination therapies (ACTs) are the recommended first-line treatment for uncomplicated malaria. However, their uptake varies due to socio-economic inequalities, geographic disparities, and the influence of social networks. Understanding how social interactions, particularly those mediated by religious affiliations, impact ACT uptake can inform strategies to improve malaria treatment outcomes in malaria-prone regions. Methods: This study utilized data from the Kenya Malaria Indicator Survey (KMIS) 2020, employing a cross-sectional design and stratified two-stage cluster sampling. Data on malaria prevalence, treatment-seeking behavior, and ACT usage were analyzed using descriptive statistics and logistic regression. The analysis focused on socio-demographic factors, geographic differences, and the role of social networks mediated through religious affiliations. Results: ACT uptake among children under five was 52%. Male children were less likely to receive ACTs, with probabilities 6.3% lower in rural areas and 3.1% lower in urban areas. Younger children in rural areas, particularly those aged one, had a 5.7% higher likelihood of ACT usage, while uptake declined with age. Caregivers' education significantly enhanced ACT uptake in rural areas, increasing the likelihood by 25%. Rural Muslim households were 17.2% more likely to use ACTs, while urban Christian households showed modest improvements. Wealth disparities also affected uptake, with wealthier urban households less likely to use ACTs. Conclusion: The study highlights the critical role of social networks, particularly religious affiliations, in shaping ACT uptake in malaria-prone zones of Kenya. Addressing barriers to access through these networks offers a promising avenue for increasing ACT utilization and improving health outcomes. Leveraging community-driven approaches and religious institutions could enhance equitable malaria treatment coverage across vulnerable populations. Keywords: Artemisinin-based Combination Therapy (ACT), Malaria treatment in under-five, Social networks, Religious affiliations

The authors have declared no competing interest.

This study did not receive any funding

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Kenya Malaria Indicator Survey (KMIS) 2020 was reviewed and approved by an ethics committee accredited by the National Commission for Science, Technology and Innovation (NACOSTI). The institutional review board (IRB) that reviewed KMIS 2020 study was the Kenyatta National Hospital Ethics and Research Committee (KNH-ERC). The reference number or ID for ethics approval is not in public domain but a request has been made to the Kenya National Bureau of Statistics (KNBS) to be shared when available. Data available at https://statistics.knbs.or.ke/nada/index.php/catalog/111

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