Compliance with Malaria Preventive Measures by U.S. Military Personnel Deployed in Support of Ebola Control Efforts in Liberia

Background: The U.S. Government deployed over 2500 military personnel to support ebola control efforts in Liberia, which has one of the highest malaria risks in the world.  Compliance with preventive measures among travelers to malarious areas is historically low, with military-specific compliance with chemoprophylaxis reported between 30-55% over the past decade of combat operations. We conducted a survey of military personnel deployed to Liberia to assess compliance with preventive measures in a high-risk malaria area.

Methods: Deployed U.S. service members completed a voluntary 25 question anonymous survey administered over a 4-week period. The survey included questions on demographic information, malaria prevention education prior to deployment, and adherence with preventive measures, such as use of DEET on exposed skin, permethrin-treated uniforms and bed nets, and malaria chemoprophylaxis.

Results: 1220 individuals (65% of total deployed force during the survey period) completed the survey, which was representative of the overall population, based on age, gender, military rank, and location.  Mean duration of deployment was 66 days, and 63% had received malaria chemoprophylaxis on previous deployments.  99.3% reported receiving education on malaria prevention before leaving the U.S. 53% reported using DEET on most days, 91% reported using treated uniforms, 96% using bed nets, and 96% taking malaria chemoprophylaxis pills every day (98% received atovaquone-proguanil; 1.5% doxycycline).  No cases of malaria were detected during deployment. As part of mandated twice daily unit-level ebola monitoring (consisting of temperature checks and review of ebola exposures and symptoms), individuals were also asked about use of antimalarials. 45% of those surveyed indicated that their unit also directly observed them taking their antimalarial daily.

Conclusion: Adherence with preventive measures in a high-risk malaria area was among the highest ever observed among a deployed military force of this size. Pre-deployment education, daily unit monitoring while deployed, and the use of atovaquone-proguanil contributed to improved adherence. Similar large-scale monitoring programs may contribute to improved adherence and disease prevention for individuals and populations traveling to high-risk malaria areas.