title: Evidence of dengue virus transmission and factors associated with the presence of anti-dengue virus antibodies in humans in three major towns in Cameroon.
abstract: BACKGROUND
  Dengue is not well documented in Africa. In Cameroon, data are scarce, but dengue infection has been confirmed in humans. We conducted a study to document risk factors associated with anti-dengue virus Immunoglobulin G seropositivity in humans in three major towns in Cameroon.
  
  
  RESULTS
  A cross sectional survey was conducted in Douala, Garoua and Yaounde, using a random cluster sampling design. Participants underwent a standardized interview and were blood sampled. Environmental and housing characteristics were recorded. Randomized houses were prospected to record all water containers, and immature stages of Aedes mosquitoes were collected. Sera were screened for anti-dengue virus IgG and IgM antibodies. Risk factors of seropositivity were tested using logistic regression methods with random effects. Anti-dengue IgG were found from 61.4% of sera in Douala (n = 699), 24.2% in Garoua (n = 728) and 9.8% in Yaounde (n = 603). IgM were found from 0.3% of Douala samples, 0.1% of Garoua samples and 0.0% of Yaounde samples. Seroneutralization on randomly selected IgG positive sera showed that 72% (n = 100) in Douala, 80% (n = 94) in Garoua and 77% (n = 66) in Yaounde had antibodies specific for dengue virus serotype 2 (DENV-2). Age, temporary house walls materials, having water-storage containers, old tires or toilets in the yard, having no TV, having no air conditioning and having travelled at least once outside the city were independently associated with anti-dengue IgG positivity in Douala. Age, having uncovered water containers, having no TV, not being born in Garoua and not breeding pigs were significant risk factors in Garoua. Recent history of malaria, having banana trees and stagnant water in the yard were independent risk factors in Yaounde.
  
  
  CONCLUSIONS
  In this survey, most identified risk factors of dengue were related to housing conditions. Poverty and underdevelopment are central to the dengue epidemiology in Cameroon.
authors.affiliation: Virology Department, Centre Pasteur Cameroon, Member of the International Network of Pasteur Institutes (RIIP), Yaounde, Cameroon.
authors.forename: Maurice
authors.initials: M
authors.lastname: Demanou
authors.affiliation: Epidemiology Department, Centre Pasteur Cameroon, Member of the International Network of Pasteur Institutes (RIIP), Yaounde, Cameroon.
authors.forename: Régis
authors.initials: R
authors.lastname: Pouillot
authors.affiliation: Institut Pasteur du Laos, Laboratoire des Arbovirus et Maladies Virales Émergentes, Vientiane, Lao PDR.
authors.forename: Marc
authors.initials: M
authors.lastname: Grandadam
authors.affiliation: Epidemiology Department, Centre Pasteur Cameroon, Member of the International Network of Pasteur Institutes (RIIP), Yaounde, Cameroon.
authors.forename: Pascal
authors.initials: P
authors.lastname: Boisier
authors.affiliation: Institut Pasteur de Bangui, Bangui, Central African Republic.
authors.forename: Basile
authors.initials: B
authors.lastname: Kamgang
authors.affiliation: IRD, UR 016, Montpellier, France.
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Hervé
authors.affiliation: Institut Pasteur de Madagascar, Antananarivo, Madagascar.
authors.forename: Christophe
authors.initials: C
authors.lastname: Rogier
authors.affiliation: Virology Department, Centre Pasteur Cameroon, Member of the International Network of Pasteur Institutes (RIIP), Yaounde, Cameroon; Institut Pasteur de La Guyane, Laboratoire de Virologie, Cayenne, French Guiana.
authors.forename: Dominique
authors.initials: D
authors.lastname: Rousset
authors.affiliation: UMR MIVEGEC (IRD 224 - CNRS 5290 - UM1 - UM2), Institut de Recherche pour le Développement, Montpellier, France; Equipe Ecologie des Systèmes Vectoriels, Centre International de Recherches Médicales de Franceville, Franceville, Gabon.
authors.forename: Christophe
authors.initials: C
authors.lastname: Paupy
mesh_terms: D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000097:blood; D002163:Cameroon / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003715:Dengue / Q000453:epidemiology / Q000276:immunology / Q000635:transmission* / Q000821:virology; D003716:Dengue Virus / Q000276:immunology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral