Evaluation of a vaccination strategy by serosurveillance data: The case of varicella

Serological studies have many important epidemiologic applications. They can be used to investigate acquisition of various infections in different populations, measure the induction of an immune response in the host, evaluate the persistence of antibody, identify appropriate target groups and the age for vaccination. Serological studies can also be used to determine the vaccine efficacy. Since 1995 a varicella vaccine is available and it has been recommended in several countries (e.g. USA, Australia, Canada, Costa Rica, Ecuador, etc.). Nevertheless few varicella seroprevalence studies in countries that adopted an URV are available. It is related to the relatively recent introduction of the vaccination and to the lack of structured and collaborative surveillance systems based on serosurvey at national or regional level. Varicella seroprevalence data collected before the introduction of vaccination strategies allowed to establish the age of vaccination (e.g., indicated the opportunity to offer the vaccine to Italian susceptible adolescents). In the post-vaccination era, seroprevalence data demonstrated vaccine as immunogenic and excluded an increase of the age of infection linked to the vaccination strategy. New seroprevalence studies should be performed to answer to open questions, such as the long-term immunity and the change of the herpes zoster epidemiological pattern related to the vaccine

Serosurveillance of hepatitis A in a region which adopted the universal mass vaccination

Hepatitis A is a common infectious disease worldwide that was endemic in many regions of Southern Italy, such as Apulia region. After a large hepatitis A outbreak occurred between 1996 and 1997, in Apulia an active-free immunization program that was targeted to new-borns and adolescents was started. The aim of this study is to investigate the hepatitis A seroprevalence in the adult Apulian population 18 years after the immunization program introduction, in order to evaluate the risk of new epidemics onset.The study was carried out from May 2011 to June 2012 among blood donors from Department of Transfusion Medicine and Blood Bank of Policlinico General Hospital in Bari. Participants signed a written consent and filled out a questionnaire including items on demographic characteristics, risk factors, disease memory, and raw food consumption. Serum samples, collected from each patient, were tested for anti-HAV using the chemiluminescent microparticle immunoassay. Vaccination status against hepatitis A was checked on Regional Digital Immunization Registry (GIAVA).In total 1827 donors agreed to participate (77.7% male) with a mean age of 38.4 ± 11.7 years. However, 1172 (64.1%) donors were seropositive with no difference by sex. The highest proportion of seronegative subjects was in the 27 to 35 years age group. 91.8% of 1-dose vaccinated subjects (n = 190/207; 95%CI = 87.2-95.1) and 96.1% (n = 171/178; 95%CI = 92.1-98.1) of 2-doses vaccinated subjects were immune to the disease. Sensitivity of disease memory in unvaccinated subjects was 14.4% (95%CI = 12.2-16.7), specificity was 97.8% (95%CI = 96.3-98.8), positive predictive value was 91% (95%CI = 85.3-95), and negative predictive value was 42.6% (95%CI = 40-45.2). Raw seafood consumption in unvaccinated subjects was associated with the anti-HAV IgG positivity (OR = 2.1; 95%CI = 1.7-2.7; z = 7.4; P < 0.0001).The vaccination program seems to have changed the virus circulation pattern, with a higher seronegativity rate among subjects not included in the vaccination strategy: 67% of susceptible subjects were among younger people aged 27 to 35 years. Immunization program implementation with a catch-up strategy may be needed to avoid a possible increase of hepatitis A incidence and outbreaks in Apulia. Epidemiological surveillance should be continued and vaccination should actively be offer for free to all the cases contacts, in order to prevent new outbreaks onset

Women and alcohol. A survey in the city of Barletta

Introduction. The aim of this survey was to evaluate the qualitative and quantitative relationship among women from Barletta - a national renowned wine center - and their alcohol consumption. Methods. The AUDIT questionnaire was used to assess the prevalence of alcohol hazardous consumption among women. Questionnaires were submitted from March to November 2012. The sample was composed of 150 women older than 13 years of age, selected by stratified sampling based on age group. Results. 107 women were enrolled with a total response rate of 71.3%. 62% of enrolled women consumes alcoholic beverages with a frequency that goes from 2-3 times a week to less than once a month, usually 1 or 2 alcoholic units. The binge-drinking was reported by 5% of women. Women who reported alcohol-related risk behaviors were less than 3%, they were single and between 18 and 60 years old and such behaviors occur less than once a month. The final score, calculated for all the women from their questionnaire answers, was not higher than 8, with an average score of 1.3 (SD = 1.5; range: 0 to 2.8). The comparison of the average scores of the three age groups showed a statistically sig- nificant difference (F = 5.8, p = 0.004). Discussion. Data from literature showed a change in the habits of alcohol intake by the global, European and also Italian population. These changes also affect and involve female. Our study found a quite moderate alcohol consumption among women from Barletta, with only 1% who consumes 3 or more alcohol units and drink more than four times a week and 3% who had hazardous behavior related to their alcohol consumption. Statistical significance was found for the age and the lack of stable relationships. The analysis of characteristics of at risk women (old age and single-status) suggests that much attention should be paid to them and they should represent the main subject of future social interventions to prevent alcohol related problems in the city of Barletta

Acute Delta Hepatitis in Italy spanning three decades (1991–2019): Evidence for the effectiveness of the hepatitis B vaccination campaign

Updated incidence data of acute Delta virus hepatitis (HDV) are lacking worldwide. Our aim was to evaluate incidence of and risk factors for acute HDV in Italy after the introduction of the compulsory vaccination against hepatitis B virus (HBV) in 1991. Data were obtained from the National Surveillance System of acute viral hepatitis (SEIEVA). Independent predictors of HDV were assessed by logistic-regression analysis. The incidence of acute HDV per 1-million population declined from 3.2 cases in 1987 to 0.04 in 2019, parallel to that of acute HBV per 100,000 from 10.0 to 0.39 cases during the same period. The median age of cases increased from 27 years in the decade 1991-1999 to 44 years in the decade 2010-2019 (p < .001). Over the same period, the male/female ratio decreased from 3.8 to 2.1, the proportion of coinfections increased from 55% to 75% (p = .003) and that of HBsAg positive acute hepatitis tested for by IgM anti-HDV linearly decreased from 50.1% to 34.1% (p < .001). People born abroad accounted for 24.6% of cases in 2004-2010 and 32.1% in 2011-2019. In the period 2010-2019, risky sexual behaviour (O.R. 4.2; 95%CI: 1.4-12.8) was the sole independent predictor of acute HDV; conversely intravenous drug use was no longer associated (O.R. 1.25; 95%CI: 0.15-10.22) with this. In conclusion, HBV vaccination was an effective measure to control acute HDV. Intravenous drug use is no longer an efficient mode of HDV spread. Testing for IgM-anti HDV is a grey area requiring alert. Acute HDV in foreigners should be monitored in the years to come

Erratum: Lack of immunity against rubella among Italian young adults. [BMC Infect Dis., 17, (2017) (199)] Doi: 10.1186/s12879-017-2295-y

After publication of this article [1], the authors noted that the given names and family names of all authors had been inverted, and are therefore incorrect in the original article. In the original article, the author names appear as the following: Gallone Maria Serena, Gallone Maria Filomena, Larocca Angela Maria Vittoria, Germinario Cinzia and Tafuri Silvio. However, this is incorrect, and the author names should appear as per the below: Maria Serena Gallone, Maria Filomena Gallone, Angela Maria Vittoria Larocca, Cinzia Germinario, Silvio Tafuri. The author names have been corrected in the author list and the citation for this Erratum

Monitoring the process of measles elimination by serosurveillance data: The Apulian 2012 study

In 2003 Italy adopted the National Plan for Measles and Congenital Rubella Elimination, but some outbreaks of measles are still occurring, as the target coverage rate (≥95%) for new-borns has currently not been achieved. In order to support the monitoring of the measles elimination programme, the authors carried out a survey about the seroprevalence of measles among Apulia young adults. The study was carried out from May 2011 to June 2012 among blood donors of the Department of Transfusion Medicine of Policlinico General Hospital in Bari. Subjects were enrolled by a convenience sampling. For each enrolled patient we collected a 5mL serum sample. Collected sera were tested by chemiluminescence (CLIA) for anti-Measles IgG. We enrolled 1764 subjects; 1362 (77.2%) were male with a mean age of 38.4±11.7 years. Anti-Measles IgG titre was >16.5UA/mL in 95.1% (95% CI=94.1-96.1) of enrolled subjects with a Geometric Mean Titre (GMT) of 2.3±0.4, which did not differ dividing the enrolled subjects into age groups. As our data showed, the universal routine vaccination changed the epidemiological pattern among adults, in particular young adults (18-24 years), who showed lowest seropositivity rates; in these groups of population there is a risk of the onset of outbreaks due to the presence of susceptible population. This is a paradox linked to the vaccination strategy: when coverage rates keep sub-optimal, measles is more likely to affect young adults and a higher percentage of complications is expected. According to our data, health authorities have to plan a mop-up strategy to actively offer measles vaccination to susceptible young adults

Medical students' attitude toward influenza vaccination: Results of a survey in the University of Bari (Italy)

Influenza vaccination is strongly recommended for Italian healthcare professionals, but vaccine coverage is low. Since 2012, vaccination is also offered to medical students as part of the National Immunization Plan; however, few Medical Schools has implemented the plan so far. To study determinants of vaccination compliance, we conducted a survey among medical students at the University of Bari, where influenza vaccination has been actively offered since 2013. Information was obtained by means of an online anonymous questionnaire administered in April 2014. We enrolled 669 students, 383 (57%) vaccinated; 54% were female and the average age was 23.9 ± 4.9 y. Determinants of getting vaccinated were analyzed in a multivariate logistic model. Receiving invitation from the University (aOR = 3.8; 95%CI = 1.2-12.3; p = 0.026), the opinion that vaccine is safe (aOR = 2.8; 95%CI = 1.5-5.0; p = 0.001) and useful (aOR = 3.4; 95%CI = 1.7-6.7; p<0.0001), a specific training about influenza vaccination during the course (aOR = 1.5; 95%CI = 1.1-2.1; p = 0.043), and considering himself as at a major risk of influenza complication (aOR = 1.8; 95% CI = 1.1-2.9; p = 0.001) were significantly associated with vaccine acceptance. Active invitation and training are confirmed as key actions (as in children vaccination strategies) and, according to our results, they could be routinely used to promote vaccination in hard-to-reach groups such as healthcare workers

HBV seroprevalence after 25 years of universal mass vaccination and management of non-responders to the anti-Hepatitis B vaccine: an Italian study among medical students

According to international guidelines, healthcare workers and medical students immunized against HBV are periodically tested for anti-HBs IgG. Subjects who show an anti-HBs titer <10 mUI/ml must receive additional vaccine doses to induce a measurable antibody response. This study aimed to evaluate the long-time immunogenicity of anti-hepatitis B vaccination in a sample of medical students and residents of the University of Bari who attended the Hygiene Department for biological risk assessment (April 2014 - June 2017). The strategy for the management of non-responder subjects was evaluated. 3,676 students and residents were invited for testing according to a standardized protocol. Anti-HBs IgG was tested for in 3,140 (85.4%) subjects: 1,174/3,140 (37.7%) subjects were negative. 14.6% (128/808) of subjects who received the vaccine during their 12th year of life and 45.8% (1,056/2,305) ofsubjects immunized during the first year of life (p<0.0001) were negative. 1,005/1,174 (85.6%) seronegative subjects received a booster dose and 903/1,005 (89.9%) were tested for anti-HBs one month after the booster dose: 82/903 (9.1%) subjects were still negative. Of these, 56/82 (68.3%) received two additional doses of vaccine and 52/56 (92.9%) were tested one month after the third dose: 50/52 subjects (96.2%) developed a positive titer. In conclusion, several medical students, immunized at birth or at young age against HBV, did not develop protective titers against the virus. Our management strategy (booster- re-test; for negative subjects, two doses and re-test) seems consistent with the purpose of evidencing immunological memory. This article is protected by copyright. All rights reserved