RESUMEN
PROBLEM: The revision of the International Health Regulations (IHR) and the threat of influenza pandemics and other disease outbreaks with a major impact on developing countries have prompted bolstered surveillance capacity, particularly in low-resource settings. APPROACH: Surveillance tools with well-timed, validated data are necessary to strengthen disease surveillance. In 2007 Madagascar implemented a sentinel surveillance system for influenza-like illness (ILI) based on data collected from sentinel general practitioners. SETTING: Before 2007, Madagascar's disease surveillance was based on the passive collection and reporting of data aggregated weekly or monthly. The system did not allow for the early identification of outbreaks or unexpected increases in disease incidence. RELEVANT CHANGES: An innovative case reporting system based on the use of cell phones was launched in March 2007. Encrypted short message service, which costs less than 2 United States dollars per month per health centre, is now being used by sentinel general practitioners for the daily reporting of cases of fever and ILI seen in their practices. To validate the daily data, practitioners also report epidemiological and clinical data (e.g. new febrile patient's sex, age, visit date, symptoms) weekly to the epidemiologists on the research team using special patient forms. LESSONS LEARNT: Madagascar's sentinel ILI surveillance system represents the country's first nationwide "real-time" surveillance system. It has proved the feasibility of improving disease surveillance capacity through innovative systems despite resource constraints. This type of syndromic surveillance can detect unexpected increases in the incidence of ILI and other syndromic illnesses.