Monitoring of malaria drug resistance

Abstract

Drug resistance falciparum malaria is a major health problem in Thailand. To deal with this problem, monitoring of parasite drug susceptibility is the important process. The in vivo response is an important strategy to evaluate the efficacy of antimalarial drug, altogether with the in vitro test. There are many methods to perform the susceptibility test, the microscopic method is not suitable to do in field study due to many limitations such as laborious and time consuming method. Therefore the next development methods will get rid of this weak point. The radioisotope assays had been developed and allow performing susceptibility with several cases. How ever the major limitation of this method is using the radio-compound. Concerning the risk of using radio-compound, the next generation of susceptibility method is modifying by change to safety substance such as HRP2 or fluorescence. These new methods will be needed the validation of test results. The factors that might be affected the result are incubation time and the type of antimalarials. The previous report of drug resistance malaria along Thai borders showed a markedly of treatment failure from the present regimen (artesunate-mefloquine). The molecular basis of pfcrt, pfmdr1 and pfatp6 have been reported to correlate with treatment failure especially the increased copy number of pfmdr1. However, these data is controversial and need more evidences.