Perfil epidemiológico e genotípico da infecção pelo vírus da hepatite B no Norte de Portugal

Hepatitis B Virus Genotypes and Subgenotypes Circulating in Infected Residents in a Country with High Vaccination Rate

Despite the availability of a vaccine against hepatitis B virus (HBV), this infection still causes public health problems, particularly in susceptible populations. In Portugal, universal free vaccination started in 1994, and most HBV infections are diagnosed in immigrants from high-prevalence countries. Our aim was to assess the pattern of HBV genotypes/subgenotypes in samples collected between 2017 and 2021 from a convenience sample of 70 infected residents in Portugal. The HBV pol/HBsAg region was amplified and sequenced, allowing the analysis of RT sequences submitted to phylogenetic analysis and mutations assessment. A total of 37.1% of samples were from native Portuguese, aged 25-53 years (mean: 36.7 years), and the remaining samples were from individuals born outside of Portugal. A high diversity of HBV was identified: subgenotypes A1-A3 in 41.0% (16/39); D1, D3, and D4 in 30.7% (12/39); E in 23.1% (9/39); and F4 in 2.6% (1/39). Besides genotypes A and D, Portuguese were also infected with genotypes E and F, which are prevalent in Africa and South America, respectively. Resistance mutations in RT sequences were not found. The findings provide valuable insights for updating the HBV molecular epidemiology in Portugal. However, successful strategies to prevent and control the infection are still needed in the country, especially among susceptible and vulnerable populations.

Phylogeography of hepatitis B virus: The role of Portugal in the early dissemination of HBV worldwide

In Portugal, the genetic diversity, origin of HBV and the Portuguese role in the dissemination of HBV worldwide were never investigated. In this work, we studied the epidemic history and transmission dynamics of HBV genotypes that are endemic in Portugal. HBV pol gene was sequenced from 130 patients followed in Lisbon. HBV genotype A was the most prevalent (n = 54, 41.5%), followed by D (n = 44, 33.8%), and E (n = 32, 24.6%). Spatio-temporal evolutionary dynamics was reconstructed in BEAST using a Bayesian Markov Chain Monte Carlo method, with a GTR nucleotide substitution model, an uncorrelated lognormal relaxed molecular clock model, a Bayesian skyline plot, and a continuous diffusion model. HBV subgenotype D4 was the first to be introduced in Portugal around 1857 (HPD 95% 1699-1931) followed by D3 and A2 a few decades later. HBV genotype E and subgenotype A1 were introduced in Portugal later, almost simultaneously. Our results indicate a very important role of Portugal in the exportation of subgenotypes D4 and A2 to Brazil and Cape Verde, respectively, in the beginning of the XX century. This work clarifies the epidemiological history of HBV in Portugal and provides new insights in the early and global epidemic history of this virus.

Epidemiology of hepatitis B in Portugal

The epidemiology of hepatitis B in Portugal is insufficiently characterized. We aimed to review the epidemiology of hepatitis B in Portugal since 1980. A literature review was performed in MEDLINE, Scielo, Web of Science, and the Portuguese Scientific Repository for studies containing 'Hepatitis B' and 'Portugal' published from 1980 to June 2016. The initial search was complemented by abstract books from national gastroenterology and hepatology meetings and reports from the Service for Intervention on Addictive Behaviours and Dependences, the Portuguese Blood Institute, and Directorate-General of Health. Further studies were identified in references of retrieved papers and https://www.google.pt. Ninety references were included. Hepatitis B surface antigen (HBsAg) prevalence was up to 2% in the general population and decreased in the last decades: 1.13-2.0% in studies carried out in 1980-1989 and 0.02-1.45% in studies carried out in 1990-2014. Among pregnant women, HBsAg prevalence was 1.35% in those on primary care, but 6.2% among risk parturients. Among drug abusers, HBsAg prevalence decreased from 10-19.6% in the decades of 1980-1990 to 4.8% in 2014. Higher HBsAg prevalence rates were observed among populations of African or Asian origin. Individuals with hepatitis B were mostly men, mean age 36.9-49 years. The most frequent viral genotype was D. Genotype E is more prevalent in patient cohorts from Central-Southern Portugal (10-62%) than those from Northern Portugal (1-4.1%). The proportion of inactive carriers varied from 24.2 to 73%. The prevalence of cirrhosis varied from 5.8 to 23.7%. Portugal is a low-endemicity country for hepatitis B. Nevertheless, prevalence is high among specific subgroups that may benefit from specifically designed healthcare programs.

Vacinação contra hepatite B e exposição ocupacional no setor saúde em Belo Horizonte, Minas Gerais

OBJETIVO: Identificar fatores associados à vacinação contra hepatite B em trabalhadores da saúde. MÉTODOS: Estudo transversal com 1.808 trabalhadores da saúde do setor público de Belo Horizonte, MG, em 2009. Questionário autoadministrado foi usado e a situação vacinal foi analisada considerando características sociodemográficas, estilo de vida, características e condições de trabalho. Análises estatísticas univariada (p < 0,20) e múltipla foram realizadas utilizando regressão de Poisson (p < 0,05) para avaliação de fatores associados à vacinação. RESULTADOS: Declararam ter sido vacinados 85,6% dos trabalhadores, 74,9% dos quais receberam esquema completo da vacina. Não ter sido vacinado associou-se a não ter companheiro, a escolaridade em nível médio/técnico ou superior incompleto e a características do trabalho, como atuar na vigilância ou setor administrativo/serviços gerais e não utilizar equipamentos de proteção individual. CONCLUSÕES: Foram identificados grupos com menor cobertura vacinal. São necessários esforços para garantir o acesso e a adesão à vacinação a todos os grupos ocupacionais.