The global scale-up of vector control and improved case management has helped bring malaria cases and deaths to record lows since 2000. Endemic countries and donors are now working toward a world without malaria. Since 2010, PATH, through the Malaria Control and Elimination Partnership in Africa (MACEPA), has been investigating ways to accelerate this process by using drugs to clear parasites from their human hosts. If these approaches, known as population-wide drug-based strategies, are effective, feasible, and affordable, they may reduce malaria transmission in the short term to a level where it could be eliminated through strong surveillance that allows for tracking and treating each case.
This week, PATH released a brief on findings from this research as the first installment of their new Malaria Learning Series. The Learning Series is a suite of reports on current topics in malaria science that will provide practitioners, policymakers, and donors with the most recent evidence for decision-making. Topics will include emerging tools and strategies, health system and surveillance innovations, and planning for elimination.
The first report in the series, Population-Wide Drug-Based Strategies for Malaria Elimination, showcases and compares research being conducted by PATH and its partners in three African countries across a range of transmission intensities. The data-driven approach to malaria elimination and lessons learned documented in the report go beyond standard program evaluation. Instead of evaluating individual malaria programs and slowly ticking off those that don’t work, PATH is building evidence on elimination theory by combining different population-wide drug-based strategies with standard vector control measures; working toward advancing guidance and tools for malaria elimination.
One of the population-wide drug-based strategies highlighted in the report is mass drug administration (MDA), a public health tool used since the 1930s with varying success against malaria, schistosomiasis, soil-transmitted parasites, and other diseases. MDA involves treating everyone in a targeted geographic area (excluding those who may have contraindications to receiving the drug), whether they have the disease or not. Not everyone with malaria appears ill, so mass treatment ensures that those with infections that are asymptomatic or not able to be detected by usual diagnostic tests are treated, killing enough parasites to reduce transmission substantially. The approach had mixed success when used in earlier eras of the malaria fight, but may achieve more durable results when used in a time-limited and strategic way with other interventions to fight malaria.
The report discusses findings from a study in Zambia, and found that MDA was operationally feasible across large areas, leveraging existing community health worker networks and surveillance systems to achieve high coverage. Other strategies discussed in the report, such as mass test and treat—where the whole population is tested with a rapid diagnostic test (RDT) and with only positive individuals treated—resulted in only a modest impact on malaria case incidence, likely because of the imperfect sensitivity of the diagnostic used for screening.
Over the past three years, PATH, in partnership with the national malaria control programs in Zambia, Ethiopia, and Senegal, has conducted research to study the potential for these strategies to accelerate elimination. By working across three countries, PATH hopes to better understand the potential role of population-wide drug-based strategies as an elimination accelerator when combined with the right suite of supporting interventions. This research could contribute to future guidance for countries aspiring to eliminate malaria, bringing them a step closer to a healthier future.