title: Tick-borne encephalitis in north-east Italy: a 14-year retrospective study, January 2000 to December 2013.
abstract: Italy is considered at low incidence of tick-borne encephalitis (TBE), and the occurrence of human cases of TBE appears to be geographically restricted to the north east of the country. However, most information to date derives from case series, with no systematic data collection. To estimate incidence rates (IR) and spatial distribution of TBE cases, we conducted a retrospective study in north-eastern Italy. Data were collected through the infectious disease units and public health districts of three regions (Friuli Venezia Giulia, Trentino Alto Adige and Veneto) between 2000 and 2013. Overall, 367 cases were identified (IR: 0.38/100,000). The cases' median age was 56 years and 257 (70%) were male. Central nervous system involvement was reported in 307 cases (84%). Annual fluctuations in case numbers occurred, with peaks in 2006 and in 2013, when 44 and 42 cases were respectively observed. A strong seasonality effect was noted, with the highest number of cases in July. In terms of geographical location, three main endemic foci with high TBE IR (>10/100,000) were identified in three provinces, namely Belluno (Veneto region), Udine (Friuli Venezia Giulia) and Trento (Trentino Alto-Adige). When investigating the whole study area in terms of altitude, the IR between 400 and 600 m was greater (2.41/100,000) than at other altitudes (p<0.01). In conclusion, the incidence of TBE in Italy is relatively low, even considering only the three known affected regions. However, three endemic foci at high risk were identified. In these areas, where the risk of TBEV infection is likely high, more active offer of TBE vaccination could be considered.
authors.affiliation: Department of Infectious, Parasitic and Immunomediated Diseases, National Institute of Health, Rome, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Rezza
authors.forename: Francesca
authors.initials: F
authors.lastname: Farchi
authors.forename: Patrizio
authors.initials: P
authors.lastname: Pezzotti
authors.forename: Maurizio
authors.initials: M
authors.lastname: Ruscio
authors.forename: Alessandra
authors.initials: A
authors.lastname: Lo Presti
authors.forename: Massimo
authors.initials: M
authors.lastname: Ciccozzi
authors.forename: Valeria
authors.initials: V
authors.lastname: Mondardini
authors.forename: Claudio
authors.initials: C
authors.lastname: Paternoster
authors.forename: Matteo
authors.initials: M
authors.lastname: Bassetti
authors.forename: Maria
authors.initials: M
authors.lastname: Merelli
authors.forename: Pier Giorgio
authors.initials: PG
authors.lastname: Scotton
authors.forename: Roberto
authors.initials: R
authors.lastname: Luzzati
authors.forename: Josef
authors.initials: J
authors.lastname: Simeoni
authors.forename: Peter
authors.initials: P
authors.lastname: Mian
authors.forename: Rosanna
authors.initials: R
authors.lastname: Mel
authors.forename: Valter
authors.initials: V
authors.lastname: Carraro
authors.forename: Alessandra
authors.initials: A
authors.lastname: Zanin
authors.forename: Roberto
authors.initials: R
authors.lastname: Ferretto
authors.forename: Ermenegildo
authors.initials: E
authors.lastname: Francavilla
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D004669:Encephalitis Viruses, Tick-Borne / Q000302:isolation & purification*; D004675:Encephalitis, Tick-Borne / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology; D005260:Female; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D018884:Ixodes / Q000821:virology*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000235:genetics; D012189:Retrospective Studies; D012621:Seasons; D017678:Sex Distribution
chemical_list: D012367:RNA, Viral
keywords: Italy; epidemiology; tick-borne encephalitis; tick-borne virus