title: Sentinel surveillance system for early outbreak detection in Madagascar.
abstract: BACKGROUND
  Following the outbreak of chikungunya in the Indian Ocean, the Ministry of Health directed the necessary development of an early outbreak detection system. A disease surveillance team including the Institut Pasteur in Madagascar (IPM) was organized to establish a sentinel syndromic-based surveillance system. The system, which was set up in March 2007, transmits patient data on a daily basis from the various voluntary general practitioners throughout the six provinces of the country to the IPM. We describe the challenges and steps involved in developing a sentinel surveillance system and the well-timed information it provides for improving public health decision-making.
  
  
  METHODS
  Surveillance was based on data collected from sentinel general practitioners (SGP). The SGPs report the sex, age, visit date and time, and symptoms of each new patient weekly, using forms addressed to the management team. However, the system is original in that SGPs also report data at least once a day, from Monday to Friday (number of fever cases, rapid test confirmed malaria, influenza, arboviral syndromes or diarrhoeal disease), by cellular telephone (encrypted message SMS). Information can also be validated by the management team, by mobile phone. This data transmission costs 120 ariary per day, less than US$1 per month.
  
  
  RESULTS
  In 2008, the sentinel surveillance system included 13 health centers, and identified 5 outbreaks. Of the 218,849 visits to SGPs, 12.2% were related to fever syndromes. Of these 26,669 fever cases, 12.3% were related to Dengue-like fever, 11.1% to Influenza-like illness and 9.7% to malaria cases confirmed by a specific rapid diagnostic test.
  
  
  CONCLUSIONS
  The sentinel surveillance system represents the first nationwide real-time-like surveillance system ever established in Madagascar. Our findings should encourage other African countries to develop their own syndromic surveillance systems.Prompt detection of an outbreak of infectious disease may lead to control measures that limit its impact and help prevent future outbreaks.
authors.affiliation: Unité d'Epidémiologie, Institut Pasteur de Madagascar, Antananarivo, République de Madagascar.
authors.forename: Laurence
authors.initials: L
authors.lastname: Randrianasolo
authors.forename: Yolande
authors.initials: Y
authors.lastname: Raoelina
authors.forename: Maherisoa
authors.initials: M
authors.lastname: Ratsitorahina
authors.forename: Lisette
authors.initials: L
authors.lastname: Ravolomanana
authors.forename: Soa
authors.initials: S
authors.lastname: Andriamandimby
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Heraud
authors.forename: Fanjasoa
authors.initials: F
authors.lastname: Rakotomanana
authors.forename: Robinson
authors.initials: R
authors.lastname: Ramanjato
authors.forename: Armand Eugène
authors.initials: AE
authors.lastname: Randrianarivo-Solofoniaina
authors.forename: Vincent
authors.initials: V
authors.lastname: Richard
mesh_terms: D000293:Adolescent; D000328:Adult; D018354:Alphavirus Infections / Q000175:diagnosis / Q000453:epidemiology*; D002646:Chikungunya virus; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks / Q000517:prevention & control*; D005334:Fever / Q000209:etiology; D006801:Humans; D007223:Infant; D008270:Madagascar / Q000453:epidemiology; D012308:Risk Management; D018571:Sentinel Surveillance; D017678:Sex Distribution