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Background: This study aimed to determine the prevalence and factors associated with susceptibility to hepatitis B virus (HBV) among cisgender men who have sex with men (MSM) on HIV pre-exposure prophylaxis (PrEP) in Northeastern Brazil., Methods: This was a cross-sectional, analytical study conducted between September 2021 and June 2023. Participants underwent structured interviews to collect sociodemographic and clinical information, including hepatitis B vaccination history, HIV PrEP use and sexual health history. Blood samples were collected for hepatitis B serologic testing: HBV surface antigen (HBsAg), HBV surface antibody (anti-HBs), total and IgM HBV core antibody (anti-HBc). HBV susceptibility was defined as nonreactive results for all these serological markers., Results: A total of 287 participants were enrolled into the study. The median age of the individuals was 31 years (interquartile range: 27; 36). HBV susceptibility was found in 58 out 286 individuals (20.3%; 95% CI: 15.9-25.2). Seventy-six percent of the participants reported completing the three-dose hepatitis B vaccine schedule. Susceptibility was significantly associated with a monthly income ≤ 5 minimum wages (PR: 2.02; 95% CI: 1.01-4.05), lack of complete hepatitis B vaccination schedule (PR: 4.52; 95% CI: 2.89-7.06), initiation of HIV PrEP (PR: 2.18; 95% CI: 1.21-3.94), duration of six months of HIV PrEP (PR: 2.16; 95% CI: 1.19-3.91), absence of tattoos (PR: 1.55; 95% CI: 1.00-2.40) and no history of sexually transmitted infections (PR: 1.65; 95% CI: 1.07-2.54)., Conclusion: Our findings highlight the significant burden of HBV susceptibility among MSM on HIV PrEP in Northeastern Brazil. Socioeconomic factors, vaccination status, PrEP use and sexual health behaviors play critical roles in determining susceptibility to HBV. Integrating hepatitis B screening and vaccination into PrEP services is critical for identifying and addressing HBV susceptibility among MSM. Interventions aimed at increasing vaccination coverage and promoting safer sexual practices are essential for mitigating the burden of HBV infection in this population., (© 2024. The Author(s).)

Background: Despite completion of the vaccine schedule for hepatitis B virus (HBV), children may display levels of HBV surface antibodies (anti-HBs) that are considered inadequate for sufficient protection (<10 IU/L)., Aims: Our aim was to investigate if age and gap time between HBV vaccine doses may negatively affect the levels of anti-HBs in children, and if these relationships are modified by sex., Methods: In a high-endemic HBV region of the western Brazilian Amazon we enrolled children who had completed the HBV vaccine schedule. All children underwent analysis of anti-HBs and a clinical examination., Results: We included 522 children (mean age 4.3 ± 0.8 years; 50% male). Median anti-HBs was 28.4 [interquartile range (IQR) 5.4 to 128.6] IU/L and 32% had anti-HBs <10 IU/L. The median gap time from last to preceding dose was 2.4 [IQR 2.1 to 3.3] months. Levels of anti-HBs decreased with higher age (-42% per year increase [95%CI -56% to -24%], p<0.001), but not with longer gap time (+23% per month increase [95%CI -16% to +62%], p = 0.249). After adjusting for relevant confounders, gap time became significant (p = 0.032) and age remained a significant predictor of anti-HBs (p<0.001)., Conclusion: One third of assessed children displayed anti-HBs <10 IU/L. Levels of anti-HBs decreased with higher age and increased with longer gap time between the last two doses., Competing Interests: The authors have declared that no competing interests exist.

Objective: This article analyzes the effectiveness of a super-accelerated immunization schedule against hepatitis B in patients who have received a liver transplantation., Methods: This is a quantitative and retrospective study based on secondary data of medical records from 177 patients who have received a liver transplantation at the Hospital de Base in São José do Rio Preto, São Paulo State, Brazil, between 1998 and 2016., Results: From the total number of participants, 72.89% were male, 39.55% had a cirrhosis diagnosis with associated causes, 23.16% had hepatocellular carcinoma, 53.11% were classified according to Child-Turcotte-Pugh C score, 58.76% had the hepatitis C virus, 97.18% had received an unconventional immunization schedule, and seroconversion was 36.63% among those with an unconventional schedule. The fact that the patient had the hepatitis C virus was statistically significant considering the lack of protection of the vaccine against the hepatitis B virus; their chances were 5 times higher of not seroconverting at the end of the immunization schedule., Conclusion: The need for high immediate protection in a short term may justify using unconventional immunization schedules in patients who make it to the transplantation waiting list without any previous immunization., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objective: to investigate dental auxiliaries (DA) hepatitis B immunization in Brazilian National Health System (SUS) services in nine cities in São Paulo State, Brazil, in 2018., Methods: this was a cross-sectional study based on interviews using a questionnaire as well as evaluation of immunity using the anti-HBs test, evaluation of prior testing, test result and interpretation and guidance provided about hepatitis B., Results: of the 70 registered DA, 35 completed the course of vaccinations, 29 had negative anti-HBs test results, 16 had tested previously, and 43 did not correctly understand their result; there was association (p=0.025) between completed course of vaccinations and receipt of guidance., Conclusion: most DA received guidance about hepatitis B; however, a considerable portion did not complete the course of vaccinations and had negative anti-HBs test results; few DA had tested previously nor correctly interpreted the result; evidence was found of an alarming scenario in which there are severe shortcomings in DA hepatitis B immunization.

Objectives: To evaluate the epidemiological and molecular features of HBV infection among recyclable waste collectors., Methods: The participants were recruited from the dumping ground and recycling cooperatives in Campo Grande, Brazil, and were screened for hepatitis B and C, and HIV serological markers by ELISA, confirmed by PCR., Results: Among 278 participants, 63.7% (95% CI: 58.0-69.3) were considered susceptible to HBV infection. The prevalence rate of HBV exposure was 10.1% (95% CI: 6.5-13.6) and 0.4% (95% CI: 0.1-0.6) were chronic carriers. Age ≥45 years (AOR=7.15), history of homosexual contact (AOR=5.29), tattoo (AOR=4.92) and history of surgery (AOR=2.89) were factors associated with ever infection. Age 18-25 years (AOR=4.63), educational level ≥9 years (AOR=1.98) and knowledge about HBV transmission (AOR=3.08) were associated with serological HBV vaccination like profile (26.2%; 95% CI: 21.1-31.4)., Conclusions: Despite the availability and efficacy of HBV vaccine, this study found high HBV exposure and proportion of susceptible adults in a low endemic area. Vaccination and screening campaigns using accessible language to the economically disadvantaged populations can reduce the number of people susceptible to HBV infection., (Copyright © 2019 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objective: to describe the occurrence of hepatitis B among pregnant women, immunoprophylaxis and vertical and perinatal transmission in children exposed to the virus in the São Paulo state primary care network, Brazil., Methods: this was a cross-sectional study using prenatal records of pregnant women attending health services between January and June 2012 and a cohort of newborns; the frequencies of the results were described and the estimated occurrence of hepatitis B was calculated., Results: 6,233 pregnant women were included, of whom 53.1% were between 20-29 years old, 58.7% had 8-11 years of schooling, 53.3% were white, and 73.9% lived with a partner; occurrence of hepatitis B was 0.13% (95%CI 0.04; 0.21); of the eight children of mothers with chronic hepatitis B, six had a complete vaccination schedule, and there was no vertical or perinatal transmission., Conclusion: there was low occurrence of hepatitis B in pregnant women and absence of vertical or perinatal transmission.

Viral hepatitis is caused by different etiological agents with distinct epidemiological, clinical, and laboratory characteristics accounting for significant worldwide morbidity and mortality. Since 1996, the Brazilian Department of Sexually Transmitted Infections (STIs), Acquired Immune Deficiency Syndrome (AIDS) and Viral Hepatitis (DIAHV) in collaboration with the Ministry of Defense has been conducting periodic serosurveys of conscripts enlisted for the Brazilian army to assess STI prevalence and obtain data on knowledge and risk factors pertaining to STIs. This article aims to present the hepatitis B (hepatitis B surface antigen - HBsAg) and C (anti-HCV) seroprevalence estimates and risk factors as per the 8th edition of the Conscript Survey performed in 2016.This cross-sectional study was conducted among conscripts across Brazil aged 17 to 22 years from August to December 2016. It included a self-reported questionnaire and blood testing for syphilis, human immunodeficiency virus (HIV), and hepatitis B and C.In total 38,247 conscripts were enrolled; after applying exclusion criteria, 37,282 conscripts were included. The estimated HBsAg and anti-HCV prevalence rates were 0.22% and 0.28%, respectively. Higher HBsAg and anti-HCV prevalence rates were observed in the North Region (0.49%) and in the Central-west Region (0.65%), respectively. Regarding hepatitis B vaccination, 23.5% (n = 8412) of the individuals reported being unvaccinated and 47.4% (n = 16,970) did not know if they had been vaccinated. Among the anti-HCV positive conscripts, 53% (n = 51, 0.56%, P = .049) reported that they had never had sexual intercourse. Regarding self-reported STI status, most of the positive anti-HCV (n = 100, 0.29%, P < .01) and positive HBsAg (n = 76, 0.22%, P = .205) conscripts reported not having a STI. From those who tested positive for HBsAg, 89% (n = 42, 0.28%, P = .005) reported not making consistent use of condoms with steady partners.Our data suggest a low prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among Brazilian young men, and relatively low rates of self-reported HBV immunization. History of STIs, higher number of partners, inconsistent use of condoms, and lack of awareness of routes of transmission were significantly associated with HBV and HCV infections. To achieve the World Health Organization's goal of viral hepatitis elimination, access to hepatitis information, testing, and surveillance need to be improved.

Introduction: Occupational exposure is a major risk factor for hepatitis B (HB) transmission., Methods: Vaccination coverage and immunity verification from 64 dentists of the Brazilian Unified Health System were investigated. An immunochromatographic method was used to verify immunity against the disease., Results: Overall, 77.77% of participating dentists completed the vaccination schedule; 37.50% had negative anti-HBs test results. Furthermore, 60.93% of participants never underwent anti-HBs tests and 40% did not know how to correctly interpret results., Conclusions: Numerous dentists were not immune to the disease. Few participants previously performed the test, with many not knowing how to interpret the results.

Background: The objective of the present study was to analyze the factors associated with non-completion of the hepatitis B vaccine series among men who have sex with men and use geosocial dating apps in Brazil., Methods: This was a cross-sectional, population survey-based, analytical study, conducted exclusively online in all the regions of Brazil, with a sample of 1855 men who have sex with men. The data was collected between November 2016 and February 2017, using the social networking website Facebook., Results: Univariate, bivariate and multivariate analyses showed that 4.7% of the participants reported receiving one dose of the vaccine, 12.5% two doses, 19.4% three doses, and 45.8% did not know. Multivariate analysis showed that level of education (OR = 0.31; CI 95% 0.14-0.72; p = 0.007), identification as bisexual (OR = 0.6; CI 95% 0.38-0.95; p = 0.030), HIV serological status (OR:2.3; CI 95% 1.58-3.34; p = < 0.001) and frequency of access to health services (OR = 2.38; CI 95% 1.53-3.72; p = < 0.001) were associated with not completing the vaccine series. Low completion of the hepatitis B vaccine series was detected in the population studied., Conclusion: Completion of the hepatitis B vaccine series was low among men who have sex with men and use geosocial dating apps in Brazil. The factors associated with non-completion were related to social, individual and healthcare (programmatic) vulnerabilities.

Frequent contact with hazardous materials makes waste collection a potentially unhealthy activity. This article assesses the perception of waste management workers regarding work-related accidents in domestic and health service contexts in Brazil. Six focus groups were performed between June 2014 and August 2015. The aims of this study were to apprehend different aspects of the participants' health, workers' experiences of work-related accidents and perception of risks. Cuts and puncture injuries were reported most frequently in the line of work and were often considered as irrelevant. Immunization against hepatitis B was not common among all workers, which increases the risk of infection for those individuals. Finally, it is considered urgent to consolidate an inclusive space in which workers can have discussions on their health.

Although not directly responsible for patient care, hospital housekeepers are still susceptible to accidents with biological material. The objectives of this study were to establish profile and frequency of accidents among hospital housekeepers, describe behaviors pre- and postaccident, and risk factors. This was a cross-sectional study with hospital housekeepers in Goiania, Brazil. Data were obtained from interviews and vaccination records. The observations were as follows: (1) participating workers: 94.3%; (2) incomplete hepatitis B vaccination: 1 in 3; and (3) accident rate: 26.5%, mostly percutaneous with hypodermic needles, and involved blood from an unknown source; roughly half occurred during waste management. Upon review, length of service less than 5 years, completed hepatitis B vaccination, and had been tested for anti-HBs (hepatitis B surface antigen) influenced frequency of accidents. These findings suggest that improper disposal of waste appears to enhance the risk to hospital housekeepers. All hospital workers should receive continued training with regard to waste management.

Evidence-based strategies to improve the hepatitis B virus (HBV) vaccination coverage rates might help to reduce the burden caused by co-infection with HBV and human immunodeficiency virus (HIV). In this study, the aim was to evaluate the vaccination coverage and immunity against HBV among HIV-infected individuals in South Brazil, and identify factors that are associated with compliance patterns and antibody reactivity. Three hundred HIV-infected men and women were included in this survey. The patients answered a standardized questionnaire, and vaccination cards were checked in order to assess hepatitis B vaccine status. A blood sample was collected for quantitative determination of antibody to hepatitis B virus surface antigen (anti-HBs). Participants were also evaluated for their CD4 cell count and HIV viral load. The overall vaccination coverage of HBV vaccination found in this study (57.4%) was lower than that was previously reported in South Brazil. Anti-HBs levels >10IU/L were observed in 47.0% of the studied population. A significant inequality in the coverage rates and antibody reactivity was found in favor of patients with better economic status. In conclusion, the results indicate the need for improvement in the HBV vaccination coverage among HIV carriers, in particular focusing on low-income individuals., (Copyright © 2015 Elsevier Editora Ltda. All rights reserved.)

The aim of this cross-sectional study was to determine the hepatitis B vaccination coverage among medical students at a public university in Rio de Janeiro, Brazil, and their compliance with the postvaccination serologic testing recommendations. Of the total of 858 students, 675 (78.7%) participated in the study. Among the participants, 48.9% (95% CI: 45.1% to 52.7%) were vaccinated against hepatitis B (received ≥ 3 doses of the vaccine), 31.6% were not (received 0, 1 or 2 doses), and 19.6% did not know their vaccination status. Hepatitis B vaccination coverage increased from 26.0% among first-year students to 70.6% among sixth-year students while the prevalence of unknown vaccination status decreased from 39.7% among first-year students to 2.4% among sixth-year students. The frequency of unvaccinated students ranged from 23.7% among fifth-year students to 34.4% among first-year students. Only 34.8% of the vaccinated students performed the anti-HBs testing after vaccination. Among these medical students, we found a low adherence to the hepatitis B vaccination and to the postvaccination serologic testing. A comprehensive hepatitis B immunization program should be offered to students at this medical school.

Background: It has been reported that vaccination against hepatitis B is less effective among people with Down syndrome than in the general population. We aimed to evaluate the rate of seroconversion to hepatitis B vaccine in children with Down syndrome from Brazil., Methods: A total of 120 people with Down syndrome were included. All of them received the vaccine at intervals of 0, 30 and 180 days and serum samples were tested for the presence of antibodies to the hepatitis B surface antigen (anti-HBs) 30 days after the last dose., Results: In the studied group, 58.3% (70/120) were male and 41.7% (50/120) female, with the median age of 5 years (range 2-15 years). Fifty-eight of 120 (48.3%) developed anti-HBs after vaccination. No association was found between gender and/or age and vaccine response., Conclusions: The low rate of seroconversion in response to hepatitis B vaccine suggests that all patients with Down syndrome immunized against hepatitis B should be followed and monitored by clinicians., (© 2013 John Wiley & Sons Ltd.)

Background: Nursing children are exposed to dietary aluminum (in breast milk and/or infant formulas) and through aluminum-adjuvanted vaccines (AAVs). We studied total hair-Al concentrations of nursing children that had been immunized with hepatitis B, DTP, and meningococcal vaccines., Methods: We studied the hair of 37 young children (aged 26 to 824 days) who were exposed to cumulative doses of Al ranging from 0.63 to 6.88 mg from AAVs. Graphite furnace atomic absorption spectrometry was used to reliably measure total Al concentrations in hair samples., Results: The analytical method proved sensitive enough to quantify Al in the hair of nursing children. At current levels of exposure it is possible to determine total Al in hair sample of 1.65 mg. Cumulative doses of AAV in children ranged from 0.63 to 6.88 mg Al. Median hair-Al was 47.7 μg g⁻¹ (ranging from 12.2 to 221.9 μg g⁻¹). There was no statistically significant correlation between hair-Al concentration and age of child (r=-0.049; p=0.774), total exposure from vaccine (r=-0.078; p=0.643), or the time elapsed after the last AAVs (r=0.015; p=0.931)., Conclusion: Aluminum in children's hair can be reliably measured but we are still uncertain how representative it can be of the Al body burden., (© 2013 Elsevier B.V. All rights reserved.)

Objectives: Describing rates of seroconversion and its associated factors in a series of Brazilian infants following the final dose of the vaccine at 6 months of age., Methods: Peripheral blood samples were collected after the third dose of the vaccine for the detection of anti-hepatitis B surface antibodies among infants of 7-12 months of age. We measured the association between seroconversion and birthweight, gestational age, time since administration of the vaccine in the maternity hospital and whether or not testing for hepatitis B surface antigen had been performed during pregnancy., Results: We examined 40 infants. The mean birthweight was 2787g (standard deviation=853g) and mean gestational age was 37.5 (standard deviation=3.08) weeks. The proportion that seroconverted was non-significantly higher in infants who weighed ≥2000g at birth (96.7%) than in those with birthweights <2000g (80%, p=0.149). There was no difference between the infants who were born at <37 weeks of gestational age and those born at ≥37 weeks (p<0.178) neither between seroconversion and the time of application of the first dose of the vaccine after delivery (p=0.202)., Conclusion: The proportion of infants who seroconverted was similar to that found in other Brazilian studies. There were no differences in the proportion seroconverting by age at first immunization., (Copyright © 2013 Elsevier Editora Ltda. All rights reserved.)

The protective anti-HBs titres were examined six-year post-immunisation with the Brazilian recombinant hepatitis B vaccine. After the primary vaccination, all adolescents (n = 89) responded with protective anti-HBs titres and had a geometric mean titre (GMT) of 4031.8 mIU/mL. In 2010, 94.5% maintained protective anti-HBs (> 10 mIU/mL) antibodies, with a GMT of 236.0 mIU/mL. A positive correlation was observed between the anti-HBs titres after the primary vaccination and the titres at the six-year follow-up (p < 0.01). Eleven subjects showed anti-HBs titres suggestive of a natural booster. Prostitution and tattoos/piercings were marginally associated with natural boosters in the multivariate analysis. This study showed the first data on anti-HBs persistence following the Brazilian hepatitis B vaccine in sexually active individuals and highlights its effectiveness in the medium term.

Introduction: A decline in hepatitis D virus (HDV) occurrence was described in Europe and Asia. We estimated HDV prevalence in the Brazilian Amazon following hepatitis B vaccination., Methods: This is a cross-sectional survey of HDV measured by total antibodies to HDV (anti-HD T)., Results: HDV prevalence was 41.9% whiting HBsAg carries and was associated with age (PR = 1.96; 95% CI 1.12-3.42; p = 0.01), hepatitis B virus (HBV) infection (PR = 4.38; 95% CI 3.12-6.13; p < 0.001), and clinical hepatitis (PR =1.44; 95% CI 1.03-2.00; p = 0.03). Risk factors were related to HDV biology, clinical or demographic aspects such as underlying HBV infection, clinical hepatitis and age., Conclusions: Our study demonstrated that HDV infection continues to be an important health issue in the Brazilian Amazon and that the implementation of the HBV vaccination in rural Lábrea had little or no impact on the spread of HDV. This shows that HDV has not yet disappeared from HBV hyperendemic areas and reminding that it is far from being a vanishing disease in the Amazon basin.

Objective: To identify factors associated with vaccination against hepatitis B among healthcare workers., Methods: This was a cross-sectional study on 1,808 public-sector healthcare workers in Belo Horizonte, Southeastern Brazil, in 2009. A self-administered questionnaire was used and the vaccination situation was analyzed taking sociodemographic characteristics, lifestyle and working conditions and characteristics into consideration. Univariate (p < 0.20) and multiple (p < 0.05) statistical analyses were performed using Poisson regression to evaluate factors associated with vaccination., Results: Of the workers, 85.6% declared that they had been vaccinated, although only 74.9% of the vaccinated professionals had received a complete immunization schedule. Not having been vaccinated was associated with not having a partner; having high school, technical or incomplete higher education level; work characteristics such as working in surveillance or the administrative/general services sector; and not using personal protection equipment., Conclusions: Groups with lower vaccination coverage were identified. Efforts are required to ensure access and adherence to vaccination among healthcare workers, such as awareness-raising mechanisms.

We conducted a cross-sectional seroprevalence study to determine hepatitis B vaccination coverage and hepatitis B virus (HBV) immunity in a population of young adult males. Specifically, the population is comprised of Air Force conscripts from the metropolitan region of Florianópolis, Santa Catarina, South Brazil, who were born prior to the full implementation of the HBV vaccination program. Of the 371 young males surveyed, 90% received at least 1 dose of the vaccine and 84% completed the 3-dose schedule. Overall, 57% had positive anti-HBs titers. We must continue to vaccinate individuals up to 20 years of age in order to guarantee a significant reduction in cases of hepatitis B virus., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Little is known about the vaccine protective response for infants born from HIV-infected mothers. We evaluated the antibody response to hepatitis B, tetanus, and diphtheria vaccine in vertically HIV-exposed uninfected infants and compared them to those of control infants not exposed to the virus. The quantitative determination of specific neutralizing antibodies against hepatitis B, diphtheria, and tetanus were performed blindly on serum samples. The results showed that 6.7% of the HIV-exposed uninfected individuals were nonresponders to hepatitis B vaccine (anti-HBs titer, <10 mIU/ml), and 64.4% were very good responders (anti-HBs titer, ≥1,000 mIU/ml), whereas only 3.6% of the nonexposed infants were nonresponders (χ(2)=10.93; 1 df). The HIV-exposed uninfected infants showed protective titers for diphtheria and tetanus but lower geometric mean anti-tetanus titers compared to those of the HIV-unexposed infants. Our data point to the necessity of evaluating vaccine immune responses in these children and reinforced that alterations in lymphocyte numbers and functions reported for newborns from HIV-infected mothers interfere with the vaccine response.

Introduction: Hepatitis B infection constitutes an important cause of morbidity and mortality worldwide. In Brazil, however, the current epidemiological situation is not clear. Considering the importance of establishing this prevalence, the aim of this study was to determine the prevalence of HBV markers in voluntary adolescents, junior high (secondary school) students, in the City of Itajaí, State of Santa Catarina, Brazil., Methods: A seroepidemiological, transverse study was conducted with 353 randomly chosen adolescents from elementary school in 2008. Blood samples were analyzed for HBsAg, anti-HBc and anti-HBs. All analyses were conducted by automated microparticle enzyme immunosorbent assay (Abbott®, AxSYM system, Deerfield, IL, USA), according to the manufacturer's instructions., Results: The prevalence of HBsAg was 0.6% (CI 95% 0.1 - 2.0), that of anti-HBc was 1.1% (CI 95% 0.3 - 2.9) and that of detectable anti-HBs was 83.6% (CI 95% 79.3 - 87.3). Hepatitis B vaccination coverage was 97.5% (CI 95% 95.2 - 98.8)., Conclusions: These results demonstrate the success of the vaccination program against hepatitis B in the region studied and indicate that prevention strategies must be maintained and, if possible, expanded to contribute to the establishment of positive prevalence rates in all age groups.

In the present study the frequencies of immunity against hepatitis B (HB) and of potentially contaminating accidents among medical students of a Brazilian public university were evaluated. Of all the 400 students who should have been immunized, 303 (75.7%), 66.3% of whom were women, answered an anonymous, self-administered questionnaire. Serum anti-HBs were determined in 205 of them and titers ≥ 10 UI/L were considered to be protective. A total of 86.8% of students had received three doses of HB vaccine. The frequency of immunity among women (96.4%) was higher (p = 0.04) than that among men (87.7%). Among those who did not have immunity, 12/13 (92.3%) had been vaccinated before entering medical school. Only 11% of the students with complete vaccination had previously verified serological response to the vaccine. A total of 23.6% reported having been somehow exposed to blood or secretions. Among final-year students, this frequency was 45.0%, being similar among men (47.8%) and women (43.2%). Of all these accidents, 57.7% were due to body fluids coming in contact with mucosa and 42.3% due to cut and puncture accidents. The results from this study show that: 1) the frequency of immunity against HB is high among the evaluated medical students, although verification of response to vaccination is not a concern for them; 2) anti-HBs titers should be verified after complete vaccination and on a regular basis, especially by men; and 3) the frequency of potentially contaminating accidents is high.

Background: Hepatitis B infection is the major cause of acute and chronic liver disease, cirrhosis and hepatocellular carcinoma worldwide and has long been recognized as an occupational hazard among dentists. The aim of the present study was to examine factors associated to the self-reporting of hepatitis B vaccination and immunization status among dentists working in the city of Belo Horizonte, Brazil., Methods: A cross-sectional survey was carried out with 1302 dentists in Belo Horizonte, Brazil. After signing a term of informed consent, the participants answered a structured questionnaire on their knowledge regarding their vaccination and immunization status against hepatitis B. Data on demographic, behavioural and occupational exposure aspects were also collected through questionnaires., Results: The results revealed that 73.8% of the dentists reported having received three doses of the vaccine. Multivariate analysis revealed that gender (p = 0.006), use of individual protective equipment (p = 0.021), history of blood transfusion (p = 0.024) and history of illicit drug use (p = 0.013) were independently associated with vaccination against hepatitis B. Only 14.8% had performed a post-vaccination test. The use of individual protective equipment (p = 0.038), dentists who asked patients about hepatitis during dental treatment (p < 0.001), a family history of hepatitis B (p = 0.003) and work experience (p < 0.05) were independently associated with the post-vaccination test., Conclusions: Although there were a large number of vaccinated dentists in Belo Horizonte, the percentage was less than what was expected, as Brazil offers the National Program of Viral Hepatitis Vaccination, which provides free hepatitis B vaccinations to all healthcare workers. Despite being part of a high risk group for contamination, most of the dentists did not know their immunization status.

Objective: To evaluate the immunogenicity and safety of a novel hepatitis B vaccine, after increasing antigen concentration to 25 mug, in comparison to the reference vaccine., Methods: Single-blinded randomized trial comparing VrHB-IB (Instituto Butantan) and the reference vaccine (Engerix B(R), Glaxo Smith Kline). Volunteers aged 31 to 40 years were randomized to either experimental (n=216) or control (n=203) groups, and were given three doses of vaccine. The first dose was administered upon recruitment, and the second and third doses 30 and 180 days later, respectively, between 2004 and 2005. Blood samples were collected for analysis before randomization and after the second and third doses. Active search for adverse effects was perforned in the first five days after vaccination. Differences were evaluated using chi-square and Fisher's exact tests, with a 5% significance level., Results: No severe adverse effects were observed. Seroprotection was confirmed in 98.6% (213/216) of volunteers in the experimental group and 95.6% (194/203) of those in the control group. Geometric mean titers were 12,557 and 11,673, respectively., Conclusions: The Brazilian vaccine was considered to be equivalent to the reference vaccine and its use is recommended for adults.

We evaluated a modified HBV regimen in a cohort of HIV-infected subjects in Rio de Janeiro, Brazil. HIV-infected subjects with no serologic evidences of previous hepatitis B infection were immunized with 4 doses (40 microg each) of recombinant hepatitis B vaccine given at 0, 1, 2 and 6 months. Blood samples were collected 1 month after the last dose and anti-HBs titers were measured. A protective antibody response was defined as an anti-HBs titer >or=10 mIU/mL. Forty-seven subjects (30 women, 17 men; mean age was 36 years, ranging from 21 to 58 years) were included in the final analysis. Median baseline CD4+ lymphocyte count was 402 cells/mm(3) and 33 subjects (70%) had an HIV viral load below 80 copies/mL. A protective antibody response was observed in 42 (89%) subjects. Thirty-seven (78%) and 28 (60%) patients developed anti-HBs titers higher than 100 mIU/mL and 1000 mIU/mL, respectively. 1 out of 5 non-responders (20%) had an HIV viral load below the detection limit, in contrast with 32 (76%) of those with an adequate serologic response (p=0.02). These findings suggest that 4-double dose alternative schedule may be considered to overcome the lower seroconversion rates observed with the standard regimens in HIV-infected subjects., (Copyright (c) 2009 Elsevier Ltd. All rights reserved.)

Objective: The goal was to compare the efficacy of oral 25% dextrose treatment and/or skin-to-skin contact for analgesia in term newborns during intramuscular injection of a hepatitis B vaccine., Methods: A prospective, randomized, partially blinded, clinical trial was performed with 640 healthy term newborns. Infants at 12 to 72 hours of life were assigned randomly to receive an intramuscular injection of hepatitis B vaccine in the right thigh according to 4 analgesia groups, that is, no analgesia (routine); oral 25% dextrose treatment, given 2 minutes before the injection; skin-to-skin contact, initiated 2 minutes before the injection and persisting throughout the procedure; and a combination of the oral dextrose treatment and skin-to-skin contact strategies. For all groups, Neonatal Facial Coding System and Neonatal Infant Pain Scale scores were evaluated before the procedure, during thigh cleansing, during the injection, and 2 minutes after the injection. Premature Infant Pain Profile scores also were assessed for all infants. Pain scores were compared among the 4 groups., Results: The use of oral 25% dextrose treatment reduced the duration of procedural pain in the studied population. Skin-to-skin contact decreased injection pain and duration. The combination of the 2 analgesic measures was more effective than either measure separately for term newborns., Conclusions: Nonpharmacologic analgesic measures were effective for the treatment of procedural pain in term infants. The combination of oral 25% dextrose treatment and skin-to-skin contact acted synergistically to decrease acute pain in healthy neonates.

We conducted a multi-stage household cluster survey to calculate hepatitis B vaccine coverage among children 18-30 months of age in 27 Brazilian cities. Hepatitis B vaccine is administered at birth, 1 month and 6 months of age by Brazil's national immunization program. Among 17,749 children surveyed, 40.2% received a birth dose within one day of birth, 94.8% received at least one dose of hepatitis B vaccine, and 86.7% completed the three-dose series by 12 months of age. Increased coverage with the birth dose and administration of hepatitis B in combination with diphtheria-tetanus-pertussis-Haemophilus influenzae type b antigens could improve protection against hepatitis B.

Infant exposure to ethylmercury (EtHg) has not only increased but is starting earlier as a result of the current immunization schedule that uses thimerosal-containing vaccines (TCVs). Although vaccination schedule varies considerably between countries, infants in less-developed countries continue to be exposed to EtHg derived from more affordable TCVs. We studied the exposure of newborns to EtHg from hepatitis B vaccines; hospital records (21,685) were summarized for the years 2001 to 2005 regarding date of birth, vaccination date, and birth weight. Most of the vaccinations occurred in the first 24 hours postdelivery; over the 5 years, there was an increase in vaccinations within hours of birth (same day), from 7.4% (2001) to 87.8% (2005). Nearly 94.6% of infants are now being vaccinated within the first 24 hours. Range of mercury exposure spread from 4.2 to 21.1 microg mercury/kg body weight for those receiving TCVs with the highest thimerosal concentration; these exposure levels are conservative for 2% of children receiving vaccines within 2 to 3 postnatal days, when they are still going through physiological postnatal weight loss. Because of the particular timing (transitioning from in utero to ex utero metabolism) and specific aspects of exposure (i.e., parenteral mode, bypassing gastroenteric barriers) and dose (related to vaccine manufacturer and with variation in birth weight), this study reveals critical issues that can modulate toxicokinetics and toxicodynamics of organomercurials in neonates.

The aim of this study was to determine the frequencies of serological markers for hepatitis B and risk factors associated with HBV infection among young women living in Vitória, Espírito Santo, where vaccination for newborns and adolescents started in 1994 and 2000, respectively. This was a population-based study performed by sampling in three health regions of Vitória in 2006. Interviews were held and HBsAg, anti-HBc and anti-HBs were investigated. Out of 1,200 women selected, 1,029 (85.7%) were enrolled. The median age was 23 years (interquartile range: 20-26 years) and 93.2% had had more than four years of schooling. Forty-three women (4.2%; 95%CI 2.97%-5.43%) were positive for anti-HBc total, and nine, for HBsAg (0.9%; 95%CI 0.4%-1.6%)]. There were 466 positive anti-HBs tests (45.3%; 95%CI 42.2%-48.4%), of which 427 were negative for anti-HBc and HBsAg. Monthly income of up to four minimum monthly salaries was the only variable independently associated with positive anti-HBc tests (OR = 2.6: 95%CI 1.06-6.29). These data show low prevalence of the hepatitis B virus and its better-known risk factors. The prevalence of positive anti-HBs tests with negative anti-HBc and HBsAg tests reflects the vaccine coverage in the municipality in this group (43.7%). It was not possible to determine any significant risk factors for hepatitis B virus acquisition among this population.

Background: Although various studies have demonstrated efficacy of DNA-recombinant anti-hepatitis B vaccines, their effectiveness in health care settings has not been researched adequately. This gap is particularly visible for blood donors, a group of significant importance in the reduction of transfusion-transmitted hepatitis B., Methods: This is a double cohort study of 1411 repeat blood donors during the period 1998-2002, involving a vaccinated and an unvaccinated cohort, with matching of the two in terms of sex, age and residence. Average follow-up was 3.17 person-years. The outcome measure was infection with hepatitis B virus (HBV), defined by testing positive on serologic markers HBsAg or anti-HBC. All blood donors were from the blood bank in Joaçaba, federal state of Santa Catarina, Brazil., Results: The cohorts did not differ significantly regarding sex, age and marital status but the vaccinated cohort had higher mean number of blood donations and higher proportion of those residing in the county capital Joaçaba. Hepatitis B incidences per 1000 person-years were zero among vaccinated and 2,33 among non-vaccinated, resulting in 100% vaccine effectiveness with 95% confidence interval from 30,1% to 100%. The number of vaccinated persons necessary to avoid one HBV infection in blood donors was estimated at 429 with 95% confidence interval from 217 to 21422., Conclusion: The results showed very high effectiveness of DNA-recombinant anti-HBV vaccines in blood donors. Its considerable variation in this study is likely due to the limited follow-up and the influence of confounding factors normally balanced out in efficacy clinical trials.

Aim: Brazilian newborns immunized with hepatitis-B (thimerosal containing vaccine, TCV) receive the first dose within 24 h if delivered in public hospitals, but at a later time if born in private hospitals. We compared neurodevelopment (ND) in infants born in a state hospital (immunized within 24 h) and in privately run hospitals (immunized 2-4 days postnatally)., Methods: We used the Gesell Developmental Schedules in 82 healthy exclusively breastfed infants at 6 months to assess motor skills, language development, comprehension capacity and social skills., Results: Compared to the group immunized 2-4 days after hospital discharge, the group immunized within 24 h showed no significant difference in ND delays. Despite the variation in gestational age (range 36-42 weeks) and TCV-ethylmercury (EtHg) dose (5.7-11.3 microg Hg/kg b.w.) at birth, time of exposure to TCV showed no significant association with ND. Gesell Developmental Score was not significantly correlated with total parenteral EtHg/unit of body mass neither with the relative increase in hair-Hg (as an additional challenge to prenatal Hg exposure)., Conclusion: In breastfed infants, differences in early exposure to TCV-EtHg cannot portend clinical neurodevelopment delays at 6 months. We speculate that breastfeeding remains a significant strategy to improve central nervous system protection of infants facing early exposure challenges.

Objective: The aim of this study was to verify the practices and attitudes of senior dental students about infection control procedures., Methods: A cross-sectional survey was performed during the 1st semester of 2003. Open- and close-ended questions were given to 196 students in 6 universities., Results: Overall, 90.8% of students had been vaccinated for hepatitis B. Only 25.0% have been assessed for anti-HBs. A total of 99.5% students reported always using gloves for all procedures. Eye protection were always used by 84.2% of students, and all the students used face masks for all procedures. Caps or hair covers were used by 92.3% of students and 87.8% reported no objection to treating patients with infectious diseases. Among instructors, the students observed that 60.2% of them did not use gloves for all procedures, 43.4% of those didn't change gloves between patients., Conclusions: These results address the need for an improved quality assurance, in order for the students and faculty to improve their practices and attitudes on infection control measures.

The objective of this work was to estimate the effectiveness of DNA recombinant anti-HBV vaccines in a retrospective cohort study of 1,012 Brazilian blood donors who completed the vaccination schedule (3 doses + booster of antibody titer < 10IU/L) during the period 1998-2002. The results showed that seroconversion rates were significantly lower among the donors whose antibody titers was measured six months after completing the vaccination scheme and among older donors, particularly those aged over 50. Overall vaccine effectiveness was 88.7%, ranging from 80.6% in the oldest (50 years or over) to 91.4% among the youngest (18-30 years) donors. The booster regimen was effective at reducing the percentage of non-responders. We conclude that vaccine effectiveness was significantly better in younger blood donors and that the anti-HBs testing interval influenced the vaccine effectiveness.

The prevention of hepatitis B by vaccination is one of the most efficient tools to avoid the transmission of the virus. This study evaluated the immunogenicity of the national vaccine Butang in children born in Campo Mourão City, state of Paraná, Brazil, aged 7 to 12 months, by determining the anti-HBsAg antibodies levels after completion of the National Immunization Program Protocol for hepatitis B. All 70 children evaluated by the MEIA method (immune-enzymatic micro particles) showed seroconversion to the Butang vaccine. Nine children (12.9%) presented a low response, with anti-HBs titers between 11 and 100 mUI/ml; 39 children (55.7%) showed a good response to the vaccine, with titers between 101 and 1000 mUI/ml; and 22 children (31.4%) showed antibodies titers higher than 1000 mUI/ml. The mean titer of the anti-HBs antibody titers was 1408.1 +/- 2870.26 mUI/ml (15.7 to 19560.0 m UI/ml). The levels of antibodies produced by the prematurely-born children were not statistically different from those found in the newborns. Fifty-five children were also evaluated through the ELFA method (ELISA with a final detection in fluorescence), which presented similar results. The results obtained in our study corroborated the effectiveness of the national vaccine Butang in newborn children of Campo Mourão City, Paraná, even if they were premature.

This study investigated the seropositivity for hepatitis B virus (HBV), the vaccination index, and the vaccine response index in dentists from Campo Grande, MS. Blood samples from 474 dentists (63.7% women and 36.3% men), with a mean age of 38.5 +/- 10.5 years were analyzed by enzyme-linked immunosorbent assay to detect the serological markers: HBsAg, anti-HBs, and anti-HBc. The HBsAg positive samples were tested for anti-HBc IgM, HBeAg, and anti-HBe. A total of 51 (10.8%) dentists showed seropositivity for HBV. Three (0.6%) were HBsAg/anti-HBc/anti-HBe positive, 43 (9.1%) were anti-HBc/anti-HBs positive, and 5 (1.1%) had only anti-HBc. Viral DNA was detected by polymerase chain reaction in 9 (17.6%) out of 51 HBV seropositive samples. A vaccination index of 96.6% (458/474) was observed, although 73.1% (335/458)completed the three-dose schedule. Excluding 46 HBV seropositive individuals from 458 that reported vaccination, 412 were analyzed for vaccine response index. It was observed that 74.5% (307/412) were anti-HBs positive; this percentage increased to 79.1% when three doses were administered. The results showed a high vaccination index and a good rate of vaccine response; however, the failure in completing the three-dose schedule and the occurrence of HBV infection reinforce the need for more effective prevention strategies.

Objective: To evaluate the immunogenicity of a combined DTPa-HB vaccine co-administered with Haemophilus influenzae type b conjugate vaccine (PRP-T) in Brazilian infants., Material and Methods: A prospective and open clinical study, in which 110 infants were immunized with a three-dose primary vaccination regime at two, four and six months of age and with a single booster vaccination. Blood samples were drawn immediately before the first dose, one month after the third dose, at the time of the booster dose and one month after the booster to assess seropositivity and antibody geometric mean titers (GMTs) of antibodies for diphtheria, tetanus, hepatitis B, Haemophilus influenzae type b and for the three pertussis antigens: Pertussis Toxin (PT), Filamentous Hemagglutinin (FHA) and Pertactin (PRN)., Results: Among the original 110 infants, 93 completed the study. Seropositivity was 100% for all seven involved antibodies, after the primary vaccination course. At the time of the booster dose, all antibodies (except diphtheria 33.7% and anti-PT 59%) were seropositive for more than 94% of subjects. After the booster, seropositivity increased to 100% for all antibodies. The GMT of these antibodies followed a similar pattern, with a strong increase after the primary course, followed by a second increase after the booster dose. At this time, GMT was 2- to 7-fold higher than after the primary course, for all vaccine components., Conclusions: Concomitant administration of DTPa-HB and Hib vaccines elicited strong seroprotection for all the antigenic components. No interference with antibody response was evident. The vaccines provided high immunogenicity, following both the primary vaccinations and the booster dose.

In 1999, on the occasion of the application of the first vaccine dose during the state vaccination campaign against hepatitis B virus (HBV), 390 individuals from the town of Rio Branco, Acre, aged two or more years were selected for the determination of the seroprevalence of HBV and HCV. HBV markers (HBsAg, anti-HBs, and anti-HBc IgG) were determined on this occasion and anti-HBs antibodies were also assessed 30 days after the third vaccine dose. At the time of vaccination, 39% of the individuals were still susceptible to HBV, while 61% presented serologic evidence of previous HBV contact or previous vaccination. The individuals with previous HBV contact were significantly older (p<0.001) than those without HBV markers. Of the 192 individuals who returned for reexamination, 30 days after the third dose, 158 (82.3%) had received three vaccine doses, and only 60 (31.2%) belonged to the group without HBV markers. In these individuals, the seroconversion rate after the third dose was 92% (55/60). In conclusion, we found considerable HBV in this population, indicating the need for pursuing the immunization programs. We also found high rates of vaccination coverage in the Western Brazilian Amazon region.

Objective: Serological studies in several countries have found a higher prevalence of hepatitis B virus (HBV) among dentists when compared to the general population, especially among surgical specialties. The present study was carried out to determine the prevalence of hepatitis B (HB) vaccination and factors associated with no vaccination and incomplete vaccination among dentists., Methods: A survey was conducted among 299 dentists living in Montes Claros, southeast Brazil, using a self-administered questionnaire. HBV vaccination prevalence was determined according to the number of doses of vaccine and factors associated with no vaccination or incomplete HBV vaccination were investigated using multinomial logistic regression analysis., Results: Participation rate in the study was very high (296/299). Of the participants, 74.9% received three doses of HBV vaccine, 14% two doses, 2% a single dosis and 10% were not vaccinated. Complete vaccination rate was higher among surgeons and periodontists (89%). The main reason reported for not being vaccinated or incomplete vaccination was the need of more information. No vaccination was significantly higher among dentists aged 40 years and over (OR=8.62; 95%CI: 1.88-39.41) and those who did not attend refreshment courses in the last two years prior to the survey (OR=2.72; 95%CI: 1.02-7.22). Incomplete vaccination was positively associated with non-use of gloves during work (OR=2.32; 95%CI: 1.08-4.97)., Conclusions: Lack of information, possibly associated to lower attendance to refreshment courses, seems to be one of the main factors affecting the vaccination rate.

Objective: To carry out a survey of hepatitis B virus seroepidemiology in a municipality in central Brazil, on the border of two large ecosystems, the cerrado (savanna) and the Amazon River basin., Methods: The municipality studied, Nova Mutum, is located in the north central portion of the Brazilian state of Mato Grosso. The study sample of 754 individuals included persons from families, selected at random, who were living in the municipality's urban center as well as all the individuals living in a nearby rural village. Ages ranged from 2 to 79 years. All eligible individuals were interviewed. Blood was collected and used to assess hepatitis B virus markers by enzyme-linked immunosorbent assay., Results: Hepatitis B virus infection was found in 232 individuals, or 31% of them; 19 of them (3%) were HBsAg-positive. Of the 754 persons, 149 of them (20%) who reported having been vaccinated against hepatitis B and who presented anti-HBs positivity were classified as vaccine responders. With the multivariate analysis, the variables found to be associated with exposure to hepatitis B virus were having begun sexual relations, having been vaccinated against yellow fever with a needle-free jet injection gun (for the age group < 20 years), and being an immigrant from southern Brazil (> 20 years). Vaccine coverage was low among individuals older than 10 years. The largest share of susceptible individuals (74%) were found in the age group of 11 to 20 years., Conclusions: Our data suggest that hepatitis B virus vaccine coverage in Brazil should be extended to include teenagers in populations that have a low to moderate hepatitis B virus prevalence. It is likely that our results can be extrapolated to other areas of Latin America with a similar epidemiological pattern.

Hepatitis B vaccine is the most effective strategy for preventing the transmission of hepatitis B virus (HBV) in haemodialysis centers. Nevertheless, lower vaccine responses have been reported in haemodialysis patients as compared with healthy subjects. This study examines the response to Euvax-B in Brazilian haemodialysis patients and staff. A total of 102 eligible patients (n = 42) and staff members (n = 60) consented to be studied. Patients were immunized intramuscularly with four doses of 40 microg of Euvax-B vaccine at 0, 1, 2 and 6 months. In staff members, the vaccine was administered in three doses of 20 microg at 0, 1, and 6 months. Post-vaccine samples were taken from all subjects I month after each dose. The vaccine response was determined by measuring antibody to the hepatitis B surface antigen (anti-HBs) levels using ELISA. Subjects with anti-HBs titres equal to or higher than 10 UI/L were considered immune protected. Of the haemodialysis patients who received four doses of hepatitis B vaccine, 89.5% responded to Euvax-B vaccine. The geometric mean of anti-HBs titres was 322.8 IU/L (95% CI: 317.7-328). Among staff members, 93.3% reached anti-HBs protective titres after the third vaccine dose. The geometric mean of anti-HBs titres was 2,209 IU/L (Cl: 2,198-2,219). Age, male gender and body mass index were not associated with vaccine response in either group. This study showed a good immunogenicity response to Euvax-B in haemodialysis patients and staff.