BackgroundClassical Kaposi’s Sarcoma (cKS) is a rare vascular tumor, which develops in subjects infected with Human Herpesvirus-8 (HHV-8). Beside the host predisposing factors, viral genetic variants might possibly be related to disease development. The aim of this study was to identify HHV-8 variants in patients with cKS or in HHV-8 infected subjects either asymptomatic or with cKS-unrelated cutaneous lymphoproliferative disorders.MethodsThe VR1 and VR2 regions of the ORF K1 sequence were analyzed in samples (peripheral blood and/or lesional tissue) collected between 2000 and 2010 from 27 subjects with HHV-8 infection, established by the presence of anti-HHV-8 antibodies. On the basis of viral genotyping, a phylogenetic analysis and a time-scaled evaluation were performed.ResultsTwo main clades of HHV-8, corresponding to A and C subtypes, were identified. Moreover, for each subtype, two main clusters were found distinctively associated to cKS or non-cKS subjects. Selective pressure analysis showed twelve sites of the K1 coding gene (VR1 and VR2 regions) under positive selective pressure and one site under negative pressure.ConclusionThus, present data suggest that HHV-8 genetic variants may influence the susceptibility to cKS in individuals with HHV-8 infection.

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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.

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Limited information is available on the viral etiology of influenza-like illness in southern European countries, and it is still a matter of debate whether certain symptoms can be used to distinguish among the specific viruses that cause influenza-like illness. The main objective of the present study was to identify the demographic and clinical predictors of influenza-like illness due to specific viral agents. The study, which was observational in design, was conducted in Rome and Naples, Italy. Cases of influenza-like illness were defined as individuals with fever >37.5 degrees C and at least one systemic and one respiratory symptom, recruited during the winters of 2004-2005, 2005-2006, and 2006-2007. Influenza and other respiratory viruses were identified using the polymerase chain reaction (PCR), performed on throat swabs. Basic individual information was collected using a standard form. A total of 580 persons were included in the analysis. Viral pathogens were identified in fewer than 50% of the cases. Overall, 240 viral agents were detected: 22.8% were positive for influenza viruses, 10.9% for adenoviruses, 6.0% for parainfluenza viruses, and 1.7% for respiratory syncytial virus. The month of diagnosis, and muscle and joint pain were associated with influenza virus, though the positive predictive value (PPV) was low. Abdominal pain was associated with adenovirus infection. Although the PPV of symptoms for influenza virus infection was low, especially in low activity periods, these findings may help clinicians to improve their ability to perform diagnoses.