Volume 100, Issue 5
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



Prevalence of and risk factors associated with polymerase chain reaction (PCR)-determined positivity were assessed on day 3 after initiation of treatment, pre-implementation and up to 8 years post-deployment of artemether–lumefantrine as first-line treatment for uncomplicated malaria in Bagamoyo district, Tanzania. Samples originated from previously reported trials conducted between 2006 and 2014. Cytochrome b-nested PCR was used to detect malaria parasites from blood samples collected on a filter paper on day 3. Chi-square and McNemar chi-squared tests, logistic regression models, and analysis of variance were used as appropriate. Primary outcome was based on the proportion of patients with day 3 PCR-determined positivity. Overall, 256/584 (43.8%) of screened patients had day 3 PCR-determined positivity, whereas only 2/584 (0.3%) had microscopy-determined asexual parasitemia. Day 3 PCR-determined positivity increased from 28.0% (14/50) in 2006 to 74.2% (132/178) in 2007–2008 and declined, thereafter, to 36.0% (50/139) in 2012–2013 and 27.6% (60/217) in 2014. When data were pooled, pretreatment microscopy-determined asexual parasitemia ≥ 100,000/µL, hemoglobin < 10 g/dL, age < 5 years, temperature ≥ 37.5°C, and year of study 2007–2008 and 2012–2013 were significantly associated with PCR-determined positivity on day 3. Significant increases in multidrug resistance gene 1 N86 and chloroquine resistant transporter K76 across years were not associated with PCR-determined positivity on day 3. No statistically significant association was observed between day 3 PCR-determined positivity and PCR-adjusted recrudescence. Day 3 PCR-determined positivity remained common in patients treated before and after implementation of artemether–lumefantrine in Bagamoyo district, Tanzania. However, its presence was associated with pretreatment characteristics. Trials registration numbers: NCT00336375, ISRCTN69189899, NCT01998295, and NCT02090036.

[open-access] This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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  1. World Health Organization, 2014. World Malaria Report 2014. Geneva, Switzerland: WHO. [Google Scholar]
  2. World Health Organization, 2015. World Malaria Report 2015. Geneva, Switzerland: WHO. [Google Scholar]
  3. White NJ, , 2008. Qinghaosu (artemisinin): the price of success. Science 320: 330334. [Google Scholar]
  4. Dondorp AM, 2009. Artemisinin resistance in Plasmodium falciparum malaria. N Engl J Med 361: 455467. [Google Scholar]
  5. World Health Organization, 2016. Artemisinin and Artemisinin-Based Combination Therapy Resistance. Geneva, Switzerland: WHO. [Google Scholar]
  6. Ariey F, 2014. A molecular marker of artemisinin-resistant Plasmodium falciparum malaria. Nature 505: 5055. [Google Scholar]
  7. Noedl H, 2010. Artemisinin resistance in Cambodia: a clinical trial designed to address an emerging problem in southeast Asia. Clin Infect Dis 51: e82e89. [Google Scholar]
  8. Saunders DL, Vanachayangkul P, Lon C, , 2014. Dihydroartemisinin-piperaquine failure in Cambodia. N Engl J Med 371: 484485. [Google Scholar]
  9. Lu F, 2017. Emergence of indigenous artemisinin-resistant Plasmodium falciparum in Africa. N Engl J Med 376: 991993. [Google Scholar]
  10. Ajayi NA, Ukwaja KN, , 2013. Possible artemisinin-based combination therapy-resistant malaria in Nigeria: a report of three cases. Rev da Soc Bras Med Trop 46: 525527. [Google Scholar]
  11. Taylor SM, 2014. Absence of putative artemisinin resistance mutations among Plasmodium falciparum in sub-Saharan Africa: a molecular epidemiologic study. J Infect Dis 211: 680688. [Google Scholar]
  12. Kamau E, 2015. K13-propeller polymorphisms in Plasmodium falciparum parasites from sub-Saharan Africa. J Infect Dis 211: 13521355. [Google Scholar]
  13. Ashley E, 2014. Spread of artemisinin resistance in Plasmodium falciparum malaria. N Engl J Med 371: 411423. [Google Scholar]
  14. Maiga AW, 2012. No evidence of delayed parasite clearance after oral artesunate treatment of uncomplicated falciparum malaria in Mali. Am J Trop Med Hyg 87: 2328. [Google Scholar]
  15. Mwaiswelo R, Ngasala B, Gil JP, Malmberg M, Jovel I, Xu W, Premji Z, Mmbando BP, Bjorkman A, Mårtensson A, , 2017. Sustained high cure rate of artemether–lumefantrine against uncomplicated Plasmodium falciparum malaria after 8 years of its wide-scale use in Bagamoyo district, Tanzania. Am J Trop Med Hyg 97: 526532. [Google Scholar]
  16. Beshir KB, 2013. Residual Plasmodium falciparum parasitemia in Kenyan children after artemisinin-combination therapy is associated with increased transmission to mosquitoes and parasite recurrence. J Infect Dis 208: 20172024. [Google Scholar]
  17. Kiaco K, Teixeira J, Machado M, do Rosário V, Lopes D, , 2015. Evaluation of artemether-lumefantrine efficacy in the treatment of uncomplicated malaria and its association with pfmdr1, pfatpase6 and K13-propeller polymorphisms in Luanda, Angola. Malar J 14: 504. [Google Scholar]
  18. Djimdé A, 2003. Clearance of drug-resistant parasites as a model for protective immunity in Plasmodium falciparum malaria. Am J Trop Med Hyg 69: 558563. [Google Scholar]
  19. Zwang J, Dorsey G, Mårtensson A, d’Alessandro U, Ndiaye JL, Karema C, Djimde A, Brasseur P, Olliaro P, , 2014. Plasmodium falciparum clearance in clinical studies of artesunate-amodiaquine and comparator treatments in sub-Saharan Africa, 1999–2009. Malar J 13: 114. [Google Scholar]
  20. WWARN Artemisinin based Combination Therapy (ACT) Africa Baseline Study Group Dahal P, d’Alessandro U, Dorsey G, Guerin PJ, Nsanzabana C, Price RN, Sibley CH, Stepniewska K, Talisuna AO, , 2015. Clinical determinants of early parasitological response to ACTs in African patients with uncomplicated falciparum malaria: a literature review and meta-analysis of individual patient data. BMC Med 13: 212. [Google Scholar]
  21. White NJ, , 2011. The parasite clearance curve. Malar J 10: 278. [Google Scholar]
  22. Carlsson AM, 2011. Plasmodium falciparum population dynamics during the early phase of anti-malarial drug treatment in Tanzanian children with acute uncomplicated malaria. Malar J 10: 380. [Google Scholar]
  23. Ngasala BE, 2011. Efficacy and effectiveness of artemether-lumefantrine after initial and repeated treatment in children < 5 years of age with acute uncomplicated Plasmodium falciparum malaria in rural Tanzania: a randomized trial. Clin Infect Dis 52: 873882. [Google Scholar]
  24. Mwaiswelo R, Ngasala BE, Jovel I, Gosling R, Premji Z, Poirot E, Mmbando BP, Björkman A, Mårtensson A, , 2016. Safety of a single low-dose of primaquine in addition to standard artemether-lumefantrine regimen for treatment of acute uncomplicated Plasmodium falciparum malaria in Tanzania. Malar J 15: 316. [Google Scholar]
  25. Gething PW, Patil AP, Smith DL, Guerra C, Elyazar IRF, Johnston GL, Tatem AJ, Hay SI, , 2011. A new world malaria map: Plasmodium falciparum endemicity in 2010. Malar J 10: 378. [Google Scholar]
  26. National Malaria Control Programme, 2006. National Guidelines for Diagnosis and Treatment of Malaria. Dar es Salaam, United Republic of Tanzania NMCP. [Google Scholar]
  27. National Malaria Control Programme, 2010. Tanzania Malaria Programme Review 2010. Programme Review Proposal. Dar es Salaam, United Republic of Tanzania NMCP. [Google Scholar]
  28. Mwaiswelo R, Ngasala BE, Jovel IT, Aydin-schmidt B, Gosling R, Premji Z, Mmbando B, Björkman A, Mårtensson A, , 2016. Adding a single low-dose of primaquine (0.25 mg/kg) to artemether-lumefantrine did not compromise treatment outcome of uncomplicated Plasmodium falciparum malaria in Tanzania: a randomized, single-blinded clinical trial. Malar J 15: 435. [Google Scholar]
  29. World Health Organization, 2009. Methods for Surveillance of Antimalarial Drug Efficacy. Geneva, Switzerland: WHO. [Google Scholar]
  30. Hsiang MS, Lin MS, Dokomajilar M, Kemere J, Pilcher CD, Greenhouse B, , 2010. PCR-based pooling of dried blood spots for detection of malaria parasites: optimization and application to a cohort. J Clin Microbiol 48: 35393543. [Google Scholar]
  31. Morris U, 2013. Rapid diagnostic tests for molecular surveillance of Plasmodium falciparum malaria -assessment of DNA extraction methods and field applicability. Malar J 12: 106. [Google Scholar]
  32. Steenkeste N, Incardona S, Chy S, Duval L, Ekala M-T, Lim P, Hewitt S, Sochantha T, Socheat D, Rogier C, , 2009. Towards high-throughput molecular detection of Plasmodium: new approaches and molecular markers. Malar J 8: 86. [Google Scholar]
  33. Djimdé A, 2001. A molecular marker for chloroquine-resistant falciparum malaria. N Engl J Med 344: 257263. [Google Scholar]
  34. Snounou G, Zhu X, Siripoon N, Jarra W, Thaithong S, Brown K, Viriyakosol S, , 1999. Biased distribution of mspl populations in Thailand and msp2 allelic variants in Plasmodium falciparum. Trans R Soc Trop Med Hyg 2: 369374. [Google Scholar]
  35. White NJ, , 2017. Malaria parasite clearance. Malar J 16: 88. [Google Scholar]
  36. Le Manach C, 2013. Fast in vitro methods to determine the speed of action and the stage-specificity of anti-malarials in Plasmodium falciparum. Malar J 12: 424. [Google Scholar]
  37. White NJ, Van Vugt M, Ezzet F, , 1999. Clinical pharmacokinetics and pharmacodynamics of artemether-lumefantrine. Clin Pharmacokinet 37: 105125. [Google Scholar]
  38. Lopera-Mesa TM, 2013. Plasmodium falciparum clearance rates in response to artesunate in Malian children with malaria: effect of acquired immunity. J Infect Dis 207: 16551663. [Google Scholar]
  39. Muhindo MK, 2014. Early parasite clearance following artemisinin- based combination therapy among Ugandan children with uncomplicated Plasmodium falciparum malaria. Malar J 13: 32. [Google Scholar]
  40. Malmberg M, 2013. Temporal trends of molecular markers associated with artemether-lumefantrine tolerance/resistance in Bagamoyo district, Tanzania. Malar J 12: 103. [Google Scholar]
  41. Okombo J, Kamau AW, Marsh K, Sutherland CJ, Ochola-oyier LI, , 2014. Temporal trends in prevalence of Plasmodium falciparum drug resistance alleles over two decades of changing antimalarial policy in coastal Kenya. Int J Parasitol Drug Resist 4: 152163. [Google Scholar]
  42. Sutherland CJ, Alloueche A, Curtis J, Drakeley CJ, Ord R, Duraisingh M, Greenwood BM, Pinder M, Warhurst D, Targett GA, , 2002. Gambian children successfully treated with chloroquine can harbor and transmit Plasmodium falciparum gametocytes carrying resistance genes. Am J Trop Med Hyg 67: 578585. [Google Scholar]
  43. Ochong EO, van den Broek IV, Keus K, Nzila A, , 2003. Short report: 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: 184187. [Google Scholar]
  44. Humphreys GS, Merinopoulos I, Ahmed J, Whitty CJM, Mutabingwa TK, Sutherland CJ, Hallett RL, , 2007. Amodiaquine and artemether-lumefantrine select distinct alleles of the Plasmodium falciparum mdr1 gene in Tanzanian children treated for uncomplicated malaria. Antimicrob Agents Chemother 51: 991997. [Google Scholar]
  45. Chang H, 2016. Persistence of Plasmodium falciparum parasitemia after artemisinin combination therapy: evidence from a randomized trial in Uganda. Sci Rep 6: 26330. [Google Scholar]

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  • Received : 06 Sep 2018
  • Accepted : 16 Dec 2018
  • Published online : 11 Mar 2019

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