Efficacy of chloroquine, chloroquine plus sulphadoxine-pyrimethamine, and amodiaquine for treatment of vivax malaria in Bangka island, Indonesia: a randomized trial.

Plasmodium vivax malaria resistant to chloroquine is alarming in Indonesia and has been also reported in other countries. An alternative drug is needed. The study was a prospective evaluation and a comparative study of the therapeutic efficacy of chloroquine 25 mg base/kg bw for 3 days (CQ3, n=75), CQ3 plus sulfadoxine-pyrimethamine based on pyrimethamine dosage of 1.25 mg/kg bw single dose (SP1) [CQ3+SP1, n=84] and amodiaquine 25 mg base/kg bw for 3 days (AQ3, n=83) in symptomatic vivax malaria patients in children and adults. The new version of 2001 WHO test system was used in this study. PCR for genotyping was also done to validate and confirm the treatment outcomes. The therapeutic efficacy of CQ3, CQ3+SP1 and AQ3 on day 14 were very high (94.4%, 97.4% and 98.8%), and dropped on day 28 (81.7%, 87.2% and 96.2% by evaluable analysis; 78.9%. 82.0% and 92.5% after confirmation with PCR; and 74.7%, 78.0% and 90.2% by intention to treat analysis). Most of the ACPR cases (>96%) showed hematological recovery. Gametocyte carriages were documented on day 7 (2.9%, 1.3% and 1.2%), day 14 (4.3%, 1.3% and 1.2%) and day 28 (6.6%, 4.2% and none) in CQ3, CQ3+SP1 and AQ3 groups. Of these 3 regimens, AQ3 showed a better therapeutic efficacy than CQ3 and combined CQ3+SP1 by day 28. Introducing primaquine at the beginning of treatment day or giving a radical treatment in vivax malaria may improve the cure rate.

Mekong malaria. II. Update of malaria, multi-drug resistance and economic development in the Mekong region of Southeast Asia.

In an expansion of the first Mekong Malaria monograph published in 1999, this second monograph updates the malaria database in the countries comprising the Mekong region of Southeast Asia. The update adds another 3 years' information to cover cumulative data from the 6 Mekong countries (Cambodia, China/Yunnan, Lao PDR, Myanmar, Thailand, Viet Nam) for the six-year period 1999-2001. The objective is to generate a more comprehensive regional perspective in what is a global epicenter of drug resistant falciparum malaria, in order to improve malaria control on a regional basis in the context of social and economic change. The further application of geographical information systems (GIS) to the analysis has underscored the overall asymmetry of disease patterns in the region, with increased emphasis on population mobility in disease spread. Of great importance is the continuing expansion of resistance of P. falciparum to antimalarial drugs in common use and the increasing employment of differing drug combinations as a result. The variation in drug policy among the 6 countries still represents a major obstacle to the institution of region-wide restrictions on drug misuse. An important step forward has been the establishment of 36 sentinel sites throughout the 6 countries, with the objective of standardizing the drug monitoring process; while not all sentinel sites are fully operational yet, the initial implementation has already given encouraging results in relation to disease monitoring. Some decreases in malaria mortality have been recorded. The disease patterns delineated by GIS are particularly instructive when focused on inter-country distribution, which is where more local collaborative effort can be made to rationalize resource utilization and policy development. Placing disease data in the context of socio-economic trends within and between countries serves to further identify the needs and the potential for placing emphasis on resource rationalization on a regional basis. Despite the difficulties, the 6-year time frame represented in this monograph gives confidence that the now well established collaboration is becoming a major factor in improving malaria control on a regional basis and hopefully redressing to a substantial degree the key problem of spread of drug resistance regionally and eventually globally.