Volume 11 Supplement 1

Challenges in malaria research

Open Access

Microsatellite characterization of Plasmodium vivax in pregnant women on the Thai–Myanmar border

  • Supinya Thanapongpichat1,
  • Mallika Imwong2,
  • Rose McGready3,
  • Nicholas PJ Day4, 5,
  • Francois Nosten3,
  • Georges Snounou6, 7 and
  • Nicholas J White4, 5
Malaria Journal201211(Suppl 1):P137

DOI: 10.1186/1475-2875-11-S1-P137

Published: 9 November 2012


Plasmodium vivax infections in pregnant women are associated with low birth weight and anemia. Genotyping of P.vivax is useful to study P. vivax in pregnancy, though it is still remains challenging to distinguish between relapse from hypnozoite stage and recrudescence from blood stage following treatment. A genetic investigation of P.vivax in pregnancy on the Thai-Burmese border, comparing the genotype between at follow up with the day of admission for pregnant patients and non pregnant patients was undertaken in this study.

Materials and methods

One hundred and sixteen blood samples infected with P.vivax were isolated from 18 pregnant women with ≥2 episodes obtained from whole blood (12 women had 2 reappearances, 4 and 2 women had 3 and 4 reappearances, respectively) and 18 non-pregnant women with 2 consecutive episodes collected on dried blood spot. All samples were genotyped with eight microsatellite markers. Analyses were performed for genetic diversity, multiplicity of infection (MOI), and comparison of genotypes for individual episodes detected in samples.


Eight microsatellite loci, 6 to 15 alleles were found at each locus. The mean number of alleles per locus was 1.40 and 1.17 (p<0.001) for pregnant and non-pregnant patients, respectively. The overall mean expected heterogygosity (He) was 0.845 in both groups. In pregnant patients, the multiplicity of infection (MOI) was 1.85 while it was 1.44 (p=0.028) in non-pregnant patients.

The greater number of minor alleles in pregnant patients may either the nature of the sample.

Combined genetic data from days of follow and day of admission showed that genotypes were different 57 % (25/44) of those pregnant patients and 58 % (21/36) of non-pregnant patients (p=0.891).


This study confirmed that different P.vivax genotypes were found during follow up when compared to day of admission in both groups.



Supported by grant from under the program "Strategic Scholarships for Frontier Research Network for the Ph.D." Program Thai Doctoral degree from the Office of the Higher Education Commission, Thailand and the Wellcome Trust of Great Britain.

Authors’ Affiliations

Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University
Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University
Shoklo Malaria Research Unit
Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University
Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital University of Oxford
Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Recherche
Faculté de Médecine Pitié-Salpêtrière, Université Pierre & Marie Curie


© Thanapongpichat et al; licensee BioMed Central Ltd. 2012

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


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