title: Early-warning health and process indicators for sentinel surveillance in Madagascar 2007-2011.
abstract: BACKGROUND
  Epidemics pose major threats in resource-poor countries, and surveillance tools for their early detection and response are often inadequate. In 2007, a sentinel surveillance system was established in Madagascar, with the aim of rapidly identifying potential epidemics of febrile or diarrhoeal syndromes and issuing alerts. We present the health and process indicators for the five years during which this system was constructed, showing the spatiotemporal trends, early-warning sign detection capability and process evaluation through timely analyses of high-quality data.
  
  
  METHODS
  The Malagasy sentinel surveillance network is currently based on data for fever and diarrhoeal syndromes collected from 34 primary health centres and reported daily via the transmission of short messages from mobile telephones. Data are analysed daily at the Institut Pasteur de Madagascar to make it possible to issue alerts more rapidly, and integrated process indicators (timeliness, data quality) are used to monitor the system.
  
  
  RESULTS
  From 2007 to 2011, 917,798 visits were reported. Febrile syndromes accounted for about 11% of visits annually, but the trends observed differed between years and sentinel sites. From 2007 to 2011, 21 epidemic alerts were confirmed. However, delays in data transmission were observed (88% transmitted within 24 hours in 2008; 67% in 2011) and the percentage of forms transmitted each week for validity control decreased from 99.9% in 2007 to 63.5% in 2011.
  
  
  CONCLUSIONS
  A sentinel surveillance scheme should take into account both epidemiological and process indicators. It must also be governed by the main purpose of the surveillance and by local factors, such as the motivation of healthcare workers and telecommunication infrastructure. Permanent evaluation indicators are required for regular improvement of the system.
authors.affiliation: Unité d'Epidémiologie, Institut Pasteur de Madagascar, Antananarivo, Madagascar.
authors.forename: Soatiana
authors.initials: S
authors.lastname: Rajatonirina
authors.affiliation: Unité d'Epidémiologie, Institut Pasteur de Madagascar, Antananarivo, Madagascar.
authors.forename: Fanjasoa
authors.initials: F
authors.lastname: Rakotomanana
authors.affiliation: Unité d'Epidémiologie, Institut Pasteur de Madagascar, Antananarivo, Madagascar.
authors.forename: Laurence
authors.initials: L
authors.lastname: Randrianasolo
authors.affiliation: Unité de Virologie, Institut Pasteur de Madagascar, Antananarivo, Madagascar.
authors.forename: Norosoa Harline
authors.initials: NH
authors.lastname: Razanajatovo
authors.affiliation: Unité de Virologie, Institut Pasteur de Madagascar, Antananarivo, Madagascar.
authors.forename: Soa Fy
authors.initials: SF
authors.lastname: Andriamandimby
authors.affiliation: Directions des Urgences et de la Lutte contre les Maladies Négligées (DULMN), Ministère de la Santé Publique, Antananarivo, Madagascar.
authors.forename: Lisette
authors.initials: L
authors.lastname: Ravolomanana
authors.affiliation: Direction de la Veille Sanitaire et de la Surveillance Epidémiologique (DVSSE), Ministère de la Santé Publique, Antananarivo, Madagascar.
authors.forename: Armand Eugène
authors.initials: AE
authors.lastname: Randrianarivo-Solofoniaina
authors.affiliation: Unité de Virologie, Institut Pasteur de Madagascar. Present address: Unité de Biologie des Infections Virales Emergentes / Institut Pasteur de Lyon.
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Reynes
authors.affiliation: Unité d'Epidémiologie, Institut Pasteur de Madagascar, Antananarivo, Madagascar.
authors.forename: Patrice
authors.initials: P
authors.lastname: Piola
authors.affiliation: Malaria Branch, Division of Parasitic Diseases US Centers for Disease Control and Prevention, President's Malaria Initiative, Madagascar.
authors.forename: Alyssa
authors.initials: A
authors.lastname: Finlay-Vickers
authors.affiliation: Unité de Virologie, Institut Pasteur de Madagascar, Antananarivo, Madagascar.
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Heraud
authors.affiliation: Unité d'épidémiologie, Institut Pasteur de Dakar, Dakar, Sénégal.
authors.forename: Vincent
authors.initials: V
authors.lastname: Richard
keywords: Madagascar; Sentinel surveillance; early warning; mobile phone