title: Epidemiology of Chikungunya Virus Outbreaks in Guadeloupe and Martinique, 2014: An Observational Study in Volunteer Blood Donors.
abstract: During Dec-2013, a chikungunya virus (CHIKV) outbreak was first detected in the French-West Indies. Subsequently, the virus dispersed to other Caribbean islands, continental America and many islands in the Pacific Ocean. Previous estimates of the attack rate were based on declaration of clinically suspected cases.
  
  
  
  Individual testing for CHIKV RNA of all (n = 16,386) blood donations between Feb-24th 2014 and Jan-31st 2015 identified 0·36% and 0·42% of positives in Guadeloupe and Martinique, respectively. The incidence curves faithfully correlated with those of suspected clinical cases in the general population of Guadeloupe (abrupt epidemic peak), but not in Martinique (flatter epidemic growth). No significant relationship was identified between CHIKV RNA detection and age-classes or blood groups. Prospective (Feb-2014 to Jan-2015; n = 9,506) and retrospective (Aug-2013 to Feb-2014; n = 6,559) seroepidemiological surveys in blood donors identified a final seroprevalence of 48·1% in Guadeloupe and 41·9% in Martinique. Retrospective survey also suggested the absence or limited "silent" CHIKV circulation before the outbreak. Parameters associated with increased seroprevalence were: Gender (M>F), KEL-1, [RH+1/KEL-1], [A/RH+1] and [A/RH+1/KEL-1] blood groups in Martiniquan donors. A simulation model based on observed incidence and actual seroprevalence values predicted 2·5 and 2·3 days of asymptomatic viraemia in Martiniquan and Guadeloupian blood donors respectively.
  
  
  
  This study, implemented promptly with relatively limited logistical requirements during CHIKV emergence in the Caribbean, provided unique information regarding retrospective and prospective epidemiology, infection risk factors and natural history of the disease. In the stressful context of emerging infectious disease outbreaks, blood donor-based studies can serve as robust and cost-effective first-line tools for public health surveys.
authors.affiliation: Etablissement Français du Sang (EFS) Alpes Méditerranée, Marseille, France.|Aix Marseille Université, IRD U190, INSERM U1207, EHESP: "Emergence des Pathologies Virales", Marseille, France.|Institut Hospitalo Universitaire (IHU) Méditerranée Infection, Marseille, France.|Etablissement Français du Sang (EFS) La Plaine-Saint-Denis, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Gallian
authors.affiliation: Aix Marseille Université, IRD U190, INSERM U1207, EHESP: "Emergence des Pathologies Virales", Marseille, France.|Institut Hospitalo Universitaire (IHU) Méditerranée Infection, Marseille, France.|Centre National de Référence (CNR) des Arbovirus, Institut de Recherche Biomédicale des Armée, Hôpital d'Instruction des Armées Laveran, Marseille, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Leparc-Goffart
authors.affiliation: Etablissement Français du Sang (EFS) Martinique, Fort de France, France.
authors.forename: Pascale
authors.initials: P
authors.lastname: Richard
authors.affiliation: Etablissement Français du Sang (EFS) Guadeloupe-Guyane, Point a Pitre, France.
authors.forename: Françoise
authors.initials: F
authors.lastname: Maire
authors.affiliation: Aix Marseille Université, IRD U190, INSERM U1207, EHESP: "Emergence des Pathologies Virales", Marseille, France.|Institut Hospitalo Universitaire (IHU) Méditerranée Infection, Marseille, France.|Centre National de Référence (CNR) des Arbovirus, Institut de Recherche Biomédicale des Armée, Hôpital d'Instruction des Armées Laveran, Marseille, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Flusin
authors.affiliation: Etablissement Français du Sang (EFS) La Plaine-Saint-Denis, France.
authors.forename: Rachid
authors.initials: R
authors.lastname: Djoudi
authors.affiliation: Etablissement Français du Sang (EFS) Alpes Méditerranée, Marseille, France.|Institut Hospitalo Universitaire (IHU) Méditerranée Infection, Marseille, France.
authors.forename: Jacques
authors.initials: J
authors.lastname: Chiaroni
authors.affiliation: Aix Marseille Université, IRD U190, INSERM U1207, EHESP: "Emergence des Pathologies Virales", Marseille, France.|Institut Hospitalo Universitaire (IHU) Méditerranée Infection, Marseille, France.
authors.forename: Remi
authors.initials: R
authors.lastname: Charrel
authors.affiliation: Etablissement Français du Sang (EFS) La Plaine-Saint-Denis, France.|Université de Franche- Comté, Besançon, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Tiberghien
authors.affiliation: Aix Marseille Université, IRD U190, INSERM U1207, EHESP: "Emergence des Pathologies Virales", Marseille, France.|Institut Hospitalo Universitaire (IHU) Méditerranée Infection, Marseille, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: de Lamballerie
mesh_terms: D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood; D001769:Blood / Q000821:virology*; D001782:Blood Donors / Q000706:statistics & numerical data; D065632:Chikungunya Fever / Q000097:blood* / Q000453:epidemiology / Q000821:virology; D002646:Chikungunya virus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D005260:Female; D019430:Guadeloupe / Q000453:epidemiology; D006801:Humans; D008297:Male; D008395:Martinique / Q000453:epidemiology; D008875:Middle Aged; D011446:Prospective Studies; D012189:Retrospective Studies; D016036:Seroepidemiologic Studies; D014838:Volunteers; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral