title: The hide and seek of Plasmodium vivax in West Africa: report from a large-scale study in Beninese asymptomatic subjects.
abstract: Plasmodium vivax is considered to be absent from western Africa, where the prevalence of Duffy-negative red blood cell phenotype proves to be high. Several studies have, however, detected P. vivax infection cases in this part of Africa, raising the question of what is the actual prevalence of P. vivax in local populations.
  
  
  
  The presence of P. vivax was investigated in a large population of healthy blood donors in Benin using microscopy, serology and molecular detection. The seroprevalence was measured with species-specific ELISA using two recombinant P. vivax proteins, namely rPvMSP1 and rPvCSP1. Specific molecular diagnosis of P. vivax infection was carried out using nested-PCR. The performances and cut-off values of both rPvCSP1 and rPvMSP1 ELISA were first assessed using sera from P. vivax-infected patients and from non-exposed subjects.
  
  
  
  Among 1234 Beninese blood donors, no parasites were detected when using microscopy, whereas 28.7% (354/1234) of patients exhibited had antibodies against rPvMSP1, 21.6% (266/1234) against rPvCSP1, and 15.2% (187/1234) against both. Eighty-four samples were selected for nested-PCR analyses, of which 13 were positive for P. vivax nested-PCR and all Duffy negative.
  
  
  
  The results of the present study highlight an unexpectedly high exposure of Beninese subjects to P. vivax, resulting in sub-microscopic infections. This suggests a probably underestimated and insidious parasite presence in western Africa. While the vaccination campaigns and therapeutic efforts are all focused on Plasmodium falciparum, it is also essential to consider the epidemiological impact of P. vivax.
authors.affiliation: Laboratoire de Parasitologie Mycologie, CHU Gabriel Montpied, Clermont-Ferrand, France. ppoirier@chu-clermontferrand.fr.|Laboratoire Microorganismes: Génome et Environnement, UMR CNRS 6023, Aubière, France. ppoirier@chu-clermontferrand.fr.
authors.forename: Philippe
authors.identifier: 0000-0001-8849-5922
authors.initials: P
authors.lastname: Poirier
authors.affiliation: Institut de Parasitologie et de Pathologie Tropicale, EA 7292, Fédération de Médecine Translationnelle, Université de Strasbourg, Strasbourg, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Doderer-Lang
authors.affiliation: Laboratoire de Biochimie et de Biologie Moléculaire, Université d'Abomey Calavi, Cotonou, Benin.
authors.forename: Pascal S
authors.initials: PS
authors.lastname: Atchade
authors.affiliation: Institut de Parasitologie et de Pathologie Tropicale, EA 7292, Fédération de Médecine Translationnelle, Université de Strasbourg, Strasbourg, France.|Laboratoire de Parasitologie et de Mycologie Médicale, Plateau Technique de Microbiologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Lemoine
authors.affiliation: Institut de Parasitologie et de Pathologie Tropicale, EA 7292, Fédération de Médecine Translationnelle, Université de Strasbourg, Strasbourg, France.
authors.forename: Marie-Louise Coquelin
authors.initials: MC
authors.lastname: de l'Isle
authors.affiliation: Institut de Parasitologie et de Pathologie Tropicale, EA 7292, Fédération de Médecine Translationnelle, Université de Strasbourg, Strasbourg, France.|Laboratoire de Parasitologie et de Mycologie Médicale, Plateau Technique de Microbiologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Abou-Bacar
authors.affiliation: Institut de Parasitologie et de Pathologie Tropicale, EA 7292, Fédération de Médecine Translationnelle, Université de Strasbourg, Strasbourg, France.|Laboratoire de Parasitologie et de Mycologie Médicale, Plateau Technique de Microbiologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.
authors.forename: Alexander W
authors.initials: AW
authors.lastname: Pfaff
authors.affiliation: Institut de Parasitologie et de Pathologie Tropicale, EA 7292, Fédération de Médecine Translationnelle, Université de Strasbourg, Strasbourg, France.|Laboratoire de Parasitologie et de Mycologie Médicale, Plateau Technique de Microbiologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.
authors.forename: Julie
authors.initials: J
authors.lastname: Brunet
authors.affiliation: Institut de Parasitologie et de Pathologie Tropicale, EA 7292, Fédération de Médecine Translationnelle, Université de Strasbourg, Strasbourg, France.
authors.forename: Lydia
authors.initials: L
authors.lastname: Arnoux
authors.affiliation: Laboratoire de Parasitologie et de Mycologie Médicale, Plateau Technique de Microbiologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.
authors.forename: Elodie
authors.initials: E
authors.lastname: Haar
authors.affiliation: Institut de Parasitologie et de Pathologie Tropicale, EA 7292, Fédération de Médecine Translationnelle, Université de Strasbourg, Strasbourg, France.|Laboratoire de Parasitologie et de Mycologie Médicale, Plateau Technique de Microbiologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Filisetti
authors.affiliation: Institut de Parasitologie et de Pathologie Tropicale, EA 7292, Fédération de Médecine Translationnelle, Université de Strasbourg, Strasbourg, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Perrotey
authors.affiliation: Laboratoire de Biochimie et de Biologie Moléculaire, Université d'Abomey Calavi, Cotonou, Benin.
authors.forename: Nicodeme W
authors.initials: NW
authors.lastname: Chabi
authors.affiliation: Laboratoire de Biochimie et de Biologie Moléculaire, Université d'Abomey Calavi, Cotonou, Benin.
authors.forename: Casimir D
authors.initials: CD
authors.lastname: Akpovi
authors.affiliation: Agence Nationale pour la Transfusion Sanguine (Ministère de la Santé), Cotonou, Benin.
authors.forename: Ludovic
authors.initials: L
authors.lastname: Anani
authors.affiliation: Agence Nationale pour la Transfusion Sanguine (Ministère de la Santé), Cotonou, Benin.
authors.forename: André
authors.initials: A
authors.lastname: Bigot
authors.affiliation: Laboratoire de Biochimie et de Biologie Moléculaire, Université d'Abomey Calavi, Cotonou, Benin.
authors.forename: Ambaliou
authors.initials: A
authors.lastname: Sanni
authors.affiliation: Institut de Parasitologie et de Pathologie Tropicale, EA 7292, Fédération de Médecine Translationnelle, Université de Strasbourg, Strasbourg, France. candolfi@unistra.fr.|Laboratoire de Parasitologie et de Mycologie Médicale, Plateau Technique de Microbiologie, Hôpitaux Universitaires de Strasbourg, Strasbourg, France. candolfi@unistra.fr.
authors.forename: Ermanno
authors.initials: E
authors.lastname: Candolfi
mesh_terms: D000913:Antibodies, Protozoan / Q000097:blood*; D058345:Asymptomatic Infections / Q000453:epidemiology*; D001541:Benin / Q000453:epidemiology; D001782:Blood Donors; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D016780:Malaria, Vivax / Q000453:epidemiology* / Q000473:pathology*; D008297:Male; D016133:Polymerase Chain Reaction; D016036:Seroepidemiologic Studies
chemical_list: D000913:Antibodies, Protozoan
keywords: Benin; Blood donors; CSP1; ELISA; MSP1; Malaria; Plasmodium vivax; Western Africa