Characterization of hepatitis B virus in Amerindian children and mothers from Amazonas State, Colombia

Global prevalence of occult HBV infection in children and adolescents: A systematic review and meta-analysis

INTRODUCTION AND OBJECTIVES

Occult HBV infection (OBI) is a specific form of hepatitis B virus (HBV) infection and has the possibility of developing into hepatocellular carcinoma (HCC) in adults. This study aimed to estimate the global prevalence of occult HBV infection in children and adolescents.

MATERIALS AND METHODS

We systematically searched PubMed, Embase, Web of Science, and Cochrane databases for relevant studies on the prevalence of OBI in children and adolescents. Meta-analysis was performed using STATA 16 software.

RESULTS

Fifty studies were included. The overall prevalence of OBI in children and adolescents was 7.5% (95% CI: 0.050-0.103). In different risk populations, OBI prevalence was remarkably high in the HIV-infected population (24.2%, 95% CI: 0.000-0.788). The OBI prevalence was 0.8% (95% CI:0.000-0.029) in the healthy population, 3.8% (95% CI:0.012-0.074) in the general population, and 6.4% (95% CI: 0.021-0.124) in children born to HBsAg-positive mothers. Based on different serological profiles, the prevalence of OBI in HBsAg-negative and anti-HBc-positive patients was 6.6% (95% CI: 0.016-0.136), 3.0% (95% CI: 0.009-0.059) in HBsAg-negative and anti-HBc-negative patients, 4.6% (95% CI: 0.015-0.088) in HBsAg-negative and anti-HBs-positive patients, and 3.7% (95% CI: 0.001-0.102) in HBsAg-negative and anti-HBs-negative patients.

CONCLUSIONS

Despite HBV vaccination and hepatitis B immunoglobulin (HBIG), OBI is common in children and adolescents in high-risk groups.

Host and HBV Interactions and Their Potential Impact on Clinical Outcomes

Hepatitis B virus (HBV) is a challenge for global health services, affecting millions and leading thousands to end-stage liver disease each year. This comprehensive review explores the interactions between HBV and the host, examining their impact on clinical outcomes. HBV infection encompasses a spectrum of severity, ranging from acute hepatitis B to chronic hepatitis B, which can potentially progress to cirrhosis and hepatocellular carcinoma (HCC). Occult hepatitis B infection (OBI), characterized by low HBV DNA levels in hepatitis B surface antigen-negative individuals, can reactivate and cause acute hepatitis B. HBV genotyping has revealed unique geographical patterns and relationships with clinical outcomes. Moreover, single nucleotide polymorphisms (SNPs) within the human host genome have been linked to several clinical outcomes, including cirrhosis, HCC, OBI, hepatitis B reactivation, and spontaneous clearance. The immune response plays a key role in controlling HBV infection by eliminating infected cells and neutralizing HBV in the bloodstream. Furthermore, HBV can modulate host metabolic pathways involved in glucose and lipid metabolism and bile acid absorption, influencing disease progression. HBV clinical outcomes correlate with three levels of viral adaptation. In conclusion, the clinical outcomes of HBV infection could result from complex immune and metabolic interactions between the host and HBV. These outcomes can vary among populations and are influenced by HBV genotypes, host genetics, environmental factors, and lifestyle. Understanding the degrees of HBV adaptation is essential for developing region-specific control and prevention measures.

Epidemiology and Genetic Diversity of Hepatitis B Virus and Hepatitis Delta Virus Infection in Indigenous Communities in Colombia

Despite the universal vaccination program, there are still regions and territories with a high prevalence of Hepatitis B Virus infection (HBV), such as the Amazon basin, where several indigenous communities live. Additionally, Hepatitis Delta Virus (HDV) is a defective that requires the hepatitis B surface antigen (HBsAg) for the assembly and release of de novo viral particles. Therefore, hepatitis D could be the result of HBV/HDV coinfection or HDV superinfection in individuals with chronic hepatitis B. Among the high prevalence HDV populations are indigenous communities of America. This study aims to describe and characterize the frequency of HBV and HDV infection, viral genotypes and HBV immune escape mutants in indigenous populations from different regions of Colombia. The diagnosis of hepatitis B and hepatitis D was confirmed by serological markers. Moreover, the HBV and HDV genome were amplified by PCR and RT-PCR, respectively, and, subsequently, the phylogenetic analysis was performed. We characterized 47 cases of chronic hepatitis B, 1 case of reactivation and 2 cases of occult hepatitis B infection (OBI). Furthermore, a high prevalence of HDV infection was identified in the study population (29.33%, 22/75) and the circulation of several HBV genotypes and subgenotypes (F1b, F3, F4, and D). Interestingly, this is the first report of the HDV genotype I circulation in this country. These findings demonstrated that HBV and HDV infections are still public health problems in indigenous communities in Colombia.

Vertical Transmission of Hepatitis B Virus-An Update

Hepatitis B virus (HBV) infection is a major public health problem in the world. Approximately 296 million people are chronically infected. In endemic areas, vertical transmission is a common route of transmission. There are several strategies for the prevention of HBV vertical transmission, such as antiviral treatment during the third trimester of pregnancy and immunoprophylaxis to newborns that includes the administration of hepatitis B immune globulin (HBIG) and an HBV vaccine. Despite this, immunoprophylaxis failure can occur in up to 30% of infants born to HBeAg-positive mothers and/or with high viral load. Therefore, management and prevention of HBV vertical transmission is of paramount significance. In this article, we provided a review of the epidemiology, mechanisms of pathogenesis and risk factors of vertical transmission, as well as the strategies implemented to prevent the infection.

[Hepatitis B in indigenous people in Latin America: a literature reviewHepatite B em indígenas na América Latina: revisão da literatura]

Objetivo.

Identificar publicaciones realizadas entre los años 2000 y 2020 sobre hepatitis B en indígenas de América Latina, con el fin de conocer avances y vacíos en el tema durante los últimos 20 años.

Métodos.

Revisión exploratoria y síntesis rápida de la evidencia. El proceso de organización documental se realizó con los programas Excel^® y Rayyan^®.

Resultados.

Se seleccionaron 30 de 107 artículos encontrados, 17 corresponden a estudios epidemiológicos, 10 a revisiones documentales, dos estudios clínicos y una carta al editor. Brasil fue el país con más publicaciones (50%), la mayoría con enfoque epidemiológico. La temática más abordada fue la medición de prevalencia de la infección por hepatitis B con 22 publicaciones, le siguieron 11 estudios que informan resultados de estudios moleculares del virus, siete estudios sobre vacunación, cinco estudios sobre factores de riesgo y cuatro publicaciones con temas como la transmisión vertical y estudios sociales.

Conclusión.

En comparación con revisiones previas realizadas por otros autores, se observa una mayor diversidad en los temas y métodos de investigación utilizados; sin embargo, aún prevalecen los enfoques epidemiológicos convencionales centrados en la medición de la prevalencia de marcadores serológicos. Esto hace necesario encarar otro tipo de investigaciones centradas en los determinantes socioculturales.

[Epidemiology of hepatitis C virus infection in ColombiaEpidemiologia da infecção pelo vírus da hepatite C na Colômbia]

OBJECTIVE

To describe the epidemiology of hepatitis C virus (HCV) infection in Colombia.

METHODS

Critical review of epidemiological studies of HCV infection in Colombia. The PubMed, SciELO, and ScienceDirect databases were searched for original articles and reviews on the subject published from 1989 to 2020. Reports from the National Institute of Health and the High Cost Account of the Ministry of Health and Social Protection were also reviewed.

RESULTS

Data on seroprevalence of HCV antibodies in blood donors range from 1.5% to 0.32%, corresponding to reports at the beginning and end of the study period, respectively. In the population with risk factors, a high prevalence of HCV infection is observed, although with variations over time. With respect to HCV genotypes in Colombia, genotypes 1, 2, 3, and 4 (subtypes 1a, 1b, 2a, and 3a) have been identified.

CONCLUSIONS

In the observation period, a decrease was seen in seroprevalence of HCV infection in blood donors and hemodialysis patients in Colombia, demonstrating the impact of safe blood policies and biosafety measures. Studies in people who inject illicit drugs indicate a high prevalence of infection, with regional differences within the country. HCV genotype 1, subtype 1b, is the most frequent in the different studies carried out in Colombia, and the most recent report of the High Cost Account of the Ministry of Health and Social Protection indicates that genotype 4 is the second most frequent genotype in the country.

Prevalence of hepatitis B/C viruses and associated factors in key groups attending a health services institution in Colombia, 2019

Both hepatitis B virus (HBV) and hepatitis C virus (HCV) are major sources of morbidity and mortality worldwide; however, their prevalence in key groups in Colombia is not yet known. We aimed to analyse the prevalence of HBV and HCV and its associated factors in key groups who were treated at an institution providing health services in Colombia during 2019. This was a multiple-group ecological study that included 2,624 subjects from the general population, 1,100 men who have had sex with men (MSM), 1,061 homeless individuals, 380 sex workers, 260 vulnerable young people, 202 drug users, 41 inmates and 103 people from the lesbian, gay, bisexual and transgender community. Prevalence of infection with a 95% confidence interval and its associated factors was calculated for each group. Confounding variables were assessed using logistical regression and SPSS 25.0 software. Prevalence of HBV and HCV in the general population was 0.15% and 0.27%, respectively; 0.27% and 2.09% in MSM; 0.37% and 2.17% amongst homeless individuals; 0.26% and 0.0% amongst sex workers; 0.39% and 0.0% amongst vulnerable youth; and 5.94% and 45.54 amongst injecting drug users. In the multivariate HBV model, the explanatory variables included the study group, city of origin and the type of health affiliation; for HCV they were group, origin, sex, age group, health affiliation, use of drugs and hallucinogen use during sexual intercourse. A high prevalence of HBV and HCV were evidenced for both viral infections, which was, consequently, much higher within the key groups. The main associated factors that were identified related to origin and type of health affiliation and demonstrated a double vulnerability, that is, belonging to groups that are discriminated and excluded from many health policies and living under unfavourable socioeconomic conditions that prevent proper affiliation and health care.

MARCADORES SEROLOGICOS DEL VIRUS DE HEPATITIS B EN PUEBLOS INDIGENAS DEL ESTADO AMAZONAS, VENEZUELA

Venezuela presenta un nivel de prevalencia intermedia de Hepatitis B, con cuatro focos de alta endemicidad asociados principalmente a población indígena. Las prevalencias halladas en el Amazonas venezolano tienen distintas distribuciones entre los pueblos, observándose diferentes particularidades epidemiológicas. El objetivo del presente trabajo fue reportar la prevalencia de VHB en población indígena de diferentes pueblos y regiones geográficas del estado Amazonas, que no habían sido evaluados hasta la fecha, mediante la determinación de los marcadores serológicos: Antígeno de Superficie del Virus de Hepatitis B (AgsHB) y Anticuerpos Anticore (Anti-HBc). Se estudiaron 1390 individuos de 15 pueblos indígenas (Baniva, Baré, Curripaco, Jivi, Mapoyo, Maco, Piapoco, Piaroa, Puinave, Sáliba, Warekena, Yabarana, Yanomami, Yekuana, Yeral), resultando una prevalencia de exposición al Virus de 37,6 % (Anti-HBc), y una prevalencia de infección activa de 5,6 % (AgsHB). La prevalencia de exposición al virus es proporcional a la edad. No se encontró diferencia significativa en relación al sexo. La exposición al virus en el pueblo Sáliba fue significativamente menor al resto de los pueblos indígenas (p<0,001), y la observada en Yabarana, significativamente mayor (p<0,001). Se encontró una prevalencia de AgsHB significativamente mayor (p<0,01) en el pueblo indígena Yabarana. Se puede predecir que existe relación entre prevalencia de exposición al virus de hepatitis B y la distancia geográfica al centro urbano.

Approach to women who become pregnant while on tenofovir disoproxil fumarate for chronic B hepatitis: A report of two cases

Mother-to-child transmission of hepatitis B virus can occur during the intrauterine, antenatal and postnatal periods, with an increased risk of perinatal transmission. Appropriate management of patients who are hepatitis B surface antigen positive during pregnancy can substantially reduce the rates of perinatal transmission. Herein, two pregnant women with chronic hepatitis B are presented; one became pregnant while receiving tenofovir disoproxil fumarate and continued the treatment during pregnancy, the other discontinued tenofovir disoproxil fumarate treatment on her own due to conception, but restarted at 26 weeks of pregnancy. At birth the newborns of both women were vaccinated and immunoglobulin was given, with no perinatal transmission. Whether pregnant women should receive antiviral therapy or immunoprophylaxis still remains controversial. In order to keep the mother's liver stable and to prevent perinatal transmission, it is of paramount importance to manage pregnant women in line with the current information and guidelines.

Prevalence of viral sexually transmitted infections and HPV high-risk genotypes in women in rural communities in the Department of La Paz, Bolivia

Background

Bolivia has the highest prevalence of cervical cancer in South America and the prevalence of viral sexually transmitted infections (STIs) among people in urban cities is increasing. Little is known about the prevalence of viral STIs in rural communities, which generally have limited access to health care. In order to study the prevalence of viral STIs in rural Bolivia, we recruited women from villages and towns in the Department of La Paz in Bolivia.

Methods

Three hundred ninety-four female participants were assessed for IgG-antibodies to herpes simplex virus type 2 (HSV-2), human immunodeficiency virus (HIV) and hepatitis B virus (HBV, anti-HBc), as well as for the presence of HBV surface antigen (HBsAg) in dried blood spots. The prevalence of 12 high-risk types of human papillomavirus (HPV) was assessed by qPCR in dried cervicovaginal cell spots from 376 of these women. χ² test was used to compare variables between the populations and binary logistic regression was used to identify risk factors associated with the positivity of the tests.

Results

The seroprevalence of HSV-2 was 53% and of HBV 10.3%. HBAg was detected in 15.8% of women with anti-HBV antibodies indicating chronic infection. The frequency of high-risk HPV infection was 27%, with the most prevalent high-risk HPV types being HPV 56, 39 and 31 followed by HPV 16 and 18. Finally, none of the 394 women were seropositive for HIV, and about 64% of the studied population was positive for at least one of the viral infections.

Conclusions

Women in Bolivian rural communities in La Paz show a high prevalence of HBV, HPV and, in particular, HSV-2. In contrast, none of the women were HIV positive, suggesting that the HIV prevalence in this population is low. The pattern of high-risk HPV types differed from many other countries with a predominance of HPV-types not included in the Gardasil vaccine which was officially introduced in Bolivia in April 2017.