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Large differences in prevalence of Pfcrt and Pfmdr1 mutations between Mwanza, Tanzania and Iganga, Uganda-a reflection of differences in policies regarding withdrawal of chloroquine?
- Source :
-
Acta tropica [Acta Trop] 2012 Feb; Vol. 121 (2), pp. 148-51. Date of Electronic Publication: 2011 Nov 16. - Publication Year :
- 2012
-
Abstract
- Background: Malaria is still a major public health problem in the world and sub-Saharan Africa is one of the most affected areas. Efforts to control malaria are highly affected by drug resistance to commonly used antimalarials. The introduction of artemisinin based combination therapy (ACT) as a first line drug seems to be a major step in treatment of uncomplicated malaria, though search for drugs to combine with artemisinins still continues. There have been reports on increased prevalence of the wild type markers Pfcrt 76K and Pfmdr1 86N in some African countries and ideas of using chloroquine (CQ) in intermittent presumptive treatment for adults (IPTa) is coming up. The common combination of artemether and lumefantrine even selects for parasites that are wild type at these positions. This study is comparing prevalence of mutation at these two positions in two East African countries with ACT as their first line drug but following somewhat different drug policies regarding CQ. In Tanzania CQ was stopped in 2001 but in Uganda CQ was retained in combination with sulfadoxine-pyrimethamine (SP) and used in home based management of fever for some time. SP is still used in IPT for pregnant women.<br />Methods: Blood smears and dried blood spots on Whatman filter papers were collected from 100 patients with uncomplicated malaria in Mwanza, Tanzania and 100 patients from Iganga, Uganda. DNA was extracted from all samples using Tris EDTA method. PCR and RFLP were performed and sequencing done on Pfcrt amplification products.<br />Results: The prevalence of K76T mutations at Pfcrt in samples from Mwanza, Tanzania was 40.5% (34/84) and 100% (100/100) in samples from Iganga, Uganda. Prevalence of N86Y mutations in Pfmdr1 was 16.9% (13/77) and 77.7% (63/81) in samples from Mwanza and Iganga, respectively. The re-emergence of CQ sensitive isolates in Mwanza, Tanzania showed the haplotype CVMNK typical for wild type isolates.<br />Conclusions: The prevalence of CQ resistant parasites in Mwanza, Tanzania is low compared to the existing high level of resistant parasites in Iganga, Uganda. This could be an indication that CQ may become useful in the future in Tanzania. This study shows clearly that there is a difference in mutations at these positions in these two countries implementing similar but somewhat different drug policies. In Uganda the drug resistance has reached fixation while in Tanzania the prevalence is going down.<br /> (Copyright © 2011 Elsevier B.V. All rights reserved.)
- Subjects :
- Adult
Animals
Child
Child, Preschool
DNA, Protozoan genetics
DNA, Protozoan isolation & purification
Female
Gene Frequency
Genotype
Health Policy
Humans
Infant
Malaria, Falciparum drug therapy
Male
Polymerase Chain Reaction
Polymorphism, Restriction Fragment Length
Pregnancy
Sequence Analysis, DNA
Tanzania
Uganda
Antimalarials administration & dosage
Chloroquine administration & dosage
Drug Resistance
Malaria, Falciparum parasitology
Membrane Transport Proteins genetics
Multidrug Resistance-Associated Proteins genetics
Mutation, Missense
Protozoan Proteins genetics
Subjects
Details
- Language :
- English
- ISSN :
- 1873-6254
- Volume :
- 121
- Issue :
- 2
- Database :
- MEDLINE
- Journal :
- Acta tropica
- Publication Type :
- Academic Journal
- Accession number :
- 22118982
- Full Text :
- https://doi.org/10.1016/j.actatropica.2011.11.004