Despite the availability of safe and effective HBV vaccines for more than 30 years, the burden of HBV is still substantial and vaccination delay has been described in several countries with unexpected regional differences. 487 were given birth to after 1981, so they were eligible to have received HBV vaccination in adolescence or at birth; in these subjects antibodies against HBV core antigen experienced the significant prevalence of 6.2%. Universal HBV vaccination has shown evidence of protecting against contamination in the general population. These results, amongst the first to evaluate actual protection in DUs vaccinated at birth or during adolescence, show that compulsory universal vaccination does not solve the problem of HBV transmission in the most at risk groups and that additional strategies must be analyzed and implemented to address this issue. = 0.001) (Table 1). The prevalence of positive HIV serology was 1.3% (10/748 DUs) and positive HCV serology was 19.4% (145/748 DUs). Table 1 Anti-HBcAb seroconversion: univariate analysis. thead th colspan=”2″ rowspan=”2″ align=”center” valign=”middle” Demographic Characteristics /th th colspan=”2″ align=”center” valign=”middle” rowspan=”1″ Anti-HBcAb + /th th AZD3514 rowspan=”2″ align=”center” valign=”middle” colspan=”1″ Odds Ratio /th th AZD3514 rowspan=”2″ align=”center” valign=”middle” colspan=”1″ CI 95% /th th rowspan=”2″ align=”center” valign=”middle” colspan=”1″ em p /em /th th align=”center” valign=”middle” rowspan=”1″ colspan=”1″ No /th th align=”center” valign=”middle” rowspan=”1″ colspan=”1″ Yes /th /thead Total 684 (91.4)64 (8.6) SexFemales213 (89.9)24 (10.1)1 0.296Males471 (92.2)40 (7.8)1.330.78C2.26CitizenshipItalians609 (93.3)44 (6.7)1 0.0001Foreigners75 (78.9)20 (21.1)3.692.05C6.65Birthplace (Italians)North401 (95.3)20 (4.7)1 0.023Center53 (89.8)6 (10.2)2.270.87C5.91South154 (89.5)18 (10.5)2.341.21C4.55Year of Birth (Italians)1981403 Gpc4 (95.7)18 (4.3)1 0.001 1981206 (88.8)26 (11.2)2.831.51C5.27 Open in a separate windows In the group of 653 Italian DUs the prevalence of HBV contamination was 6.7% (44/653 DUs). In those given birth to after 1981, Anti-HBcAb was found in 18/421 (4.3%) subdivided geographically as follows: North13/136 (9.6%), Center 1/18 (5.6%), South 12/78 (15.4%). In the Italian DUs given birth to after 1981, therefore eligible to have received compulsory vaccination, the presence of protective antibodies (Anti-HBsAb), showing that they had been vaccinated, was detectable in 72.1% of the subjects susceptible to have come in contact with HBV (290/402 DUs). 3.1. Univariate Analysis The univariate analysis showed that, foreigners experienced significantly higher prevalence of HBV contamination compared to Italians. Considering Italians only, the probability of being infected was higher for those given birth to in the South compared to those given birth to in the North, and AZD3514 for those given birth to before 1981. 3.2. Multivariate Analysis A multivariate analysis using logistic regression was performed to outline the profile of the Italian seroconverted. The variables used were sex, 12 months of birth and place of birth (North, Center, South) (Table 2). Table 2 Anti-HBcAb seroconversion among Italians: multivariate analysislogistic regression. thead th colspan=”2″ align=”center” valign=”middle” rowspan=”1″ Demographic Characteristics /th th align=”center” valign=”middle” rowspan=”1″ colspan=”1″ Odds Ratio /th th align=”center” valign=”middle” rowspan=”1″ colspan=”1″ CI 95% /th th align=”center” valign=”middle” rowspan=”1″ colspan=”1″ em p /em /th /thead SexFemales1 Males1.510.79C2.900.215Year of Birth19811 19812.801.48C5.310.002Zone of BirthNorth1 Center2.260.86C5.960.099South2.131.09C4.190.028 Open in a separate window 4. AZD3514 Conversation This study found that the prevalence of Anti-HBc positivity among the Italian DUs was shown to be much lower compared to comparable studies conducted in the past decade, confirming the expected decline of HBV even in these subjects, due to the universal immunization programs. The self-evident differences in contact with HBV, shown in this study, between DUs given birth to in Northern Italy, where neonatal vaccination compliance is nearly total (97%, higher than the 88% percent the U.S.A. and 84% in Belgium) [53,54,55,56,57,58,59,60], and those given birth to in the Center-South, with clearly lower vaccination protection, could reflect an effective role played by universal vaccination. Secondly, this study seems to confirm what was recently observed among DUs in Australia, where despite a universal vaccination program that covered AZD3514 90% of the nonadult population, a significant quantity of DUs (17%, theoretically already vaccinated during child years) resulted exposed to contact with HBV [61]. Furthermore, the presence of protected antibodies in our group was significantly lower when compared to that found among students of Padua University or college Medical School (Northern Italy) [62]. Despite the availability of safe and effective HBV vaccines for more than 30 years, the burden of HBV is still substantial and vaccination delay has been explained in several countries with unexpected regional differences. In the 2000?2002 in the US, the three-dose HBV vaccine among children ranged from 49.4% (Vermont) to 81.6% (Rhode Island) [53]. Paradoxically, universal vaccination has led the population of developed countries to feel protected and to believe that HBV is usually no longer a public health issue [31,54]. Thirdly, the finding that only a third of the DUs in our study had been tested for HBV markers is usually worrying. Testing has multiple functions: not only to monitor the phenomena, but also to develop attention in healthcare workers, in DUs and their families towards infective risks linked to the use of illicit drugs [16,28]. The decline in new HIV infections and a drop on the use of the injective route in new DUs, paired with the idea that mass HBV vaccination has finally solved the problem in all the young populace, may have led to this decline in testing, particularly for HBV. In 2011, in Italy, of the.