The development and testing of tools to aid malaria elimination efforts is an important focus of the Department’s research. Even in areas with very low malaria transmission, ultrasensitive methods developed by our molecular laboratory show that the number of asymptomatic individuals carrying Plasmodium parasites is substantial. These parasites in asymptomatic carriers are essential for maintaining malaria endemicity in low-transmission areas such as SE Asia.
Early work from our modelling team showed that the only way to get rid of artemisinin-resistant falciparum malaria in a region is by eliminating all falciparum malaria (the ‘last man standing’ is the most resistant). This prediction was later confirmed by observations in the field, which showed that with a reduction in overall number of malaria infections the proportion of artemisinin resistant infections only increased. This has now been recognized by the malaria community, and a malaria elimination strategy for the region is now advocated.
Coordinated by Lorenz von Seidlein, our targeted malaria elimination (TME) studies aim to evaluate treatment of whole villages with high prevalence of malaria carriers. This targeted approach of a mass drug administration might become an important strategy for the elimination of malaria.
The TME study sites in Cambodia, Laos, Myanmar, Thailand and Viet Nam will each enrol around 2,000 subjects. The studies require profound community engagement, which is essential to facilitate the buy-in from villagers to contribute to the extensive surveys and to assure proper coverage of the mass drug administration in the intervention villages. The interventions effectiveness is carefully monitored over time through assessment of the malaria prevalence, including the asymptomatic carriers in the intervention compared to the control villages.
Our malaria laboratory evaluates drugs (primaquine, methylene blue and others) affecting gametocytes, the sexual stages responsible for transmission of the disease.
Our TME investigators include Lorenz von Seidlein, Nick White, Arjen Dondorp, Nick Day and Decha Tangseefa in Bangkok, François Nosten of SMRU on the Myanmar-Thai border; Dr. Chea Nguon, Rupam Tripura and Tom Peto at Pailin, Cambodia; Frank Smithuis in Myanmar; Profs Hien and Thanh Thuy Nhien in Viet Nam; and Mayfong Mayxay and Paul Newton in Laos.