title: A comparative study on active and passive epidemiological surveillance for dengue in five countries of Latin America.
abstract: BACKGROUND
  Dengue is a notifiable infectious disease in many countries, but under-reporting of cases to National Epidemiological Surveillance Systems (NESSs) conceals the true extent of the disease burden. The incidence of dengue identified in a cohort study was compared with those reported to NESSs.
  
  
  METHODS
  A randomized, placebo-controlled study was undertaken in Brazil, Colombia, Honduras, Mexico, and Puerto Rico to assess the efficacy of a tetravalent dengue vaccine (CYD-TDV) in children aged 9-16 years. The incidence of dengue in the placebo group was compared with that reported to NESSs in a similar age group (10-19 years) from June 2011 to April 2014.
  
  
  RESULTS
  Three thousand six hundred and fifteen suspected dengue cases were identified in the study over 13527 person-years of observation. The overall incidence of confirmed dengue was 2.9 per 100 person-years (range 1.5 to 4.1 per 100 person-years). In the NESSs combined, over 3.2 million suspected dengue cases were reported during the same period, corresponding to over 1 billion person-years of observation. The incidence of confirmed dengue reported by the NESSs in the same locality where the study took place was 0.286 per 100 person-years across Brazil, Colombia, and Mexico (range 0.180 to 0.734 per 100 person-years). The incidence of confirmed dengue was 10.0-fold higher in the study than that reported to NESSs in the same localities (range 3.5- to 19.4-fold higher).
  
  
  CONCLUSIONS
  There is a substantial under-reporting of dengue in the NESSs. Understanding the level of under-reporting would allow more accurate estimates of the dengue burden in Latin America.
authors.affiliation: Sanofi Pasteur LATAM, Av. Universidad 1738, Col. Coyoacán, Mexico D.F. C.P. 04000. Electronic address: elsa.sarti@sanofipasteur.com.
authors.forename: Elsa
authors.initials: E
authors.lastname: Sarti
authors.affiliation: Global Epidemiology, Sanofi Pasteur, Lyon, France.
authors.forename: Maïna
authors.initials: M
authors.lastname: L'Azou
authors.affiliation: Instituto Nacional de Salud, Bogotá DC, Colombia.
authors.forename: Marcela
authors.initials: M
authors.lastname: Mercado
authors.affiliation: Universidad Nacional Autónoma de México Ciudad Universitaria, Distrito Federal, Mexico.
authors.forename: Pablo
authors.initials: P
authors.lastname: Kuri
authors.affiliation: Universidade Federal de Goias, Goiania, Brazil.
authors.forename: Joao Bosco
authors.initials: JB
authors.lastname: Siqueira
authors.affiliation: Sanofi Pasteur LATAM, Av. Universidad 1738, Col. Coyoacán, Mexico D.F. C.P. 04000.
authors.forename: Erick
authors.initials: E
authors.lastname: Solis
authors.affiliation: Sanofi Pasteur, Pennsylvania, USA.
authors.forename: Fernando
authors.initials: F
authors.lastname: Noriega
authors.affiliation: Global Epidemiology, Sanofi Pasteur, Lyon, France.
authors.forename: R Leon
authors.initials: RL
authors.lastname: Ochiai
mesh_terms: D000293:Adolescent; D001938:Brazil / Q000453:epidemiology; D002648:Child; D015331:Cohort Studies; D003105:Colombia / Q000453:epidemiology; D003715:Dengue / Q000453:epidemiology* / Q000517:prevention & control; D053059:Dengue Vaccines; D062665:Epidemiological Monitoring; D005260:Female; D006721:Honduras / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008297:Male; D008800:Mexico / Q000453:epidemiology; D011647:Puerto Rico / Q000453:epidemiology; D055815:Young Adult
chemical_list: D053059:Dengue Vaccines
keywords: Dengue; Epidemiology; Flavivirus; South America; Surveillance