INTRODUCTION: Joint Base Charleston’s C-17 Globemaster III mission is executed by 400 active-duty members from three operational and support wings. Aircrew and mission-essential personnel travel to locations with endemic diseases which are mostly eradicated in the United States. Recently, two members contracted malaria after missions in Africa which required advanced hospital care. Personnel were provided chemoprophylaxis, but the members who contracted malaria were among several who chose not to take it. This preliminary survey assessed aircrew malaria prophylaxis adherence and examined potential factors contributing to nonadherence.METHODS: JB Charleston aircrew members who visited the Flight and Operational Medicine Clinic between January and April 2018 were administered a retrospective, online survey. Researchers performed descriptive statistics and Chi-squared analysis.RESULTS: Most respondents were pilots under 30 yr of age and were prescribed malaria chemoprophylaxis while on a mission. More than two-thirds of respondent aircrew members did not take the medication as prescribed or did not take it at all. Of those, over half of respondents stated too many pills/too many days and medication side effects as the main reasons for nonadherence. Furthermore, almost 70% of adherent members experienced negative medication side effects such as nausea and heightened dreams. There was no statistical relationship between crew position, age, side effects, and prophylaxis adherence.DISCUSSION: Numerous factors contribute to poor prophylaxis regimen compliance among aircrew members. This study highlighted the need for risk-based policy validation, improved patient education, prophylaxis enforcement, process improvements to facilitate adherence, and evaluation of perceived vs. actual risk.Rutherford AE, Yale RS, Finn MF. Malaria prophylaxis adherence among aircrew members. Aerosp Med Hum Perform. 2019; 90(7):643–646.