Ten-year (1999-2009) epidemiological and virological surveillance of influenza in South Italy (Apulia)

Clinical and epidemiological surveillance of influenza and other Acute Respiratory Infections (ARI) are currently amajor objective of PublicHealth. The aim was to describe the epidemiology of influenza using the Italian surveillance system. Vaccination Coverage (VC) rates were calculated during 1999-2009 influenza seasons. Molecular studies of influenza virus isolated, from patients with ILI, living in Apulia, are described. 1269 nasal-pharyngeal swabs were taken from patients with ILI and ARI in order to isolate and identify viruses using PCR. Influenza isolates are typed as being types A and B and influenza A isolates are A/H1 and A/H3. The progression of the ILI cases registered in Apulia was similar to the data recorded on a national level. The VC data recorded in Apulia showed a progressive increase in the vaccine doses administered to subjects over 65 years old. The virological surveillance showed a major circulation of the type A/H3N2 influenza virus during the peak incidence of the illness in seasons 1999-2000, 2002-2003, 2004-2005 and 2008-2009. During the same period, the lowest incidence was registered when the type A/H1N1 and B viruses were in circulation. In contrast, during the other seasons the lowest incidence was reported with A/H3N2 and B viruses