Randomized controlled trials of 5- and 14-days primaquine therapy against relapses of vivax malaria in an Afghan refugee settlement in Pakistan
✍ Scribed by Mark Rowland; Naeem Durrani
- Publisher
- Elsevier Science
- Year
- 1999
- Tongue
- English
- Weight
- 443 KB
- Volume
- 93
- Category
- Article
- ISSN
- 0035-9203
No coin nor oath required. For personal study only.
✦ Synopsis
Primaquine is the only drug available that can eliminate hypnozoites from the liver and prevent relapses of vivax malaria. The World Health Organization recommends a course of 14-21 days depending on region and strain. The National Malaria Control and Eradication Programmes of Pakistan and India have adhered to a 5-day course as their standard as it is deemed more practical to implement and because facility for detecting glucose 6-phosphate dehydrogenase (GGPD) deficiency is seldom available at the periphery. Evidence for the effcacv of the 5-dav regimen is controversial or lackinn. Two. vear-long. randomized controlled trials were undertaken in ah Afghan refugee camp in north-western Pakistan usirg a process of passive case detection and treatment at the camp's clinic: the first trial compared treatment with chloroquine alone versus chloroquine plus 5-days primaquine, the second trial compared chloroquine alone versus chloroquine plus 14-days primaquine. Chloroquine is not hypnozoitocidal and was administered to eliminate the erythrocytic stages and to alleviate clinical symptoms. The daily primaquine dose was 0.25 mg/kg bodyweight and the total chloroquine dose was 25 mg/kg over 3 days. During the first trial 52% (1291250) of the non-primaquine group recorded a 2nd clinical-parasitaemic episode and 23% recorded a 3rd, whereas 5 1% (128/250) of the 5-days primaquine group reported a 2nd episode and 21% recorded a 3rd. During the second trial 49% (49/100) of the non-primaquine group recorded a 2nd episode and 25% recorded a 3rd, whereas only 32% (32/100) of the 14-days primaquine group recorded a 2nd and only 2% recorded a 3rd. The 5-days primaquine regimen has no value as an anti-relapse therapy and should be abandoned. In extended tests in vivo in which vivax cases (n = 3 1) were treated with chloroquine 25 mg/kg and 14-days primaquine, there was no parasite recrudescence within 28 days and hence no evidence of resistance to chloroquine.