Resistance of P.falciparum malaria parasites to the artemisinin derivatives in South East Asia is a direct threat to malaria control worldwide. But the rapid elimination of the parasite is possible.
The Malaria Elimination Task Force (METF) programme started in May 2014 in Karen State (Eastern Myanmar). The project’s objective is to eliminate multi-drug resistant P. falciparum from five townships bordering Thailand. This is a response to the threat presented by the emergence and spread of artemisinin resistance in P. falciparum and subsequent ACT failures. The results have been spectacular and as of to date, 83.6% of the 1,205 villages included in the programme in 2019, are below the elimination threshold as defined by the WHO and 83.5% of the villages reported zero P. falciparum clinical case in 2019. In the most remote part of Karen State, the yearly incidence of P. falciparum has reduced by 93.8% between 2014 and 2019. Given the rate of decline in P. falciparum cases, the programme is on track to achieve elimination by December 2020.
This is explained by the high community participation, the commitment of the partners, the impact of the malaria posts (MPs), the elimination of sub-microscopic reservoirs by mass drug administration (MDA) and perhaps to a certain extend by the mass distribution of long-lasting impregnated nets (LLINs). The real time reporting system has enabled rapid case investigations as well as the detection of non-functioning MPs and difficulties in the supply chain of rapid diagnostic tests (RDTs) and artemisinin combination treatments (ACT) to MPs, allowing for a fast response to problems encountered. During the course of this programme, some essential evidence has been gathered, analysed and shared with the partners and the National Programme.
The most important findings were published so they can be used by others. These findings relate to several key components of the elimination strategy: the impact of early detection and treatment, the accelerating impact of MDA, the importance of MP monitoring, and the crucial role of community engagement. Precious data on the bionomics of the local malaria vectors and alternative vector-control measures were also collected and analysed. It is therefore disappointing to see that none of these results are incorporated in the latest WHO supported National Malaria Control Strategic Plan of Myanmar. Importantly, the rapid elimination of P. falciparum from this area, has not translated so far into a worsening of drug resistance or into malaria resurgence or epidemics.
In 2020 we will have to complete the elimination of P. falciparum in the residual foci of transmission and develop a method to prove elimination. The absence of clinical cases does not demonstrate elimination, because some parasites can persist without symptoms for months or even years. METF will also concentrate on the elimination of P. vivax in this region. The strategy is likely to be different from that of P. falciparum elimination, due to the dormant liver stages of P. vivax. For this reason, the two species should not be pooled when reporting malaria cases, in the context of elimination. The elimination of P. vivax will involve the use of amino-8-quinoline drugs such as primaquine and/or tafenoquine. However, the use of these drugs implies the detection of G6PD deficiency as recommended by the WHO, to avoid potentially severe haemolysis in G6PD deficient individuals. In practice, METF will conduct Operational Research on the use of point of care testing of G6PD using rapid tests and biosensors, in order to administer these medicines safely.
Another on-going project is looking at the usefulness of remote sensing imaging to localize areas at risk of malaria transmission and re-introduction. This work is conducted in collaboration with the French development agency, Institut de Recherche pour le développement (IRD). Finally, METF will integrate other health projects in the same areas, related to maternal and child health, tuberculosis and non-malaria fevers, in order to diversify and strengthen the already existed MP network.