[Tuberculosis surveillance in Sicily, Italy].

OBJECTIVE

To describe the epidemiology of tuberculosis (TB) in Sicily in the years 2010-2013.

DESIGN AND PARTICIPANTS

Observational study of the TB notifications in the years 2010-2013 by analyzing the Sistema informative delle malattie infettive (SIMI) database and carrying out a molecular epidemiological analysis by spoligo- e 24-loci mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) typing of the Mycobacterium tuberculosis complex (MTBC) isolates identified in Palermo, Italy, in the years 2012-2013.

RESULTS

In the four-year period under study 876 TB cases were notified in Sicily with a mean annual notification rate of 4.4 cases per 100,000 inhabitants. The proportion of TB cases in the foreign-born individuals was increasing and higher than the proportion in Italian-born in the period 2010-2013. The median age of foreign-born patients was significantly lower than the Italian-born (30.5 vs. 51.2 years, p <0,001). Moreover, the distribution by age class was also significantly different, with the largest proportion of TB cases among the foreign-born sub-population in the 15-44 age class, whereas the Italian-born cases were equally distributed in the 15-44, 45-64 and >64 age classes. Eighty-two percent of cases were pulmonary TB. Molecular typing of 151 MTBC isolates identified in Palermo in 2012 and 2013 detected14 lineages and 33 subline ages showing a different distribution among the two patients sub-populations. Only nine MTBC isolates (6.2%) were grouped in four clusters. Two multidrug resistant (MDR) MTBC isolates were identified from an Italian born elderly patient and an Eritrean young patient (Beijing lineage), respectively.

CONCLUSIONS

TB epidemiology in Sicily is complex and is rapidly changing. The most striking features are the increasing proportion of cases in the foreign-born population and the wide heterogeneity of MTBC isolates. An integrated approach using both conventional and molecular tools is necessary to accurately assess and monitor TB epidemiology in this Region.