Volume 75, Issue 1
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


This study investigated the association between chloroquine resistance transporter () and multidrug resistance gene 1 () alleles and amodiaquine (AQ) resistance, as well as the clearance of parasites harboring these two alleles in children treated with AQ in southwest Nigeria. One hundred one children with acute uncomplicated malaria infections were treated with the standard dosage of AQ and followed-up for 28 days. Blood samples were collected on filter paper samples at enrollment and during follow-up for identification of parasite genotypes and and mutations using polymerase chain reaction and restriction fragment length polymorphism approaches. Parasitologic assessment of response to treatment showed that 87% and 13% (RI) of patients were cured and failed treatment, respectively. Although infections in patients were polyclonal (as determined by merozoite surface protein 2 genotyping), the presence of both mutants and alleles in parasites is associated with AQ resistance (odds ratio = 7.58, 95% confidence interval = 1.58–36.25, = 0.006) and is selected by the drug in children who failed AQ treatment. Treatment failure with the combination of mutant and alleles as well as the ability of patients to clear these resistant parasites is dependent on age, suggesting a critical role of host immunity in clearing AQ-resistant . The combination of mutant and alleles may be useful markers for monitoring the development and spread of AQ resistance, when combining this drug with other antimalarials for treatment of malaria in Africa.


Article metrics loading...

The graphs shown below represent data from March 2017
Loading full text...

Full text loading...



  1. Trape JF, Pison G, Preziosi MP, Enel C, Desgrees du Loup A, Delauney V, Samba B, Lagarde E, Molez JF, Simondon F, 1998. Impact of chloroquine resistance on malaria mortality. CR Acad Sci III 321 : 689–697. [Google Scholar]
  2. Trape JF, 2001. The public health impact of chloroquine resistance in Africa. Am J Trop Med Hyg 64 : 12–17. [Google Scholar]
  3. WHO, 2001. Antimalarial Drugs Combination Therapy. Report of a WHO Technical Consultation. Geneva: World Health Organization. WHO/RCS/RBM/2001.35.
  4. Adjuik M, Agnamey P, Babiker A, Borrmann S, Brasseur P, Cisse M, Cobelens F, Diallo S, Faucher JF, Garner P, Gikunda S, Kremsner PG, Krishna S, Lell B, Loolpapit M, Matsiegui PB, Missinou MA, Mwanza J, Ntoumi F, Olliaro P, Osimbo P, Rezbach P, Some E, Taylor WR, 2002. Amodiaquine-artesunate versus amodiaquine for uncomplicated Plasmodium falciparum malaria in African children: a randomized, multicentre trial. Lancet 359 : 1365–1372. [Google Scholar]
  5. Meshnick SR, Alker AP, 2005. Amodiaquine and combination chemotherapy for malaria. Am J Trop Med Hyg 73 : 821–823. [Google Scholar]
  6. Childs GE, Boudreau EF, Milhous WK, Wimonwattratee T, Pooyindee N, Pang L, Davidson DE Jr, 1989. A comparison of the in vitro activities of amodiaquine and desethylamodiaquine against isolates of Plasmodium falciparum. Am J Trop Med Hyg 40 : 7–11. [Google Scholar]
  7. Basco LK, Le Bras J, 1993. In vitro activity of monodesethyla-modiaquine and amopyroquine against African isolates and clones of Plasmodium falciparum. Am J Trop Med Hyg 48 : 120–125. [Google Scholar]
  8. Sowunmi A, Salako LA, 1992. Evaluation of the relative efficacy of various antimalarial drugs in Nigerian children under five years of age suffering from acute uncomplicated falciparum malaria. Ann Trop Med Parasitol 86 : 1–8. [Google Scholar]
  9. Bloland PB, Ruebush TK, 1996. Amodiaquine. Lancet 348 : 1659–1660. [Google Scholar]
  10. White NJ, 1996. Can amodiaquine be resurrected? Lancet 348 : 1184–1185. [Google Scholar]
  11. Sowunmi A, Ayede AI, Falade AG, Ndikum VN, Falade CO, Happi TC, Oduola AMJ, 2001. Randomized trials of chloroquine and amodiaquine in acute uncomplicated Plasmodium falciparum malaria in children. Ann Trop Med Parasitol 95 : 549–558. [Google Scholar]
  12. Schellenberg D, Kahigwa E, Drakeley C, Malende A, Wigayi J, Msokame C, Aponte JJ, Tanner M, Mshinda H, Menendez C, Alonso PL, 2002. The safety and efficacy of sulfadoxine-pyrimethamine, amodiaquine, and their combination in the treatment of uncomplicated Plasmodium falciparum malaria. Am J Trop Med Hyg 67 : 17–23. [Google Scholar]
  13. Ginsburg H, Famin O, Zhang J, Krugliak M, 1998. Inhibition of glutathione-dependent degradation of heme by chloroquine and amodiaquine as possible basis for their antimalarial mode of action. Biochem Pharmacol 56 : 1305–1313. [Google Scholar]
  14. Bray PG, Mungthin M, Ridley RG, Ward SA, 1998. Access to hematin: the basis of CQ resistance. Mol Pharmacol 54 : 170–179. [Google Scholar]
  15. Foote SJ, Kyle DE, Martin RK, Oduola AM, Forsyth K, Kemp DJ, Cowman AF, 1990. Several alleles of the multidrug-resistance genes are closely linked to chloroquine resistance in Plasmodium falciparum. Nature 345 : 255–258. [Google Scholar]
  16. Frean JA, El-Kariem FM, Warhurst D, Milles M, 1992. Rapid detection of pfmdr1 mutations in chloroquine resistant Plasmodium falciparum malaria by polymerase chain reaction analysis of blood spot resistant. Trans R Soc Trop Med Hyg 86 : 29–30. [Google Scholar]
  17. Adagu IS, Warhurst DC, Carruci DJ, Duraisingh MT, 1995. Pfmdr1 mutations and chloroquine-resistance in Plasmodium falciparum isolates from Zaria, Nigeria. Trans R Soc Trop Med Hyg 89 : 132. [Google Scholar]
  18. Basco LK, De Poucelas PE, Le Bras J, Wilson CM, 1996. Plasmodium falciparum: molecular characterization of multidrug-resistant Cambodian isolates. Exp Parasitol 82 : 97–103. [Google Scholar]
  19. Duraisingh MI, Drakeley CI, Muller O, Bailey R, Snounou G, Targett GA, Greenwood B, Warhurst D, 1997. Evidence for selection for the tyrosine 86 allele of pfmdr1 gene of Plasmodium falciparum by chloroquine and amodiaquine. Parasitology 114 : 205–211. [Google Scholar]
  20. Fidock DA, Takashi N, Talley AK, Cooper RA, Dzekunov SM, Ferdig MT, Ursos LMB, Sidhu AB, Naude B, Kirk WD, Su X-Z, Wootton JC, Roepe PD, Wellems TE, 2000. Mutation in the P. falciparum digestive vacuole transmembrane protein Pfcrt and evidence for their role in chloroquine resistance. Mol Cell 6 : 861–871. [Google Scholar]
  21. Reed MB, Saliba KJ, Caruana SR, Kirk K, Cowman AF, 2000. Pgh1 modulates sensitivity and resistance to multiple antimalarials in Plasmodium falciparum. Nature 403 : 906–909. [Google Scholar]
  22. Durand R, Jafari S, Vauzelle J, Delabre JF, Zorica J, Le bras J, 2001. Analysis of pfcrt point mutations and chloroquine susceptibility in Isolates of Plasmodium falciparum. Mol Biochem Parasitol 114 : 95–102. [Google Scholar]
  23. Adagu I, Dias FP, Rombo L, Do Rosario V, Warhurst D, 1996. Guinea Bissau: association of chloroquine resistance of Plasmodium falciparum with the Tyr86 allele of the multiple drug resistance gene. Trans R Soc Trop Med Hyg 90 : 90–91. [Google Scholar]
  24. Basco LK, Ringwald P, 1998. Molecular epidemiology of malaria in Yaounde, Cameroon. III. Analysis of chloroquine resistance and point mutations in the multidrug resistance 1 (pfmr1) gene of Plasmodium falciparum. Am J Trop Med Hyg 59 : 577–581. [Google Scholar]
  25. Djimde A, Doumbo OK, Cortese JF, Kayentao K, Doumbo S, Diourte Y, Dicko A, Su X-Z, Noruma T, Fidock DA, Wellems TE, Plowe CV, 2001. A molecular marker for chloroquine-resistant falciparum malaria. N Engl J Med 344 : 257–263. [Google Scholar]
  26. Warhurst D, 2001. A molecular marker for chloroquine-resistant falciparum malaria. N Engl J Med 344 : 299–302. [Google Scholar]
  27. Dylan RP, Labbe AC, Vaniasaveth V, Hongvangthong B, Pomphida S, Souliya I, Zhong K, Kain KC, 2001. Plasmodium falciparum malaria in Laos: chloroqine treatment outcome and predictive value of molecular markers. J Infect Dis 183 : 789–795. [Google Scholar]
  28. Babiker HA, Pringle SJ, Abdel-Mushin A, Mackinnon P, Hunt P, Walliker D, 2001. High-Level chloroquine resistance in Sudanese isolates of Plasmodium falciparum is associated with mutations in the chloroquine resistance transporter gene pfcrt and the multidrug-resistance gene pfmdr1. J Infect Dis 183 : 1535–1538. [Google Scholar]
  29. Dorsey G, Kamya MR, Singh A, Rosenthal P, 2001. Polymorphisms in the Plasmodium falciparum pfcrt and pfmdr1 genes and clinical response to chloroquine in Kampala, Uganda. J Infect Dis 183 : 1417–1420. [Google Scholar]
  30. Maguire JD, Susanti AI, Krisin MH, Sismadi P, Fryauff DJ, Baird JK, 2001. The 76 mutation in the pfcrt gene of Plasmodium falciparum and clinical chloroquine resistance phenotype in Papua, Indonesia. Ann Trop Med Parasitol 95 : 559–562. [Google Scholar]
  31. Omar SA, Adagu IS, Gump DW, Ndaru NP, Warhurst DC, 2001. Plasmodium falciparum in Kenya: high prevalence of drug-resistance-associated polymorphisms in hospital admissions with severe malaria in an epidemic area. Ann Trop Med Parasitol 95 : 661–669. [Google Scholar]
  32. Happi TC, Gbotosho GO, Falade CO, Akinboye DO, Gerena L, Hudson T, Sowunmi A, Kyle DE, Milhous W, Wirth DF, Oduola AMJ, 2003. Point mutations in the pfcrt and pfmdr-1 genes of Plasmodium falciparum and clinical response to chloroquine among malaria patients from Nigeria. Ann Trop Med Parasitol 97 : 439–451. [Google Scholar]
  33. Happi CT, Gbotosho GO, Sowunmi A, Falade CO, Akinboye DO, Hudson T, Gerena L, Kyle DE, Milhous W, Wirth DF, Oduola AMJ, 2004. Molecular analysis of Plasmodium falciparum recrudescent malaria infections in children treated with chloroquine in Nigeria. Am J Trop Med Hyg 70 : 20–26. [Google Scholar]
  34. Tinto H, Sanou B, Dujardin JC, Ouedraogo JB, VAN Overmeir C, Erhart A, VAN Marck E, Guiguemde TR, D’Alessandro U, 2005. Usefulness of the Plasmodium falciparum chloroquine resistance transporter T76 genotype failure index for the estimation of in vivo chloroquine resistance in Burkina Faso. Am J Trop Med Hyg 73 : 171–173. [Google Scholar]
  35. World Health Organization, 2000. Severe falciparum malaria. Trans R Soc Trop Med Hyg 94 (Suppl 1): S1–S90. [Google Scholar]
  36. WHO, 1996. Assessment of Therapeutic Efficacy of Antimalarial Drugs for Uncomplicated Malaria in Areas with Intense Transmission. Geneva: World Health Organization. WHO/MAL/96-1077.
  37. Happi CT, Gbotosho GO, Folarin OA, Akinboye DO, Yusuf BO, Ebong OO, Sowunmi A, Kyle DE, Milhous W, Wirth DF, Oduola AMJ, 2005. Polymorphisms in Plasmodium falciparum dhfr and dhps genes and age related in vivo sulfadoxine-pyrimethamine resistance in malaria-infected patients from Nigeria. Acta Trop 95 : 183–193. [Google Scholar]
  38. Plowe CV, Djimde A, Bouare M, Doumbo O, Wellems TE, 1995. Pyrimethamine and proguanil resistance conferring mutations in Plasmodium falciparum dihydrofolate-reductase-polymerase chain reaction methods for surveillance in Africa. Am J Trop Med Hyg 52 : 565–568. [Google Scholar]
  39. Djimde AA, Doumbo OK, Traore O, Guindo AB, Kayentao K, Diourte Y, Niare-Doumbo S, Coulibaly D, Kone AK, Cissoko Y, Tekete M, Fofana B, Dicko A, Diallo DA, Wellems TE, Kwiatkowski D, Plowe CV, 2003. Clearance of drug-resistant parasites as a model for protective immunity in Plasmodium falciparum malaria. Am J Trop Med Hyg 69 : 558–563. [Google Scholar]
  40. Olliaro P, Nevill C, Le Bras J, Ringwald P, Musano P, Gerner P, Brasseur P, 1996. Systematic review of amodiaquine treatment in uncomplicated malaria. Lancet 348 : 1196–1201. [Google Scholar]
  41. Sutherland CJ, Alloueche A, McRobert L, Ord R, Leggat J, Snounou G, Pinder M, Target GAT, 2002. Genetic complexity of Plasmodium falciparum gametocytes isolated from peripheral blood of treated Gambian children. Am J Trop Med Hyg 66 : 700–705. [Google Scholar]
  42. Ochong EO, Van Den Broek IVF, Keus K, Nzila A, 2003. Association between chloroquine and amodiaquine resistance and allelic variation in the Plasmodium falciparum multiple drug resistance 1 gene and the chloroquine resistance transporter gene in isolates from the upper Nile in Southern Sudan. Am J Trop Med Hyg 69 : 184–187. [Google Scholar]
  43. Holmgren G, Gil JP, Ferreira PM, Veiga MI, Obonyo CO, Bjorkman A, 2006. Amodiaquine resistant Plasmodium falciparum malaria in vivo is associated with selection pfcrt 76T and pfmdr1 86Y. Infect Genet Evol : 309–314. [Google Scholar]
  44. Sidhu ABR, Pinard DV, Fidock DA, 2002. Chloroquine resistance in Plasmodium falciparum malaria parasites conferred by pfcrt mutations. Science 298 : 210–213. [Google Scholar]
  45. Johnson DJ, Fidock DA, Mungthin M, Lakshamanan V, Sidhu AB, Bray PG, Ward SA, 2004. Evidence for the central role of pfcrt in conferring Plasmodium falciparum resistance to diverse antimalarial agents. Mol Cell 15 : 867–887. [Google Scholar]
  46. Martin RE, Kirk K, 2004. The malaria parasite’s chloroquine resistance transporter is a membrane of the drug metabolic super family. Mol Biol Evol 21 : 1938–1949. [Google Scholar]
  47. Bray PG, Martin RE, Tilley SA, Ward SA, Kirk K, Fidock DA, 2005. Defining the role of Pfcrt in Plasmodium falciparum chloroquine resistance. Mol Microbiol 56 : 323–333. [Google Scholar]
  48. Duraisingh MT, von Seidlein L, Jepson A, Jones P, Sambou I, Pinder M, Warhurst DC, 2000. Linkage disequilibrium between two chromosomally distinct loci associated with increased resistance to chloroquine in Plasmodium falciparum. Parasitology 121 : 1–8. [Google Scholar]
  49. Adagu IS, Warhurst DC, 2001. Plasmodium falciparum: Linkage disequilibrium between loci in chromosomes 7 and 5 and chloroquine selective pressure in Northern Nigeria. Parasitology 123 : 219–224. [Google Scholar]
  50. White NJ, 2002. The assessment of antimalarial drug efficacy. Trends Parasitol 18 : 458–464. [Google Scholar]
  51. Casey GJ, Ginny M, Uranoli M, Mueller I, Reeder JC, Genton B, Cowman AF, 2004. Molecular analysis of Plasmodium falciparum from drug treatment failure patients in Papua New Guinea. Am J Trop Med Hyg 70 : 251–255. [Google Scholar]

Data & Media loading...

  • Received : 04 Jan 2006
  • Accepted : 03 Feb 2006

Most Cited This Month

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error