title: Seroprevalence of dengue virus antibodies in asymptomatic Costa Rican children, 2002-2003: a pilot study.
abstract: OBJECTIVE
  Since 1993 dengue has become more frequent in Costa Rica. Adults have been the most affected population, while children have remained virtually unharmed. So far no studies have investigated how many asymptomatic children have been affected by this virus. This pilot study documents the seroprevalence, measured as the presence of IgG antibodies, of dengue virus in asymptomatic children from two different geographical areas.
  
  
  METHODS
  This descriptive, prospective epidemiologic study compared the presence of antibodies in children who live in a coastal region of a tropical country where dengue is endemic, and an inland area where dengue is not endemic. An enzyme-linked immunosorbent assay was used to test the serum for dengue virus IgG antibodies. None of the children had a prior history of dengue, fever, immunosuppressive therapy or underlying disease.
  
  
  RESULTS
  During the period from July 2002 to July 2003, 103 children were recruited from each area. In the costal region we found a seroprevalence of 36.9%. In the inland area seroprevalence was 2.9%.
  
  
  CONCLUSIONS
  We found a substantial number of asymptomatic infections in Costa Rican children. This greatly increases the risk of dengue hemorrhagic fever or dengue shock syndrome in these children, in whom previous dengue infection had gone undetected. Preventive efforts should be targeted at the costal region due to the higher prevalence in this area.
authors.affiliation: Pediatric Infectious Diseases Division, Hospital Nacional de Niños, San Jose, Costa Rica.
authors.forename: Roberto
authors.initials: R
authors.lastname: Iturrino-Monge
authors.forename: Maria L
authors.initials: ML
authors.lastname: Avila-Agüero
authors.forename: Claudio R
authors.initials: CR
authors.lastname: Avila-Agüero
authors.forename: Tatiana
authors.initials: T
authors.lastname: Moya-Moya
authors.forename: Alejandro
authors.initials: A
authors.lastname: Cañas-Coto
authors.forename: Kattia
authors.initials: K
authors.lastname: Camacho-Badilla
authors.forename: Betzana
authors.initials: B
authors.lastname: Zambrano-Mora
mesh_terms: D000914:Antibodies, Viral / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D003364:Costa Rica / Q000453:epidemiology; D003716:Dengue Virus / Q000276:immunology*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007223:Infant; D008297:Male; D010865:Pilot Projects; D011446:Prospective Studies; D016036:Seroepidemiologic Studies; D019595:Severe Dengue / Q000097:blood* / Q000453:epidemiology*
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G