Background It is acknowledged that Human Infection Studies (HIS) can accelerate discovery of promising therapies, but this particular research design presents significant ethical, social and cultural challenges, particularly on LMICs. Over the last eight years, embedded social science and ethics research on ongoing malaria HIS examine some of these contextually sensitive challenges. We conducted an embedded social science study in an ongoing malaria vaccine efficacy trial within a HIS in coastal Kenya to further document how experience of participation varied across different malaria HIS.

Methods We conducted 3 focus group discussions and 20 interviews, with 38 male and female HIS participants after vaccination, and during residency, between October 2022 and February 2023. Voice recordings were transcribed, translated, and analyzed using thematic analysis.

Results HIS volunteers reported a range of previous benefits and burdens of study participation. In general [during the in-patient stay], there was raised anxiety around COVID-19 testing, where positivity was an exclusion criteria, considering the need to observe and mitigate for prevention measures such as physical distancing and exit from study participation. Although weekly payments were preferred, their disbursement had logistical and administrative delays and requirements that resulted in strained relationships between participants, family members and the study team. Similar to previous studies participants appreciated using funds from the financial compensation for immediate household needs during the in-patient stay, access to medical screening and general care during in-patient stay.

Conclusion In this preliminary analysis, we highlight the need for HIS teams to carefully consider, striking a balance between potential burdens vs benefits, in the design and conduct of studies, while also being proactive in documenting and responding to unanticipated issues emerging during the study that could affect study participants wellbeing.