Hepatitis B virus DNA in saliva from children with chronic hepatitis B infection: implications for saliva as a potential mode of horizontal transmission

Quantification of domestic cat hepadnavirus DNA in various body fluid specimens of cats: the potential viral shedding routes

Domestic cat hepadnavirus (DCH) belongs to the Hepadnaviridae family together with human hepatitis B virus (HBV) that remains to be a major health problem worldwide. The transmission of HBV infectious virion has been one of the essential factors that contribute to high number of HBV infection in humans. It has been long known that various body fluid specimens of human with chronic HBV infection contain HBV DNA and demonstrated to be infectious. In contrast to this knowledge, the detection of DCH in various body fluid specimens of cats, has not been reported. This study explored the detection of DCH DNA in various body fluid specimens of cats by quantitative polymerase chain reaction (qPCR) and investigated whether the detection of DCH DNA from broader routes was correlated with any genomic diversity by phylogenetic analysis. A total of 1,209 body fluid specimens were included, and DCH DNA was detected not only in 4.70% (25/532) of blood samples; but also in 12.5% (1/8), 1.14% (1/88), 2.54% (10/394), and 1.65% (3/182) of auricular swab (AS), nasal swab (NS), oral swab (OS), and rectal swab (RS) specimens, respectively. Furthermore, the level of DCH DNA detected in the blood was significantly correlated with DCH DNA detection in OS (P = 0.02) and RS (P = 0.04) specimens. Genomic analysis revealed that there was no notable genomic diversity within the complete genome sequences obtained in this study. In conclusion, this study highlighted the presence of DCH DNA in various body fluid specimens of cats, and the potential role of these specimens in DCH horizontal transmission within the cat population warrants further studies.

Non-hormonal Clitoromegaly due to Clitoral Priapism Caused by Appendicitis/Appendectomy

Clitoromegaly usually develops due to hyperandrogenism. There are a few cases of clitoromegaly described without clinical and biochemical hyperandrogenism. Clitoromegaly due to clitoral priapism and clitoral priapism after appendectomy have not been reported previously. A 7-year-old girl was referred for enlargement of the clitoris. She reported having a mild, pulsating clitoral pain starting three days after an appendectomy operation. Subsequently, painful swelling and an increase in the size of the clitoris was observed. Her growth and physical examination were otherwise normal. Causes of the clitoromegaly due to androgen excess were excluded after a comprehensive work-up. Color Doppler ultrasound revealed a high peak systolic velocity and resistance in the cavernosal artery, consistent with clitoral priapism. The clitoromegaly and associated symptoms improved significantly with oral pseudoephedrine and intracavernosal aspiration. This unique case illustrates that clitoral priapism is a rare, non-hormonal cause of clitoromegaly and may occur after appendectomy. Pseudoephedrine treatment is helpful in alleviating the symptoms.

Exposure to Biological Fluids in Dental Practice-Narrative Review on Appropriate Risk Assessment to Guide Post-Exposure Management

Accidental exposure to blood or other biological fluids is a common occurrence in dentistry, and its post-exposure management is a key component of infection prevention and control programs designed to prevent the transmission of blood-borne pathogens such as hepatitis B and C viruses (HBV, HCV) and human immunodeficiency virus (HIV). This narrative review aims to comprehensively review the risk assessment process for each of these pathogens at all steps of the epidemiological process, i.e., source-exposure route-receptive person, in order to provide a better understanding of the delicate differences that influence the transmission risk and that drive the individualized post-exposure management.

Horizontal transmission might be a common route of hepatitis B virus exposure in highly endemic areas

BACKGROUND AND AIMS

Hepatitis B virus (HBV) is a common viral pathogen that infects more than a third of the world's population; however, the transmission route remains to be further defined. The 18-year implementation of free HBV vaccine for children has greatly changed the prevalence of HBV infection in China, which presents a unique real-world model for assessing the pattern of HBV transmission.

METHODS

Cross-sectional data of HBV seromarkers between July 2019 and April 2020 were collected from 53,371 individuals aged 1-60 years in four areas of North to South in Eastern China. Longitudinal data of HBV seromarkers between 2007 and 2020 were collected from 177 adults in an area of South China. The regional- and age-specific changes in HBV seromarkers were analyzed.

RESULTS

Overall, positive rates of HBV surface antigen (HBsAg) (from 3.44% to 15.1%) and antibody against HBV core antigen (anti-HBc) (from 7.6% to 44.0%) significantly increased from North to South. Among persons aged ≤18 years, the positive rates of antibody against HBsAg (anti-HBs) and anti-HBc (+) remained at low levels in the North, while they were increasing among persons aged >12 years in the South, despite higher positive rates of anti-HBs (+). Among persons aged >18 years, the anti-HBs (+) rates remained relatively stable (~60%), while anti-HBc (+) rates increased significantly with age. Up to ~80% of the anti-HBs (+) adults in the South was anti-HBc (+) while it was 13.6% in the North. In the longitudinal cohort, the anti-HBc (+) rate among adults in the South increased by 14.2% during 10 years of follow-up.

CONCLUSION

Horizontal transmission might be a common route in highly endemic areas, and may help to explain the high HBV exposure worldwide. The risk of horizontal transmission among children without seroprotective anti-HBs should be notified in highly endemic areas. This article is protected by copyright. All rights reserved.

Viruses, periodontitis, and comorbidities

Seminal studies published in the 1990s and 2000s explored connections between periodontal diseases and systemic conditions, revealing potential contributions of periodontal diseases in the initiation or worsening of systemic conditions. The resulting field of periodontal medicine led to the publication of studies indicating that periodontal diseases can influence the risk of systemic conditions, including adverse pregnancy outcomes, cardiovascular and respiratory diseases, as well as Alzheimer disease and cancers. In general, these studies hypothesized that the periodontal bacterial insult and/or the associated proinflammatory cascade could contribute to the pathogenesis of these systemic diseases. While investigations of the biological basis of the connections between periodontal diseases and systemic conditions generally emphasized the bacteriome, it is also biologically plausible, under an analogous hypothesis, that other types of organisms may have a similar role. Human viruses would be logical "suspects" in this role, given their ubiquity in the oral cavity, association with periodontal diseases, and ability to elicit strong inflammatory response, compromise immune responses, and synergize with bacteria in favor of a more pathogenic microbial consortium. In this review, the current knowledge of the role of viruses in connecting periodontal diseases and systemic conditions is examined. We will also delve into the mechanistic basis for such connections and highlight the importance of those relationships in the management and treatment of patients.

Variable Proportions of Phylogenetic Clustering and Low Levels of Antiviral Drug Resistance among the Major HBV Sub-Genotypes in the Middle East and North Africa

Hepatitis B virus (HBV) infection remains a major public health threat in the Middle East and North Africa (MENA). Phylogenetic analysis of HBV can be helpful to study the putative transmission links and patterns of inter-country spread of the virus. The objectives of the current study were to analyze the HBV genotype/sub-genotype (SGT) distribution, reverse transcriptase (RT), and surface (S) gene mutations and to investigate the domestic transmission of HBV in the MENA. All HBV molecular sequences collected in the MENA were retrieved from GenBank as of 30 April 2021. Determination of genotypes/SGT, RT, and S mutations were based on the Geno2pheno (hbv) 2.0 online tool. For the most prevalent HBV SGTs, maximum likelihood phylogenetic analysis was conducted to identify the putative phylogenetic clusters, with approximate Shimodaira-Hasegawa-like likelihood ratio test values ≥ 0.90, and genetic distance cut-off values ≤ 0.025 substitutions/site as implemented in Cluster Picker. The total number of HBV sequences used for genotype/SGT determination was 4352 that represented a total of 20 MENA countries, with a majority from Iran (n = 2103, 48.3%), Saudi Arabia (n = 503, 11.6%), Tunisia (n = 395, 9.1%), and Turkey (n = 267, 6.1%). Genotype D dominated infections in the MENA (86.6%), followed by genotype A (4.1%), with SGT D1 as the most common in 14 MENA countries and SGT D7 dominance in the Maghreb. The highest prevalence of antiviral drug resistance was observed against lamivudine (4.5%) and telbivudine (4.3%). The proportion of domestic phylogenetic clustering was the highest for SGT D7 (61.9%), followed by SGT D2 (28.2%) and genotype E (25.7%). The largest fraction of domestic clusters with evidence of inter-country spread within the MENA was seen in SGT D7 (81.3%). Small networks (containing 3-14 sequences) dominated among domestic phylogenetic clusters. Specific patterns of HBV genetic diversity were seen in the MENA with SGT D1 dominance in the Levant, Iran, and Turkey; SGT D7 dominance in the Maghreb; and extensive diversity in Saudi Arabia and Egypt. A low prevalence of lamivudine, telbivudine, and entecavir drug resistance was observed in the region, with almost an absence of resistance to tenofovir and adefovir. Variable proportions of phylogenetic clustering indicated prominent domestic transmission of SGT D7 (particularly in the Maghreb) and relatively high levels of virus mobility in SGT D1.

Applicability of oral fluid samples for tracking hepatitis B virus mutations, genotyping, and phylogenetic analysis

Little is known about the usefulness of saliva samples for hepatitis B virus (HBV) genotyping and mutation analysis. The aim of this study was to evaluate the usefulness of oral fluid samples to determine HBV genotype distribution, S/polymerase mutations, and HBV subpopulation diversity among chronically HBV-infected individuals. Serum and oral fluid samples were obtained from 18 individuals for PCR and nucleotide sequencing of the HBV surface antigen gene. Biochemical analysis of liver enzymes (ALT, AST, GGT) and HBV, HCV, and HIV serological tests were also performed. All serum samples were HBsAg (+), anti-HBc (+), and anti-HBs (-); 55.6% were HBeAg (+)/anti-HBe (-), and 11.1% were anti-HIV (+). The mean HBV DNA viral load was 6.1 ± 2.3 log IU/mL. The HBV genotype distribution was as follows: A, 72.2%; D, 11.1%; E, 5.6%; F, 11.1%. A concordance of 100% in genotype classification and 99.8% in sequence similarity between paired oral fluid and serum samples was observed. HBsAg mutations were detected in all samples, but no resistance mutations were found in the polymerase gene. This study demonstrates that oral fluid samples can be used reliably for tracking HBV mutations, genotyping, and phylogenetic analysis. This could be important for molecular epidemiology studies with hard-to-reach populations.

Molecular Mechanisms during Hepatitis B Infection and the Effects of the Virus Variability

The immunopathogenesis and molecular mechanisms involved during a hepatitis B virus (HBV) infection have made the approaches for research complex, especially concerning the patients’ responses in the course of the early acute stage. The study of molecular bases involved in the viral clearance or persistence of the infection is complicated due to the difficulty to detect patients at the most adequate points of the disease, especially in the time lapse between the onset of the infection and the viral emergence. Despite this, there is valuable data obtained from animal and in vitro models, which have helped to clarify some aspects of the early immune response against HBV infection. The diversity of the HBV (genotypes and variants) has been proven to be associated not only with the development and outcome of the disease but also with the response to treatments. That is why factors involved in the virus evolution need to be considered while studying hepatitis B infection. This review brings together some of the published data to try to explain the immunological and molecular mechanisms involved in the different stages of the infection, clinical outcomes, viral persistence, and the impact of the variants of HBV in these processes.

A longitudinal observational study in two cats naturally-infected with hepadnavirus

Hepatitis B virus (HBV) is a major cause of liver disease in humans including chronic hepatitis and hepatocellular carcinoma. Domestic cat hepadnavirus (DCH), a novel HBV-like hepadnavirus, was identified in domestic cats in 2018. From 6.5 %-10.8 % of pet cats are viremic for DCH and altered serological markers suggestive of liver damage have been identified in 50 % of DCH-infected cats. DCH DNA has been detected in association with characteristic lesions of chronic hepatitis and with hepatocellular carcinoma in cats, suggesting a possible association. In this study longitudinal molecular screening of cats infected with DCH was performed to determine if DCH can cause chronic infections in cats. Upon re-testing of sera from five DCH-positive animals, 2-10 months after the initial diagnosis, three cats tested negative for DCH on two consecutive occasions using quantitative PCR. Two other cats remained DCH-positive, including an 8-month-old female cat re-tested four months after the initial positive result, and a 9-year-old male cat, which tested positive for DCH on six occasions over an 11-month period. The latter had a history of chronic hepatopathy with jaundice, lethargy and elevated serum alanine transaminase levels (ALT). During the period of observation, DCH titers ranged between 1.64 × 10⁵ and 2.09 × 10⁶ DNA copies/mL and ALT was persistently elevated, suggesting chronic infection. DCH DNA was not detected in oral, conjunctival, preputial and rectal swabs from the two animals collected at several time points. Long-term (chronic) infection would be consistent with the relatively high number of viremic cats identified in epidemiological investigations, with the possible association of DCH with chronic hepatic pathologies and with what described with HBV in human patients.

Seroprevalence of hepatitis B virus: Findings from a population-based household survey in KwaZulu-Natal, South Africa

Background:

Hepatitis B virus (HBV) infection is a major cause of morbidity and mortality; however, little is known about the prevalence and distribution of HBV in some populations and regions.

Methods:

A total of 9791 participants, 15–49 years old, were enrolled in a household survey in KwaZulu-Natal, South Africa. Peripheral blood samples were tested for markers of HBV (hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), antibody to HBeAg (anti-HBe)) and analysed, accounting for multilevel sampling and weighted to represent the population.

Results:

Overall HBsAg prevalence was 4.0% (95% confidence interval (CI) 3.4–4.5%): 4.8% (95% CI 3.8–5.8%) in men and 3.2% (95% CI 2.5–3.9%) in women (p = 0.01). Among HBsAg-positive participants, 35.2% (95% CI 29.2–41.2%) were HBeAg-positive and 66.3% (95% CI 60.1–72.4%) were anti-HBe-positive. HBsAg prevalence was 6.4% (95% CI 5.3–7.5%) among HIV-positive participants compared to 2.6% (95% CI 1.9–3.2%) among HIV-negative participants (p < 0.01), and was higher among HIV-positive men (8.7%, 95% CI 6.3–11.2%) than among HIV-positive women (5.0%, 95% CI 3.8–6.2%) (p < 0.01).

Conclusions:

HBV infection among HIV-positive men remains an important public health problem in communities in KwaZulu-Natal, South Africa. The prevalence of HBsAg and HBeAg highlight the importance of surveillance and an important missed opportunity for the scale-up of programmes to achieve the goal of controlling HBV for public health benefit.

Applicability of Oral Fluid and Dried Blood Spot for Hepatitis B Virus Diagnosis

Hepatitis B virus (HBV) is one of the major causes of chronic liver disease worldwide; however most of individuals are not aware about the infection. Oral fluid and dried blood spot (DBS) samples may be an alternative to serum to HBV diagnosis to increase the access to diagnosis in remote areas or high-risk groups. The main objective of this review is to give an insight about the usefulness of oral fluid and DBS for detecting HBV markers. Several groups have evaluated the detection of HBsAg, anti-HBc, and anti-HBs markers in oral fluid and DBS samples demonstrating 13 to 100% of sensitivity and specificity according different groups, sample collectors, and diagnosis assays. In the same way, HBV DNA detection using oral fluid and DBS samples demonstrate different values of sensitivity according type of collection, studied group, extraction, and detection methods. Thus, serological and molecular diagnostic tests demonstrated good performance for detecting HBV using oral fluid and DBS according some characteristics and could be useful to increase the access to the diagnosis of HBV.

Correlates of hepatitis B awareness and disease-specific knowledge among pregnant women in Northern and Central Uganda: a cross-sectional study

Introduction

Countries in sub-Saharan Africa with a high hepatitis B burden also have limited resources to identify underlying drivers of disease among key at-risk populations. To improve prioritization and strengthen prevention of mother to child transmission of HBV, it is imperative to understand disease awareness, knowledge and related factors among pregnant women.

Objectives

This study assessed HBV disease awareness, knowledge and related factors among pregnant women in public health facilities in two regions with diverse HBV disease epidemiology.

Methods

From October 2016 through December 2017, a random sample of 455 pregnant women attending antenatal clinics were surveyed to assess HBV awareness, knowledge and associated factors. Participants responded to an 18-item questionnaire with themes on HBV awareness, knowledge of disease signs and symptoms, transmission, prevention and misconceptions about the disease. Results were analysed in STATA (version 14.0).

Results

Of 455 participants enrolled, about two thirds reported having heard about HBV disease. By region, nearly half (47%) of participants from the central region, compared to only 16% from the north, reported that they had never heard of HBV. Region of residence had a moderating effect on the education- HBV awareness relationship. Only 162/455 (36%) of participants had adequate HBV knowledge. More than half 256/455 (56%) and 242/455 (53%) were not knowledgeable about horizontal and mother to child HBV transmission, respectively. About two thirds 298/455 (66%) and 281/455 (62%) believed HBV was spread via sharing of utensils and mosquito bites respectively. In multiple regression analysis, residing in the north, (PR=1.91(1.53 -2.38), p < 0.001) compared to central region and having a secondary education (PR=1.87(1.37 -2.55), p < 0.001) compared to primary were statistically significantly related to being knowledgeable about HBV.

Conclusion

We demonstrated marked regional differences in HBV disease awareness and knowledge in this high HBV prevalence setting. However, most pregnant women displayed unacceptably low HBV knowledge and a significant proportion still hold misconceptions about HBV. Interventions to improve HBV prevention through antenatal education will need to be tailored to existing differences in comprehensive HBV knowledge.

Viral Biomarkers in Chronic HBeAg Negative HBV Infection

Viral biomarkers are important tools for monitoring chronic hepatitis B virus (HBV) hepatitis B early antigen (HBeAg) negative infection, both in its natural course as well as during and after treatment. The biomarkers consist of antibodies against viral epitopes, viral proteins, and molecular surrogate markers of the quantity and transcriptional activity of the stable episomal HBV covalently closed circular DNA (cccDNA) which is located in the nuclei of the infected hepatocytes. HBV deoxyribonucleic acid (DNA) or else viral load measurement in plasma or serum is a marker of HBV replication of major clinical importance. HBV DNA is used for staging and treatment monitoring as described in international scientific guidelines. Quantification of HBV antigens, mainly hepatitis B surface antigen (HBsAg) as well as Hepatitis B core related antigen (HBcrAg), play an important yet secondary role, especially in cases of low or undetectable HBV DNA and has been evaluated for the classification of the inactive carrier state, as a predictor of subsequent HBsAg clearance, treatment outcome, and development of hepatocellular carcinoma (HCC). The measurement of the replicative intermediate HBV RNA in serum is currently evaluated and may also prove to be a significant biomarker particularly in patients treated with nucleot(s)ide analogs. This review focuses on the viral biomarkers mentioned above and their role in HBV, HBeAg negative, infection.

Usefulness of in-house real time PCR for HBV DNA quantification in serum and oral fluid samples

For quantification of hepatitis B virus DNA (HBV DNA), commercial assays are used with serum or plasma samples, but oral fluid samples could be an alternative for HBV diagnosis due to ease of collection. This study aims to develop in-house real time PCR using synthetic curve for HBV DNA quantification for serum and oral fluid samples. Samples were collected from 103 individuals (55 HBsAg reactive and HBV DNA reactive by commercial assay and 48 without HBV markers) and submitted to two in-house real time PCR assays for HBV pre-S/S region with different standard curves: qPCR plasmidial and qPCR synthetic. A total of 27 serum samples were HBV DNA positive by qPCR plasmidial and 40 with qPCR synthetic (72% and 85% of concordance, respectively). Quantitative PCR synthetic presented efficiency of 99% and sensitivity of 2log10 copies/mL. Among oral fluid samples, five and ten were detected using qPCR plasmidial and synthetic, respectively. This study demonstrated that qPCR synthetic using serum samples could be used as alternative for HBV DNA quantification due to its sensitivity. In addition, it was possible to quantify HBV DNA in oral fluid samples suggesting the potential of this specimen for molecular diagnosis of HBV.

Detection of occult hepatitis B in serum and oral fluid samples

In occult hepatitis B infection (OBI), hepatitis B virus DNA (HBV DNA) can be detected in serum samples; however, oral fluid collection for detection of HBV DNA has not yet been explored, despite the availability of collection devices. Serum and oral fluid samples from 45 hepatitis B core antibody (anti-HBc)-positive patients were collected for the amplification of the HBV polymerase gene. HBV DNA was detected in five serum and four oral fluid samples (the detection limit for oral fluid was 1.656 log IU/mL in paired serum). In conclusion, simple methodologies of sample collection and in-house polymerase chain reaction (PCR) allowed detection of HBV DNA, and these could be used to improve the diagnosis of OBI, especially in locations with limited resources.

Comparison of oral fluid collection methods for the molecular detection of hepatitis B virus

BACKGROUND

This study aims to compare the efficiency of four oral fluid collection methods (Salivette, FTA Card, spitting and DNA-Sal) to detect HBV DNA by qualitative PCR.

MATERIALS AND METHODS

Seventy-four individuals (32 HBV reactive and 42 with no HBV markers) donated serum and oral fluid. In-house qualitative PCR to detect HBV was used for both samples and commercial quantitative PCR for serum.

RESULTS

HBV DNA was detected in all serum samples from HBV-infected individuals, and it was not detected in control group. HBV DNA from HBV group was detected in 17 samples collected with Salivette device, 16 samples collected by FTA Card device, 16 samples collected from spitting and 13 samples collected by DNA-Sal device. Samples that corresponded to a higher viral load in their paired serum sample could be detected using all oral fluid collection methods, but Salivette collection device yielded the largest numbers of positive samples and had a wide range of viral load that was detected.

CONCLUSION

It was possible to detect HBV DNA using all devices tested, but higher number of positive samples was observed when samples were collected using Salivette device, which shows high concordance to viral load observed in the paired serum samples.

Saliva: a reliable sample matrix in bioanalytics

Saliva is gaining increasing attention as a bioanalytical sample matrix. Mostly because of the easy and noninvasive collection, it is not only beneficial in endocrinological and behavioral science, but also in pediatrics. Saliva also has the advantage of being the only body fluid which can be collected even during physical exercise, for example, during sportive activities, and there are physiological characteristics that make it superior to serum/plasma or urine for specific scientific questions. This review provides an insight into the physiology of saliva formation, explaining how certain compounds enter this bodily fluid, and gives advice for collection, storage and analytical methods. Finally, it presents a number of reliable and proven applications for saliva analysis from scientific fields including endocrinology, sports medicine, forensics and immunology.

Characteristics and course of chronic hepatitis B e antigen-negative infection

OBJECTIVE

To describe the epidemiological, analytical and histological characteristics and clinical course of hepatitis B virus (HBV) carriers with negative HBe antigen.

MATERIAL AND METHODS

Observational, retrospective cohort study of HBV carriers with negative HBe antigen (2005-2012), with no other causes of liver disease.

RESULTS

One hundred and thirty-eight patients were included, with mean age 40.5±12.2 years; 54% were women, and 38% were of foreign origin; the number of foreign patients significantly increased (P<.001) over the years. Transaminases were normal in nearly 75% and HBV-DNA was <2,000IU/ml in 56% of patients at diagnosis. There was a gradual decrease in HBV-DNA levels in inactive carriers over the study period. Fibrosis study was performed in 47% of patients by Fibroscan^® or liver biopsy: 55.4% normal histology and 6.1% cirrhosis. Just over three quarters of patients (77.77%) were inactive carriers. Treatment was required in 15.5% of patients (20% because of cirrhosis and 80% HBeAg-negative chronic hepatitis B). Five patients cleared HBsAg (annual rate .94%), all of whom presented HBV-DNA <2,000IU/ml at diagnosis. Five patients developed complications (3.6%), 4 of them hepatocellular carcinoma (HCC), of which only 2 had cirrhosis. There was 1 HBV-related death (.72%).

CONCLUSION

Among HBV carriers with negative HBe antigen, inactive HBs-Ag carriers are predominant. HBV-DNA gradually decreases in the first few years after diagnosis. Morbidity and mortality are low, especially if glutamic pyruvic transaminase (GPT) is normal and HBV-DNA levels are low at diagnosis. Treatment is needed in a considerable number of patients. HCC is the most frequent complication, even in the absence of cirrhosis.

The Role of Body Fluids in the Horizontal Transmission of Hepatitis B Virus via Household/Close Contact

Hepatitis B virus (HBV) infection commonly occurs through horizontal transmission via household/close contact. Although the body fluids of patients infected with HBV are likely to play a significant role in horizontal transmission, the precise mechanism remains unclear. In the 1970s, the infectivity of body fluids including saliva, urine, and faeces was assessed for the presence of hepatitis B surface antigen (HBsAg). Over the last decade, the HBV DNA in the body fluids of chronically infected patients was quantified using real-time polymerase chain reaction. Chimpanzee, gibbon, and chimeric mice with human livers have also been used to investigate the infectivity of body fluids. HBsAg levels, HBV DNA levels, and animal experiments have indicated that saliva and tears are able to transmit HBV. Urine and faeces do not lead to horizontal transmission. The infectivity of the remaining body fluids remains controversial. Horizontal transmission is related to both virus and host factors; thus, evaluations of HBsAg and HBV DNA levels provide insufficient data to determine the infectivity of body fluids. Universal hepatitis B vaccination has been implemented worldwide (with the exception of Northern Europe); an understanding of the role that body fluids play in horizontal transmission will contribute to the eradication of HBV.

Epidemiological and molecular features of hepatitis B and hepatitis delta virus transmission in a remote rural community in central Africa

Hepatitis B virus (HBV) and hepatitis delta virus (HDV) occur worldwide and are prevalent in both urban and remote rural communities. In a remote village in Gabon, central Africa, we observed a high prevalence of HBsAg carriage and HDV infection, particularly in children and adolescents. The prevalence of HBsAg differed significantly by gender and age, females being more likely than males to carry the HBsAg during the first 10 years of life, while the prevalence was higher among males than females aged 11-20 years. We also characterised HBV and HDV strains circulating in the village. The principal HBV strains belonged to genotype HBV-E and subgenotype QS-A3. Complete genome analysis revealed for the first time the presence of the HBV-D genotype in Gabon, in the form of an HBV-D/E recombinant. Molecular analysis of HDV strains and their complete genomic characterisation revealed two distinct groups within the dominant HDV clade 8. Molecular analysis of HBV and HDV strains did not reveal vertical transmission within the families studied but rather horizontal, intrafamilial transmission among children aged 0-10 years. Our findings indicate that HBV is transmitted in early childhood by body fluids rather than by sexual contact. Health education adapted to the different age groups might therefore help to reduce HBV transmission. Young children should be vaccinated to control HBV infection in areas of extremely high prevalence.

Update on hepatitis B and C virus diagnosis

Viral hepatitis B and C virus (HBV and HCV) are responsible for the most of chronic liver disease worldwide and are transmitted by parenteral route, sexual and vertical transmission. One important measure to reduce the burden of these infections is the diagnosis of acute and chronic cases of HBV and HCV. In order to provide an effective diagnosis and monitoring of antiviral treatment, it is important to choose sensitive, rapid, inexpensive, and robust analytical methods. Primary diagnosis of HBV and HCV infection is made by using serological tests for detecting antigens and antibodies against these viruses. In order to confirm primary diagnosis, to quantify viral load, to determine genotypes and resistance mutants for antiviral treatment, qualitative and quantitative molecular tests are used. In this manuscript, we review the current serological and molecular methods for the diagnosis of hepatitis B and C.

Nosocomial outbreak of hepatitis B virus infection in a pediatric hematology and oncology unit in South Africa: Epidemiological investigation and measures to prevent further transmission

BACKGROUND

Hospital-acquired hepatitis B virus (HBV) infection has been well described and continues to occur worldwide. Recent nosocomial outbreaks have been linked to unsafe injection practices, use of multi-dose vials, and poor staff compliance with standard precautions. This report describes a nosocomial outbreak that occurred in a pediatric hematology and oncology unit of a large academic hospital, the epidemiological investigation of the outbreak, and preventive measures implemented to limit further in-hospital transmission.

METHODS

Outbreak investigation including contact tracing and HBV screening were initially carried out on all patients seen by the unit during the same period as the first three cases. Routine screening for the entire patient population of the unit was initiated in February 2013 when it was realized that numerous patients may have been exposed.

RESULTS

Forty-nine cases of HBV infection were confirmed in 408 patients tested between July 2011 and October 2013. Phylogenetic analysis of the HBV preC/C gene nucleotide sequences revealed that all tested outbreak strains clustered together. Most (67%) patients were HBeAg positive. The cause of transmission could not be established. Preventive measures targeted three proposed routes. HBV screening and vaccination protocols were started in the unit.

CONCLUSIONS

The high number of HBeAg positive patients, together with suspected lapses in infection prevention and control measures, are believed to have played a major role in the transmission. Measures implemented to prevent further in-hospital transmission were successful. On-going HBV screening and vaccination programs in pediatric hematology and oncology units should become standard of care.

Knowledge of and risky behaviours towards hepatitis B virus infection among Egyptian school children

BACKGROUND AND STUDY AIMS

Success in the prevention of hepatitis B virus (HBV) depends to a large extent on the adolescents' HBV knowledge and their risky behaviours. This study aims to assess the knowledge of and the risky behaviours towards HBV among school students and to determine the significant predictors affecting their knowledge.

PATIENTS AND METHODS

A cross-sectional study was approved in four Egyptian governorates (Dakahleya, Gharbeya, Cairo, and Beni-Suef) on 574 students aged 11-17years. A questionnaire was filled through a face-to-face interview to collect data about the socio-demographic character, HBV knowledge, and risky behaviours among children who were chosen for this study.

RESULTS

While 75% of students had poor levels of HBV knowledge, 1.7% had good levels of knowledge. As regards gender, more than 60% of students shared scissors and went to dental clinic with no significant difference. While boys reported a significant history of hospitalisation (50.2%) and wound stitches (36%), girls reported a lesser degree of the same (40.2% and 22.6, respectively), p<0.01. During logistic regression analysis, the most important predictors of poor HBV knowledge were age <15years and living in Cairo governorate, with adjusted odds ratio (AOR) 1.5 and 5.0, respectively.

CONCLUSION

The majority of students chosen for the study had low levels of knowledge and high risky behaviours towards viral hepatitis. In order to minimise the risky behaviours among adolescents, health education programmes should be conducted concerning the mode of transmission and prevention of viral hepatitis.

Lack of infectivity of HBV in feces from patients with chronic hepatitis B virus infection, and infection using chimeric mice

BACKGROUND

Body fluids such as saliva and tears from patients with hepatitis B virus (HBV) infection are known as infectious agents. The infectivity of feces from patients with HBV infection has not been established. The aim of this study was to determine whether feces from HBV carriers can be a source of HBV infection.

METHODS

Thirty-three children and 17 adults (ages 0-49 years, median age 13 years) who were chronically infected with HBV were enrolled. The levels of HBV DNA in the feces from these patients were quantified by real-time PCR, and the levels of fecal HBsAg were measured. Isolated human hepatocytes from chimeric mice with humanized livers were co-cultured with serum, tears and feces from the HBV carriers. Four chimeric mice were inoculated intravenously with sterilized feces from HBV carriers.

RESULTS

HBV DNA was detected in the feces of 37 (74%) of the 50 patients. The fecal HBV DNA levels ranged from 2.8 to 8.4 log copies/mL (mean ± SD  =  5.6 ± 1.2 log copies/mL). A significant correlation was observed in the levels of HBV DNA between serum and feces (r  =  0.54, p < 0.05). Of the 13 HBV carries, 7 (54%) were positive for fecal HBsAg. The fecal HBsAg levels ranged from 0.06 to 1.0 IU/mL (median 0.28 IU/mL). Immunogold electron microscopy showed Dane particles in feces. HBV DNA was detected in the human hepatocytes co-cultured with serum and tears, but not in those co-cultured with feces. HBV DNA was not detected in the serum of the chimeric mice after oral or intravenous inoculation with sterilized fecal samples, which contained 5 log copies/mL of HBV DNA levels.

CONCLUSIONS

Although the positive rate of fecal HBV DNA was high, the fecal HBsAg levels were extremely low. The chimeric mice were not infected with HBV after oral or intravenous inoculation with sterilized fecal samples. Therefore, feces from HBV carriers seem not to serve as an infectious vehicle for the transmission of HBV.

Sequential occurrence of acute hepatitis B among members of a high school Sumo wrestling club

A 17-year-old male was admitted to our hospital and diagnosed with acute hepatitis B. Six weeks later, a 15-year-old male was admitted with acute hepatitis B as well. They were Sumo wrestling players in the same club. A detailed survey in the club revealed that a 28-year-old male coach was a hepatitis B surface antigen carrier with high-level viremia. The consistency of hepatitis B virus (HBV) DNA in the infected players was revealed by analyzing the complete HBV genome sequences. Sumo players are more likely to get injured, including cuts and bleeding, compared with players of other sports because of the characteristic wrestling style. Several past reports have suggested that highly viremic HBV carriers have high HBV DNA titers in both their blood and other body fluids such as sweat. In our cases, percutaneous HBV transmission through the bleeding wounds was the most probable infection route. We conclude that a universal HBV immunization program should be introduced urgently in Japan, similar to those implemented in other countries worldwide.

Saliva specimen sampling: a noninvasive method for diagnosis and basic investigation of viral hepatitis A, B and C

Saliva is a biological fluid that is easy to collect and manipulate. Collection of saliva samples is less expensive, noninvasive and painless compared with blood collection. Due to these advantages, saliva has been investigated as an alternative fluid to serum for diagnostic and epidemiological purposes. The aim of this article was to the review research on salivary biomarkers of viral hepatitis A, B and C, highlighting their current use, collection devices, and potential applications for diagnosis and epidemiological studies. This paper also explores recent findings of saliva as a possible source of viral hepatitis transmission.

Detecting viruses by using salivary diagnostics

BACKGROUND

Diagnostics that involve the use of oral fluids have become increasingly available commercially in recent years and are of particular interest because of their relative ease of use, low cost and noninvasive collection of oral fluid for testing.

TYPES OF STUDIES REVIEWED

The authors discuss the use of salivary diagnostics for virus detection with an emphasis on rapid detection of infection by using point-of-care devices. In particular, they review salivary diagnostics for human immunodeficiency virus, hepatitis C virus and human papillomavirus. Oral mucosal transudate contains secretory immunoglobulin (Ig) A, as well as IgM and IgG, which makes it a good source for immunodiagnostic-based devices.

CLINICAL IMPLICATIONS

Because patients often visit a dentist more regularly than they do a physician, there is increased discussion in the dental community regarding the need for practitioners to be aware of salivary diagnostics and to be willing and able to administer these tests to their patients.

An update after 16 years of hepatitis B vaccination in South Africa

Hepatitis B (HB) virus (HBV) infection is highly endemic with at least 65 million chronic HB surface antigen (HBsAg) carriers in Africa, 25% of whom are expected to die from liver disease. Before the introduction of the HB vaccine, the prevalence of chronic carriage of HBV in black South Africans was 9.6%, with 76% having been previously exposed to HBV. The major transmission route in South Africa is unexplained horizontal transmission between toddlers, with most transmission occurring before the age of 5 years. During adolescence and early adulthood, sexual transmission becomes the dominant route, while healthcare workers (HCWs) are also at risk for parenteral/percutaneous transmission during occupational exposures. In 1995 the South African Department of Health (SADoH) incorporated the HB vaccine, administered as a monovalent, into the Expanded Programme on Immunisation (EPI) at 6, 10, and 14 weeks of age, and studies conducted thereafter have found it to be safe and highly effective. Catch-up vaccination for adolescents was not introduced and there is no schools-based vaccination programme. The SADoH recommends HB vaccination of HCWs, but this is not mandatory and there is no national policy, thus HB vaccination uptake in HCWs is sub-optimal. Since 1995, studies on children have found that the prevalence of chronic HBsAg carriage has decreased, as has the incidence of paediatric hepatocellular carcinoma and HBV-related membranous nephropathy. The SADoH should focus their efforts on attaining a high infant HB vaccine coverage, prepare for introducing a HB birth dose, and consider using a hexavalent vaccine (DTaP-IPV-Hib-HepB). The department may also want to consider including targeted HB vaccination for 12 year-olds, if their Road to Health Cards show they were not vaccinated as infants. A national policy is needed for HCWs to ensure that they are fully vaccinated and protected against HBV infection.

Deficient knowledge on hepatitis B infection in pregnant women and prevalence of hepatitis B surface antigen carriage in an endemic area: a review

Hepatitis B infection is a major global health problem. Vertical transmission is the commonest route of spreading hepatitis B virus (HBV) in many endemic areas. In order to control such transmission in Hong Kong, neonatal immunization programme was implemented for more than two decades. A declining prevalence of HBV infection was expected. However, the prevalence remained unabated at around 10% in recent studies. We suspect that one of the explanations of this persistent high prevalence is deficient knowledge on infection with the HBV and its prevention. Our paper gives an overview of the knowledge on HBV infection among Chinese population in both high and low endemic areas and discusses the potential factors that influenced the knowledge on as well as the implication of the sources of information for HBV infection, which was not addressed in previous studies.

Tears from children with chronic hepatitis B virus (HBV) infection are infectious vehicles of HBV transmission: experimental transmission of HBV by tears, using mice with chimeric human livers

BACKGROUND

Body fluids such as saliva, urine, sweat, and tears from hepatitis B virus (HBV) carriers are potential sources of HBV transmission.

METHODS

Thirty-nine children and 8 adults who were chronically infected with HBV were enrolled. Real-time polymerase chain reaction was used for the quantification of HBV DNA.

RESULTS

HBV DNA was detected in 73.7% of urine samples (14 of 19), 86.8% of saliva samples (33 of 38), 100% of tear samples (11 of 11), and 100% of sweat samples (9 of 9). Mean HBV DNA levels (±SD) in urine, saliva, tears, and sweat were 4.3 ± 1.1 log copies/mL, 5.9 ± 1.2 log copies/mL, 6.2 ± 0.7 log copies/mL, and 5.2 ± 0.6 log copies/mL, respectively. A statistically significant correlation was observed between the HBV DNA level in serum specimens and HBV DNA levels in saliva and tear specimens (r = 0.88; P < .001). Tear specimens from a child were injected intravenously into 2 human hepatocyte-transplanted chimeric mice. One week after inoculation, both chimeric mice had serum positive for HBV DNA.

CONCLUSIONS

The levels of HBV DNA in tear specimens from young children were high. Tears were confirmed to be infectious, using chimeric mice. Strict precautions should be taken against direct contact with body fluids from HBV carriers with high-level viremia.

A comparison of molecular methods for hepatitis B virus (HBV) DNA detection from oral fluid samples

The objective of the present study was to evaluate four commercial DNA extraction methods and three PCR protocols for hepatitis B virus (HBV) detection in artificially contaminated oral fluid samples. The extraction protocols were selected based on ease of use and cost, and were also compared with respect to sensitivity and cost. Prior PCR optimization was conducted, in which the sample volume for DNA extraction and the concentrations of DNA and Taq DNA polymerase in the PCR were adjusted. One-round PCR, used to amplify the core region of the HBV genome, achieved high levels of sensitivity in comparison with nested and semi-nested PCR experiments that were designed for the amplification of HBV surface protein genes. Of the four extraction protocols evaluated, the RTP DNA/RNA Virus Mini kit and the QIAamp DNA Mini kit gave the highest recovery rates, presenting 20 copies of HBV DNA ml(-1) as the limit of detection. These results suggest that HBV DNA can be detected from oral fluid samples but that the optimization of the PCR assays and the choice of extraction methods must be determined by laboratories before the implementation of this method in routine diagnostics.

Oral fluid and hepatitis A, B and C: a literature review

BACKGROUND AND AIMS

Viral hepatitis is a significant global health problem that, depending upon the virus, affects individuals of the developing and/or developed world. In recent years, there has been renewed interest in whether oral fluids can be considered as a source of viral hepatitis transmission and whether oral fluid, in particular, whole saliva, may be a useful source for viral detection as part of the diagnosis and monitoring of viral hepatitis. The aim of this article was to review current data concerning the possible carriage of the hepatitis A, B and C viruses within saliva and gingival crevicular fluid. Such knowledge will indicate if (i) oral fluid is a possible source of infection and (ii) whether oral fluid can be used for diagnosis and monitoring of viral hepatitis.

DATA AND SOURCES

A literature search was conducted using PubMed (Medline), EMBASE/Excerpta medica, the Cochrane database and Scopus. The results were limited to published material after 2000. Relevant material was evaluated and reviewed.

CONCLUSION

There is some evidence that hepatitis viruses A, B and C are present in oral fluids, particularly whole saliva and gingival crevicular fluid and may thus be possible sources of viral detection in clinical diagnosis and monitoring. However, the data are inconsistent and warrant the need for well-planned longitudinal studies to explore the precise frequency of oral carriage of such viruses and to determine the virological and host factors that may influence the oral presence of hepatitis A, B and C viruses.

Non-invasive screening of HLA-DPA1 and HLA-DPB1 alleles for persistent hepatitis B virus infection: susceptibility for vertical transmission and toward a personalized approach for vaccination and treatment

BACKGROUND

Polymorphisms in the major histocompatibility complex (MHC) and non-MHC genes were recently reported to be associated with persistent hepatitis B virus (HBV) infection and host response to hepatitis B vaccine in Asian populations. We aimed to confirm the associations in Chinese population and develop a non-invasive screening method for the risk loci.

METHODS

We genotyped 2 risk alleles on the MHC loci, HLA-DPA1 (rs3077) and HLA-DPB1 (rs9277535), and 1 risk allele near a non-MHC gene, FOXP1 (rs6789153) using high-resolution melting curve analysis. With minimal processing steps and time, salivary DNA was extracted with a modified protocol of a blood kit. We compared the genotyping fidelity between peripheral blood DNA and salivary DNA.

RESULTS

Both rs3077 and rs9277535, but not rs6789153, are significantly associated with CHB in Chinese population (p-value<0.001). High genotype concordance between different sources of genomic DNA was obtained.

CONCLUSIONS

Genotyping salivary DNA using our modified methods provides a non-invasive fast screening for host susceptibility loci. The transmission mechanism of hepatitis B can now be modified by adding genetic susceptibility to the traditional vertical transmission model of hepatitis B.

Evaluation of saliva specimens as an alternative sampling method to detect hepatitis B surface antigen

In this study, a modified enzyme immunoassay (EIA) was evaluated for the Hepatitis B surface antigen (HBsAg) among whole saliva and oral fluid samples. Specimens were collected from 115 individuals who gave serum and oral fluid using Salivette (Sarstedt, Nümbrecht, Germany) and whole saliva. Saliva specimens were tested following a modified ELISA, and the results were compared with paired serum specimens that were tested according to the supplier's instructions. Transport buffer for the oral fluids, sample volume for assay, incubation period of sample with conjugate as well as cut-off values were evaluated to optimize the assay. The highest sensitivity and specificity were obtained by increasing the incubation of sample and conjugate to 16  hr and using the area under the receiver operating characteristic curve to calculate cut-off values. HBsAg was detected in 40 oral fluids and 44 whole saliva samples out of 47 paired positive serum specimens and not detected in 64 oral fluids and 63 whole saliva samples out of 68 matched negative sera samples by the ELISA assay. There was excellent agreement between the results for the serum and saliva specimens kappa value (κ): 0.80 for oral fluid and κ: 0.87 for whole saliva and there was excellent reproducibility. Using an optimized protocol, the sensitivities of whole saliva and oral fluid were 93.6 and 85.1%, respectively, whereas specificities of whole saliva and oral fluid were 92.6 and 94.1%, respectively. Our data showed a significant promise for the use of whole saliva and oral fluid together with the modified commercial EIA for Hepatitis B virus infection surveillance.