Study design and participants
malaria, diarrhoea, allergy, vomiting
MALARIA, ALLERGY
We conducted an open-label, individually randomised controlled trial to compare the efficacy of malaria chemoprophylaxis with artemether–lumefantrine versus multivitamin among forest goers at 15 villages in Siem Pang District, Stung Treng province in northeastern Cambodia along the border with southern Laos. The selected district had the highest malaria incidences in Cambodia during 2018–19 at 142·3 cases per 1000 population in 2018 and 86·5 in 2019, and has high forest cover.Enrolment was between March 11 and Nov 20, 2020, with follow-up until Feb 17, 2021. Participants aged 16–65 years who planned to travel to the forest within the next 72 h and stay overnight, and who were willing and able to comply with the study protocol, were included in the study. Excluded from enrolment were women with known pregnancy or breastfeeding or who planned to become pregnant; individuals who had received ACT within the previous 7 days; individuals with a history of allergy or known contraindication to artemisinins, lumefantrine, or multivitamins; individuals with a documented or claimed history of cardiac conduction problems; individuals with severe vomiting or diarrhoea; and individuals with clinical malaria confirmed by an RDT.Before enrolment, written informed consent was obtained from participants, who received a copy of the signed consent form. For those who could not read or write Khmer, a fingerprint was obtained and countersigned by an impartial witness. For participants aged 16–18 years, written informed assent was also obtained.The trial was approved by the Cambodian National Health Research Ethics Committee (reference NECHR316), and by the University of Oxford Tropical Research Ethics Committee (reference 23-19). The study protocol has been published.