Is hepatitis B virus transmitted via the male germ line? A seroepidemiological study in fetuses

Paternal Preconception Hepatitis B Virus Infection and Risk of Congenital Heart Disease in Offspring

Importance

Previous evidence suggests that maternal hepatitis B virus (HBV) infection during prepregnancy or pregnancy is associated with congenital heart diseases (CHDs) in offspring. However, the association of paternal HBV infection with CHDs is not well examined.

Objective

To explore the association of paternal preconception HBV infection with CHDs in offspring.

Design, Setting, and Participants

This retrospective cohort study used propensity score matching of data from the Chinese National Free Preconception Checkup Project (NFPCP) from January 1, 2010, to December 31, 2018. Male participants whose wives were aged 20 to 49 years, were uninfected with HBV, and successfully conceived within 1 year after prepregnancy examination were enrolled. Data were analyzed from March 2023 to February 2024.

Exposures

The primary exposure was paternal preconception HBV infection status, including uninfected, previous infection (both serum hepatitis B surface antigen and hepatitis B envelope antigen negative), and new infection (serum hepatitis B surface antigen positive). Maternal HBV immune status was further classified as immune or susceptible.

Main Outcomes and Measures

The main outcome was CHDs, which were collected from the birth defect registration card of the NFPCP. Logistic regression with robust error variances was used to estimate the association between paternal preconception HBV infection and CHDs in offspring.

Results

A total of 6 675 540 couples participated in the NFPCP service. After matching husbands with and without preconception HBV infection in a 1:4 ratio, 3 047 924 couples (median age of husbands, 27 years [IQR, 25-30 years]) were included in this study. Of these couples, 0.025% had offspring with CHDs. Previous paternal HBV infection was independently associated with CHDs in offspring (adjusted relative risk [ARR], 1.40; 95% CI, 1.11-1.76) compared with no infection. Similar results were obtained in subgroup analyses according to maternal HBV immune status. Compared with couples with uninfected husbands and susceptible wives, the risk of CHDs in offspring among couples with previously HBV-infected husbands was similar in couples with wives with susceptible immune status (ARR, 1.49; 95% CI, 1.10-2.03) and in those with wives with immunity (ARR, 1.49; 95%CI, 1.07-2.09). A significantly higher CHD risk in offspring was found among couples with newly infected husbands and immune wives (ARR, 1.38; 95% CI, 1.05-1.82), but there was no difference in risk among those with newly infected husbands and susceptible wives (ARR, 0.99; 95% CI, 0.72-1.36). No interactions were found between maternal immune status and paternal HBV infection.

Conclusions and Relevance

In this cohort study using propensity score matching, previous paternal preconception HBV infection was associated with CHD risk in offspring. The findings suggest that personalized reproductive guidance regarding HBV screening and staying free of HBV infection should be provided for both wives and husbands.

Differential methylation patterns in paternally imprinted gene promoter regions in sperm from hepatitis B virus infected individuals

BACKGROUND

Hepatitis B virus (HBV) infection poses a substantial threat to human health, impacting not only infected individuals but also potentially exerting adverse effects on the health of their offspring. The underlying mechanisms driving this phenomenon remain elusive. This study aims to shed light on this issue by examining alterations in paternally imprinted genes within sperm.

METHODS

A cohort of 35 individuals with normal semen analysis, comprising 17 hepatitis B surface antigen (HBsAg)-positive and 18 negative individuals, was recruited. Based on the previous research and the Online Mendelian Inheritance in Man database (OMIM, https://www.omim.org/ ), targeted promoter methylation sequencing was employed to investigate 28 paternally imprinted genes associated with various diseases.

RESULTS

Bioinformatic analyses revealed 42 differentially methylated sites across 29 CpG islands within 19 genes and four differentially methylated CpG islands within four genes. At the gene level, an increase in methylation of DNMT1 and a decrease in methylation of CUL7, PRKAG2, and TP53 were observed. DNA methylation haplotype analysis identified 51 differentially methylated haplotypes within 36 CpG islands across 22 genes.

CONCLUSIONS

This is the first study to explore the effects of HBV infection on sperm DNA methylation and the potential underlying mechanisms of intergenerational influence of paternal HBV infection.

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.

Pharmacological approaches to prevent vertical transmission of HIV and HBV

INTRODUCTION

Mother-to-child transmission (MTCT) is mainly responsible for the global pediatric HIV and HBV epidemic. Vertical transmission can be prevented and reduced through a series of interventions at the primary healthcare level, including extensive screening of pregnant women, administration of antivirals or immune-based treatments, counselling on type of delivery and breastfeeding.

AREAS COVERED

In this narrative review, approved therapeutic options for the treatment of pregnant women living with HIV or HBV are discussed with special focus on efficacy and safety profiles of each agent or drug class examined. The search was performed using Medline (via PubMed), Web of Science, and Google Scholar to identify studies assessing vertical transmission of both HIV and HBV.

EXPERT OPINION

Elimination of MTCT of both infections is firmly endorsed by major global commitments and the integration of tailored preventive interventions into maternal and newborn health services is of strategical importance to achieve this critical target. However, further research centered on antiviral-based and immunization trials among pregnant women is urgently needed to mitigate the risk of maternal and neonatal adverse outcomes, effectively prevent transmission to the offspring and finally eliminate the pediatric HIV and HBV epidemic, one of the key global health challenges of our time.

Managing and preventing blood-borne viral infection transmission in assisted reproduction: a Canadian Fertility and Andrology Society clinical practice guideline

Fertility care providers have an obligation to provide safe and effective care to patients. When a user of assisted reproductive technology (ART) is living with a blood-borne viral infection (BBVI: HIV, hepatitis C or hepatitis B), physicians and ART laboratory personnel need to know the requirements for providing quality care. Recent developments in the treatment of BBVI and understanding of transmission have changed these requirements. This guideline from the Canadian Fertility and Andrology Society (CFAS) provides comprehensive, evidence-based guidelines for reducing horizontal transmission and cross-contamination in the ART setting.

Reproductive considerations in the setting of chronic viral illness

Special considerations must be taken when patients with human immunodeficiency virus (HIV), hepatitis B, or hepatitis C desire to become pregnant. Patients with chronic viral illnesses desire to have children at rates similar to the general population, and options are available to decrease both vertical transmission and viral transmission between partners. Preconception counseling or consultation with fertility specialists is imperative in patients with HIV, hepatitis B, and hepatitis C so that reproductive goals can be addressed and optimized. In couples in which one partner has HIV, the use of highly active antiretroviral therapy or preexposure prophylaxis can significantly reduce the risk of transmission between serodiscordant partners. The use of density gradient sperm-washing techniques and intrauterine insemination or in vitro fertilization results in an apparent lack of transmission of HIV between partners when the male partner is HIV-positive. Vertical transmission of HIV from mother to child can be reduced by use of highly active antiretroviral therapy regimens throughout pregnancy or by cesarean delivery in the setting of high maternal viral load. Transmission of hepatitis B between partners can be eliminated by vaccinating the uninfected partner. Vertical transmission from a hepatitis B-infected mother to a child can be reduced by vaccinating neonates with the standard hepatitis B vaccine series as well as hepatitis B immune globulin. Recent data have shown the antiviral medication tenofovir to be an effective way to reduce vertical transmission in the setting of high maternal viral load or the presence of hepatitis B e antigen. There are multiple antiviral medications available to treat chronic hepatitis C, although access to these medications often is limited by cost. Similar to HIV-positive patients, in settings in which the male partner is infected with hepatitis C, density gradient sperm washing can be used before intrauterine insemination or in vitro fertilization to reduce transmission of hepatitis C between partners. No safe and effective method exists to reduce vertical transmission of hepatitis C once a woman becomes pregnant, highlighting the importance of treatment of hepatitis C before pregnancy.

Mechanisms and Prevention of Vertical Transmission in Chronic Viral Hepatitis

Vertical transmission (VT) is the primary route of transmission of viral hepatitis in children. The rate of VT ranges from 1-28% with hepatitis B virus (HBV) and 3-15% with hepatitis C virus (HCV). VT for both viruses can occur during the intrauterine or peripartum period. VT of HBV primarily occurs by intrauterine transmission (IUT). Hepatitis B surface antigen is unable to cross the placenta and, therefore, relies on processes like transplacental leakage, placental infection, cellular transmission by peripheral blood mononuclear cells, and germline transmission. HCV can also infect the fetus by IUT. Both viruses also have the potential for transmission during delivery, when there is increase chance of maternal-fetal blood exposure. HBV and HCV share some common risk factors for VT, including maternal viral load, human immunodeficiency virus co-infection and neonatal sex. Prevention of VT differs greatly between HBV and HCV. There are several alternatives for prevention of HBV VT, including antiviral medications during the third trimester of pregnancy and HBV vaccine, as well as hepatitis B immunoglobulin administration to infants post-partum. In contrast, there are no preventative interventions available for HCV. Despite these differences, the key to prevention with both viruses is screening women prior to and during pregnancy.

Efficacy and safety of nucleoside analogs on blocking father-to-infant vertical transmission of hepatitis B virus

The aim of the present study was to observe the efficacy and safety of nucleoside analogs in inhibiting father-to-infant vertical transmission of hepatitis B virus (HBV). Nucleoside analogs compete with HBV DNA polymerase substrate to inhibit DNA polymerase, thus preventing the replication of HBV DNA. A case group and control group were recruited for the study. Between March 2006 and March 2012 at the Liver Disease Center of Qinhuangdao Third Hospital, a total of 201 couples were recruited for the case group. In each case, the father tested positive the following HBV markers: Hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), antibodies against the hepatitis B core antigen (anti-HBc) and HBV DNA. In total, 189 male patients presented with abnormal liver function (94.0%; 189/201). Prior to pregnancy, all the males in the case group were required to test negative for HBV DNA and exhibit normal liver function, while the females were required to test positive for antibodies against HBsAg (anti-HBs). In total, 188 couples comprised the control group. The couples were recruited between March 2006 and March 2012 in the Prenatal Clinic of Qinhuangdao Women's and Children's Hospital. The fathers tested positive for HBsAg, HBeAg, anti-HBc and HBV DNA. With regard to the females, HBsAg tests were all negative and anti-HBs tests were positive. In the case group, there were no HBsAg-positive or HBV DNA-positive newborns, while anti-HBs tests were all positive; thus, the father-to-infant HBV vertical transmission was successfully inhibited. In the control group, 147/188 newborns tested positive for anti-HBs at birth, accounting for 78.2%. In addition, 28 newborns were positive for HBV DNA (14.9%), and 19 newborns tested positive for HBsAg (10.1%). Statistically significant differences were observed between the two groups with regard to these parameters. However, no statistically significant differences in gestational age, birth weight, birth height, 1- and 8-min Apgar scores, presence of jaundice, other internal and surgical diseases, delivery mode and other birth information were observed when comparing the case group with the control group. Furthermore, there were no fetal malformations or stillbirths in the two groups. In the HBV DNA-positive fathers prior to pregnancy, antiretroviral therapy resulted in a reduced virus load. Therefore, blocking father-to-infant HBV vertical transmission maximally was important. The use of antiviral nucleoside analogs prior to pregnancy was shown to be safe. When the benefits outweighed the risks, the fathers who wanted to have a child continued to use antiviral therapy. However, the sample size of the present study was small, and an increased number of cases and longer follow-up times are required. In addition, the use of nucleoside analogs requires further in-depth assessment from the point of view of prenatal and postnatal care.

[Reproductive options for people living with HIV: 2013 guidelines from the French expert working group]

The desire for children is a legitimate aspiration that should be part of multidisciplinary care for all men, women or couples living with HIV. The use of effective antiretroviral therapy has revolutionized the prevention of sexual, as well as mother-to-child HIV transmission. When the HIV plasma viral load is undetectable on long-term antiretroviral therapy, the risk of mother-to-child transmission is <1% and the risk of heterosexual HIV transmission without condom use in a stable relationship is very low (estimated at less than 1/10,000) in the absence of inflammation of the genital tract. In a man with a long-term undetectable viral load, viral shedding in semen is uncommon, but may occur persistently or intermittently. The same appears true of viral shedding in the vaginal tract of women. Reproductive options are: natural conception, self-insemination when the woman is HIV-infected, assisted reproduction. Natural conception is now considered to be an acceptable option when the conditions are met, after exploring four aspects: (1) virological (viral load undetectable sustained for at least 6 months on therapy), (2) genital (absence of genital infections or lesions), (3) fertility (after appropriate evaluation) and (4) detecting the ovulation period to limit intercourse without condoms. Assisted reproduction has two objectives in the context of HIV, to allow the couple to conceive without abandoning condom use and/or to treat infertility.