Community patient follow-up as a part of P. vivax case management in Cambodia: a mixed methods study

Community health workers are key to improving global health. In Cambodia, a malaria-endemic country, village malaria workers (VMWs) have helped reduce malaria over the last two decades. In 2021, VMWs were tasked to support health facility workers (HFWs) in conducting follow-up of patients with Plasmodium vivax malaria to ensure adherence to treatment and patient safety. The aim of this study was to assess and explore the implementation of VMW follow-up in Cambodia. Mixed methods were employed with a period of analysis between January 2021 and March 2023. Qualitative data were collected from policymakers, sub-national program officials, HFWs, VMWs, and patients. Patient-specific quantitative surveillance data were gathered from nine study sites and complemented with national aggregate data. A thematic analysis of the qualitative data was conducted, and key proportions were derived from quantitative data. All data were interpreted together with an interpretivist theoretical framework of implementation, combining existing frameworks’ components, such as expectation, coherence, adoption, and ‘doability’ (component of feasibility). Overall, 2,138 patients with P. vivax malaria received primaquine in 2021 and 2022, of whom 39% were followed up in 2021 and 88% in 2022; more than half of the follow-up happened at the community level. Qualitative data indicated that the way and extent to which follow-up was implemented varied depending on the strategies VMWs adopted to ensure that the intervention was ‘doable’. These strategies included flexibility on which days patients were visited and reaching patients through their families. VMWs aimed to achieve the intervention’s purpose as per the guidelines, which is to enhance adherence and treatment safety. They also sought to achieve additional value attributed to the intervention, including comforting patients or conducting health education. Follow-up visits were well embedded into VMWs’ role and responsibilities. This was supported by VMWs’ understanding of the intended purpose and added value they attributed to the intervention, as well as their adaptive implementation strategies to make the intervention ‘doable’. These strategies should be integrated into policy and existing infrastructure while encouraging and resourcing problem-solving grounded in formal guidelines and training to achieve the intervention’s intended purpose and added value.