Syndrome surveillance and molecular epidemiology for early detection and tracing of an outbreak of measles in Liguria, Italy

Abstract

The performances of surveillance systems for measles in Europe are poorly investigated, despite the fundamental role they should play in the early detection of outbreaks and in the assessment of the progress towards elimination. A new chief complaint syndrome surveillance system has been developed in Genoa, Italy, using data from the Emergency Department records of the regional reference university hospital and its ability to early detect an outbreak of measles that began during the winter months of 2007/2008 was evaluated. For the 23-month period from January 2007 to November 2008, the Emergency Department registration and triage software was used to obtain the time series of daily counts, that were related with cases notified by the statutory notification system and detection and characterization data from the measles regional reference laboratory. One hundred fifty five cases of measles-like illness were identified by the syndrome surveillance system. Two epidemic threshold breakthroughs were able to anticipate the first notified case by 54 and 11 days. Globally, the new syndrome surveillance system allows the activation of the alert state with a specificity of 94.3% and a sensitivity of 91%. Molecular investigation showed the spread of the virus from United Kingdom to Piemonte and then to Liguria and allowed us to exclude the re- circulation of strains circulating in Northern Italy during the previous seasons. Syndrome surveillance integrated with a rapid detection and characterization of the agent responsible for the disease could be an effective, specific and sensitive tool for measles surveillance.

Epidemiological and molecular assessment of a rubella outbreak in North‐Eastern Italy

“…Otherwise, genotype 2B may have been imported, either from countries where this virus was circulating or from the United Kingdom where the genotype had been endemic since 2006. An interchange between Italy and the United Kingdom has been demonstrated for rubella virus as well as for measles virus [Ansaldi et al, 2009].…”

Success Factors of European Syndromic Surveillance Systems: A Worked Example of Applying Qualitative Comparative Analysis

“…No results from subnational analysis were reported, but from analysis by age group. The syndromic surveillance system in Genoa monitored two measles outbreaks with a timeliness of -3.57 weeks on average based on acute care data [ 33 , 34 ]. In this case, subnational surveillance was applied in one study and was connected to a 1.43 week advance detection [ 34 ].…”

Potential effect of PCV13 introduction on Emergency Department accesses for lower respiratory tract infections in elderly and at risk adults

“…22,23 The comparison of LRTI incidence obtained from different studies is difficult because of heterogeneity of study design, database and case definitions used. The criteria for confirmation of captured cases used in this study allowed to exclude accesses for acute bronchitis and a revision of a subset of confirmed cases (data not shown) showed that almost all cases fit the case definition of CAP proposed by expert.…”

“…The Surveillance System is coordinated by a reference centre (University of Genoa). Syndrome coding, data capture, transmission and processing, statistical analysis to assess indicators of disease activity and alert thresholds, and signal response were operatively described in Ansaldi et al 22,36 The study population consisted of adult subjects (≥ 18-y-old) resident in Genoa, a city of 650,000 inhabitants and capital of Liguria, an administrative region in Northern Italy. The surveyed period covered 3 seasons (2010/2011, 2011/2012, 2012/2013).…”