Exploring influencing factors affecting preventive behaviours of Plasmodium knowlesi malaria among at-risk communities: an application of the nominal group technique

Malaria remains a major public health issue in Southeast Asia, with Plasmodium knowlesi (P. knowlesi) emerging as a growing threat. Despite intensified prevention and control efforts, populations in this region remain highly vulnerable to this zoonotic disease, driven by the complex interactions between primates, mosquitoes, and humans. This study aims to explore understanding of the factors affecting communities vulnerable to P. knowlesi malaria and their preventive behaviours, tailored to the local context.

A group of participants with substantial expertise and experience in malaria programme implementation and field operations were assembled. Utilizing the Nominal Group Technique (NGT), a validated and systematic approach for facilitating group discussions aimed at consensus, we identified the essential points to prioritize factors affecting at-risk communities and their malaria prevention behaviours. NGT were conducted through virtual platforms in October 2024, achieving consensus when 80% of the experts concurred on specific ideas. Final rankings were established based on descending acceptance percentages.

Of the 21 items presented for voting, 20 were retained for final ranking, demonstrating a strong panel consensus on key factors influencing malaria risk and prevention behaviours. The voting response rate was 100%, and consensus was achieved in a single NGT round. The 20 selected items, endorsed by the expert panel, were categorized into four overarching themes: environmental risks, human-related risks, policy and organizational factors, and vector-related risks.

These findings provide a valuable foundation for refining malaria prevention strategies. Future research can leverage this consensus to deepen the understanding of malaria-prevention behaviours and enhance P. knowlesi malaria programs tailored to at-risk communities.