Plasmodium vivax multidrug resistance-1 gene polymorphism in French Guiana

Emilie Faway (1, 2) , Lise Musset (3) , Stéphane Pelleau (3) , Béatrice Volney (3) , Jessica Casteras (3) , Valérie Caro (4) , Didier Menard (5) , Sébastien Briolant (6, 7, 2) , Eric Legrand (3, 8)

1 UNamur - Université de Namur [Namur]
2 Institut Pasteur de la Guyane
3 CNR - laboratoire associé - Centre National de Référence du Paludisme [Cayenne, Guyane française]
4 ERI - Environnement et Risques infectieux - Environment and Infectious Risks
5 Institut Pasteur du Cambodge
6 IRBA - Institut de Recherche Biomédicale des Armées [Brétigny-sur-Orge]
7 Direction Interarmées du Service de Santé en Guyane
8 Génétique et Génomique des Insectes vecteurs

BACKGROUND: Plasmodium vivax malaria is a major public health problem in French Guiana. Some cases of resistance to chloroquine, the first-line treatment used against P. vivax malaria, have been described in the Brazilian Amazon region. The aim of this study is to investigate a possible dispersion of chloroquine-resistant P. vivax isolates in French Guiana. The genotype, polymorphism and copy number variation, of the P. vivax multidrug resistance gene-1 (pvmdr1) have been previously associated with modification of the susceptibility to chloroquine. METHODS: The pvmdr1 gene polymorphism was evaluated by sequencing and copy number variation was assessed by real-time PCR, in P. vivax isolates obtained from 591 symptomatic patients from 1997 to 2013. RESULTS: The results reveal that 1.0% [95% CI 0.4-2.2] of French Guiana isolates carry the mutations Y976F and F1076L, and that the proportion of isolates with multiple copies of pvmdr1 has significantly decreased over time, from 71.3% (OR = 6.2 [95% CI 62.9-78.7], p < 0.0001) in 1997-2004 to 12.8% (OR = 0.03 [95% CI 9.4-16.9], p < 0.0001) in 2009-2013. A statistically significant relationship was found between Guf-A (harboring the single mutation T958M) and Sal-1 (wild type) alleles and pvmdr1 copy number. CONCLUSIONS: Few P. vivax isolates harboring chloroquine-resistant mutations in the pvmdr1 gene are circulating in French Guiana. However, the decrease in the prevalence of isolates carrying multiple copies of pvmdr1 might indicate that the P. vivax population in French Guiana is evolving towards a decreased susceptibility to chloroquine.

Domaines: Parasitologie

Emilie Faway, Lise Musset, Stéphane Pelleau, Béatrice Volney, Jessica Casteras, et al.. Plasmodium vivax multidrug resistance-1 gene polymorphism in French Guiana. Malaria Journal, 2016, 15 (1), pp.540. ⟨10.1186/s12936-016-1595-9⟩. ⟨pasteur-01400964⟩