A groundbreaking study, the BOHEMIA trial-Broad One Health Endectocide-based Malaria Intervention in Africa- , has provided compelling evidence that mass drug administration (MDA) of ivermectin significantly reduces malaria transmission, offering new hope in the global fight against the disease.
The research, published in The New England Journal of Medicine, was coordinated by the Barcelona Institute for Global Health (ISGlobal) in collaboration with the Manhiça Health Research Centre (CISM) and the KEMRI-Wellcome Trust Research Programme.
Malaria continues to pose a significant global health challenge, with 263 million cases and 597,000 deaths reported in 2023. Current vector control methods, such as long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS), face diminishing effectiveness due to rising insecticide resistance and evolving mosquito behaviors. This necessitates the urgent development of innovative solutions to combat malaria.
Traditionally used to treat neglected tropical diseases like onchocerciasis (river blindness) and lymphatic filariasis (elephantiasis), ivermectin has demonstrated the ability to reduce malaria transmission by killing mosquitoes that feed on treated individuals.
Given the increasing resistance to conventional insecticides, ivermectin presents a promising new approach, particularly in regions where traditional methods are faltering.
The Unitaid-funded BOHEMIA project (Broad One Health Endectocide-based Malaria Intervention in Africa) conducted two MDA trials in high-burden malaria regions: Kwale County, Kenya, and Mopeia district, Mozambique.
The trials assessed the safety and efficacy of a single monthly dose of ivermectin (400 mcg/kg) administered for three consecutive months at the onset of the rainy season to reduce malaria transmission.
In Kenya, the intervention targeted children aged 5–15, while in Mozambique, it focused on children under five.
In Kwale County, Kenya, children who received ivermectin experienced a notable 26percent reduction in malaria infection incidence compared to those who received albendazole, the control drug.
The trial, involving over 20,000 participants and more than 56,000 treatments, revealed that ivermectin significantly lowered malaria infection rates, especially among children living further from cluster borders or in areas with more efficient drug distribution. The safety profile of ivermectin was favorable, with no severe drug-related adverse events and only mild, transient side effects consistent with its known profile.
“We are thrilled with these results,” stated Carlos Chaccour, co-principal investigator of the BOHEMIA project and an ISGlobal researcher at the time of the study, now a researcher at the Navarra Centre for International Development at the University of Navarra. “Ivermectin has shown great promise in reducing malaria transmission and could complement existing control measures. With continued research, ivermectin MDA could become an effective tool for malaria control and even contribute to elimination efforts.”
Joseph Mwangangi, from the KEMRI-Wellcome Trust Research Programme, added, “These results align with the World Health Organization’s (WHO) criteria for new vector control tools. The findings suggest that ivermectin MDA could be a valuable complementary strategy for malaria control, particularly where mosquito resistance to insecticides is a growing concern.” Marta Maia, BOHEMIA’s lead entomologist from the University of Oxford, echoed this sentiment.
The Mozambique trial in the rural district of Mopeia faced significant operational disruptions due to Cyclone Gombe (2022) and a subsequent cholera outbreak. Francisco Saúte, director of the Manhiça Health Research Centre (CISM), emphasized a crucial lesson learned: “One of the most important lessons we learned from the trial in Mopeia is that strong community engagement is essential. Building trust with local communities and fostering close collaboration with the Health Ministry, National Malaria Control Program, and local authorities was key to ensuring acceptance of the ivermectin MDA.
Beyond its impact on malaria, ivermectin MDA demonstrated significant collateral benefits. The BOHEMIA team observed a substantial reduction in the prevalence of skin infestations such as scabies and head lice in the ivermectin group in Mozambique.
Additionally, communities in Kenya reported a major reduction in bed bugs. These broader public health benefits underscore the value of integrating ivermectin into existing delivery systems.
This research is part of a larger global effort to assess ivermectin’s potential in malaria control. The WHO vector control advisory group has reviewed the findings, acknowledging the demonstrated impact and recommending further studies.
The results have also been shared with national health authorities as they evaluate the potential inclusion of ivermectin in malaria control programs.
Regina Rabinovich, BOHEMIA PI and Director of ISGlobal’s Malaria Elimination Initiative, concluded, “This research has the potential to shape the future of malaria prevention, particularly in endemic areas where existing tools are failing. With its novel mechanism of action and proven safety profile, ivermectin could offer a new approach using a well-known, safe drug that can add to the effect of other mosquito control tools available today.”
