Vertical transmission of hepatitis C: towards universal antenatal screening in the era of new direct acting antivirals (DAAs)? Short review and analysis of the situation in Switzerland

Overall Vertical Transmission of Hepatitis C Virus, Transmission Net of Clearance, and Timing of Transmission

BACKGROUND

It is widely accepted that the risk of hepatitis C virus (HCV) vertical transmission (VT) is 5%-6% in monoinfected women, and that 25%-40% of HCV infection clears spontaneously within 5 years. However, there is no consensus on how VT rates should be estimated, and there is a lack of information on VT rates "net" of clearance.

METHODS

We reanalyzed data on 1749 children in 3 prospective cohorts to obtain coherent estimates of overall VT rate and VT rates net of clearance at different ages. Clearance rates were used to impute the proportion of uninfected children who had been infected and then cleared before testing negative. The proportion of transmission early in utero, late in utero, and at delivery was estimated from data on the proportion of HCV RNA positive within 3 days of birth, and differences between elective cesarean and nonelective cesarean deliveries.

RESULTS

Overall VT rates were 7.2% (95% credible interval [CrI], 5.6%-8.9%) in mothers who were human immunodeficiency virus (HIV) negative and 12.1% (95% CrI, 8.6%-16.8%) in HIV-coinfected women. The corresponding rates net of clearance at 5 years were 2.4% (95% CrI, 1.1%-4.1%), and 4.1% (95% CrI, 1.7%-7.3%). We estimated that 24.8% (95% CrI, 12.1%-40.8%) of infections occur early in utero, 66.0% (95% CrI, 42.5%-83.3%) later in utero, and 9.3% (95% CrI, 0.5%-30.6%) during delivery.

CONCLUSIONS

Overall VT rates are about 24% higher than previously assumed, but the risk of infection persisting beyond age 5 years is about 38% lower. The results can inform design of trials of interventions to prevent or treat pediatric HCV infection, and strategies to manage children exposed in utero.

Viral hepatitis C during pregnancy: prevalence, impact on perinatal outcomes, patient management tactics (literature review)

The article presents modern ideas about the impact of viral hepatitis C on the course of pregnancy, the severity of maternal disease associated with it: methods of delivery and possible vertical transmission. Epidemiological data on the prevalence in the world and the Russian Federation, risk factors for perinatal HCV transmission, and the course of pregnancy in women infected with HCV are shown. The search for the necessary literary sources was carried out in the databases Scopus, PubMed, MedLine, The Cochrane Library, RSCI.

Knowledge of Hepatitis C virus vertical transmission and subsequent pregnancy outcome in virus-positive female blood donors

Introduction

Hepatitis C virus (HCV) can be vertically transmitted from mother to fetus. We evaluated knowledge about HCV vertical transmission in female blood donors who became pregnant following detection of HCV in their donated blood.

Methods

This was a retrospective descriptive study of females seen at a single blood bank in Sao Paulo, Brazil who were diagnosed with HCV infection in their donated blood. HCV-infected donors who subsequently became pregnant were invited to participate through letters or phone calls. Individuals who agreed to participate were interviewed by questionnaire to evaluate their knowledge on HCV vertical transmission.

Results

Among 282 HCV-positive female blood donors, 69 reported becoming pregnant after their HCV diagnosis in donated blood. While 24 of these women were successful treated for their infection prior to becoming pregnant, 45 (65.2%) were at risk for vertical HCV transmission either because they had never been treated for HCV, were pregnant before treatment or became pregnant after unsuccessful treatment. Of the 59 women who responded to the question of whether they were informed about the risk of HCV vertical transmission, 58 (98.3%) reported never receiving this information either after obtaining their blood donation results or during their pregnancy.

Conclusion

The lack of knowledge of HCV-infected women on the possibility for mother-to-child transmission of this virus highlights the critical need to improve communication about pregnancy-related risks between health professionals and HCV-infected women of childbearing age.

Prevalence of HIV, Syphilis, Hepatitis B and C in pregnant women at a maternity hospital in Salvador

Abstract Objectives: to calculate the prevalence and rate per 1,000 live births of sexually transmitted infections (STI) in pregnant women at a public maternity hospital in Salvador. Methods: this descriptive, cross-sectional study retrospectively collected data from compulsory notifications and medical records of pregnant women with STI seen at a maternity hospital in northeastern Brazil between 2014 and 2017 (n = 520). Prevalence and rate per 1,000 live births were estimated for hepatitis B, hepatitis C, HIV, and syphilis. Associations between STI and other clinical and sociodemographic variables were investigated. Results: most pregnant women were born and resided in Salvador, presented a mean age of 26.4 years, self-reported mixed-race and had unplanned pregnancies. Prevalence and rates per 1,000 live births were, respectively: 0.26% and 3.39 for hepatitis B, 0.06% and 0.79 for hepatitis C, 0.47% and 6.23 for HIV, and 2.46% and 32.2 for syphilis. Conclusion: higher prevalence and rates of infection per 1,000 live births were seen at the maternity hospital in northeastern Brazil compared to official data provided by the Brazilian government, notably with regard to HIV and syphilis. The appropriate epidemiological notification of STI, especially in pregnant women, enables the elaboration of effective preventive strategies incorporating specific sociodemographic and clinical characteristics.

Changing epidemiology, implications, and recommendations for hepatitis C in women of childbearing age and during pregnancy

Despite the remarkable advances in HCV treatment brought about by the advent of direct-acting antivirals, HCV remains a global public health concern. One particular concern relates to the rising prevalence of HCV in women of childbearing age. Active HCV during pregnancy is associated with cholestasis of pregnancy as well as the risk of mother-to-child transmission. Guidelines are increasingly recommending universal screening during pregnancy, while the treatment of HCV during pregnancy is an area of ongoing research.

Hepatitis C in 2020: A North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition Position Paper

In 1989, a collaboration between the Centers for Disease Control (CDC) and a California biotechnology company identified the hepatitis C virus (HCV, formerly known as non-A, non-B hepatitis virus) as the causative agent in the epidemic of silent posttransfusion hepatitis resulting in cirrhosis. We now know that, the HCV genome is a 9.6 kb positive, single-stranded RNA. A single open reading frame encodes a 3011 amino acid residue polyprotein that undergoes proteolysis to yield 10 individual gene products, consisting of 3 structural proteins (core and envelope glycoproteins E1 and E2) and 7 nonstructural (NS) proteins (p7, NS2, NS3, NS4A, NS4B, NS5A, and NS5B), which participate in posttranslational proteolytic processing and replication of HCV genetic material. Less than 25 years later, a new class of medications, known as direct-acting antivirals (DAAs) which target these proteins, were introduced to treat HCV infection. These highly effective antiviral agents are now approved for use in children as young as 3 years of age and have demonstrated sustained virologic responses exceeding 90% in most genotypes. Although tremendous scientific progress has been made, the incidence of acute HCV infections has increased by 4-fold since 2005, compounded in the last decade by a surge in opioid and intravenous drug use. Unfortunately, awareness of this deadly hepatotropic virus among members of the lay public remains limited. Patient education, advocacy, and counseling must, therefore, complement the availability of curative treatments against HCV infection if this virus is to be eradicated.

Anti-HCV prevalence and risk factor-based screening for hepatitis C in pregnant women and their partners in Sweden

BACKGROUND

The hepatitis C virus (HCV) prevalence in Sweden is estimated to be <0.5%, but unclear in pregnant women. The dominating route of transmission is drug use (DU), blood transfusions constituted a risk before 1992. The aim was to examine the anti-HCV prevalence and risk factors for HCV among pregnant women and their partners to evaluate screening strategies.

METHODS

Pregnant women and partners in Örebro County and in southern Stockholm were offered HCV-screening when visiting an antenatal clinic in 2013-2016, and completed a questionnaire concerning the country of birth, knowledge of HCV-status and HCV risk factors.

RESULTS

In Örebro 2,827 pregnant women and 707 partners, and in Stockholm 1,281 pregnant women and 320 partners participated. Anti-HCV was positive in 34 (0.7%) (25 pregnant women) and the associated risk factors were DU (n = 27), partner with HCV (n = 24) and not born in Sweden (n = 8). HCV RNA was positive in 23 (0.4%), 4 previously unknown and 10 who had been lost to follow-up. The most effective risk factor-based screening model for pregnant women included DU, blood transfusions, born in high prevalence country, partner with HCV, resulting in 538 (13%) pregnant women tested with 96% sensitivity, 87% specificity.

CONCLUSIONS

In this study of expecting parents in two Swedish regions, the anti-HCV prevalence was 0.7% and 0.4% were viraemic, of which about 60% were previously unknown or lost to follow-up. Awaiting more studies, including cost-benefit analysis evaluating universal screening, we recommend this improved risk factor-based screening model to identify HCV-infected individuals who need follow-up and therapy.

Perinatal HCV Transmission Rate in HIV/HCV Coinfected women with access to ART in Madrid, Spain

BACKGROUND

Maternal HIV coinfection is a key factor for mother-to-child transmission (MTCT) of HCV. However, data about HCV MTCT in HIV/HCV-coinfected pregnant women on combined antiretroviral treatment (ART) are scarce. This study assessed the HCV MTCT rate in the Madrid Cohort of HIV-infected women.

METHODS

Retrospective study within the Madrid Cohort of HIV-infected pregnant women (2000-2012). Epidemiological, clinical and treatment related variables were analysed for the mother and infant pairs. HCV MTCT rate was determined.

RESULTS

Three hundred thirty-nine HIV/HCV-coinfected women and their exposed infants were recorded. A total of 227 (67%) paired mother-children had available data of HCV follow-up and were included for the analysis. Sixteen children (rate 7.0%, 95%CI 3.7-10.4%) were HCV infected by 18 months of age, none of them coinfected with HIV. HIV/HCV-coinfected pregnant women were mostly of Spanish origin with a background of previous injection drug use. HCV-genotype 1 was predominant. The characteristics of mothers that transmitted HCV were similar to those that did not transmit HCV with respect to sociodemographic and clinical features. A high rate (50%) of preterm deliveries was observed. Infants infected with HCV were similar at birth in weight, length and head circumference than those uninfected.

CONCLUSION

MTCT rates of HCV among HIV/HCV-coinfected women on ART within the Madrid cohort were lower than previously described. However, rates are still significant and strategies to eliminate any HCV transmission from mother to child are needed.

Review article: direct-acting antivirals for the treatment of HCV during pregnancy and lactation - implications for maternal dosing, foetal exposure, and safety for mother and child

BACKGROUND

With the global efforts to eradicate hepatitis C virus (HCV), treatment during pregnancy is becoming a priority for research as this, and maternal cure should reduce vertical transmission. However, as information on the efficacy and safety of direct-acting antivirals (DAAs) in pregnancy is generally lacking, treatment of HCV infection during pregnancy is not currently recommended.

AIM

To provide an overview of current knowledge regarding maternal exposure, placental handling and safety of DAAs during pregnancy and lactation METHODS: A literature search was performed focusing on the effect of pregnancy on maternal exposure to DAAs, the placental handling of DAAs, the safety of DAAs for mother and child during pregnancy and the safety of DAAs during lactation.

RESULTS

Exposure to all DAAs studied is likely to be altered during pregnancy, mostly related to pregnancy-induced effects on drug absorption and metabolism. Although animal studies show that most DAAs are reported to cross the placenta and transfer into breast milk, most DAA combinations show a favourable safety profile. Because of the rapid viral decline after treatment initiation, and to avoid the critical period of organogenesis, treatment may be started at the end of the second trimester or early third trimester.

CONCLUSIONS

Treatment of HCV infection during pregnancy is realistic, as DAAs are highly effective and treatment duration is relatively short. There is an urgent need to study DAAs during pregnancy and lactation to contribute to the goal of HCV elimination.

Risk-Based Prenatal Hepatitis C Testing Practices and Results, Alaska 2013-2016

Hepatitis C virus (HCV) infection in pregnant women is of concern as it presents a health threat not only to the mother, but also to her infant. A retrospective analysis was performed to evaluate HCV testing and exposure in women who delivered infants between 2013 and 2016 at a referral hospital in Alaska. Multiple risk behaviors were evaluated, including drug dependency or abuse (drug abuse), tobacco use, alcohol dependency or abuse, and late presentation to prenatal care. Of the 2856 women who delivered between 2013 and 2016, 470 (16.5%) were tested for HCV during pregnancy and 1356 (47.5%) were tested at any time prior to delivery (including pregnancy); 62 (2.2%) were positive for HCV antibodies. Of the 162 women with a documented history of drug abuse, 95 (58.6%) were tested for HCV during pregnancy and 143 (88.3%) were tested at any time prior to delivery (including pregnancy); 30 (18.5%) were positive for HCV antibodies. Forty-nine women (34%) with a documented history of drug abuse who were not previously known to be HCV positive were not tested for HCV during their pregnancy. In conclusion, approximately 2% of pregnant women in the study population were known to have been exposed to HCV by the time of their delivery. One-third of women with documented drug abuse did not have an HCV test during pregnancy, revealing gaps in HCV testing of pregnant women. Further studies are needed to understand the full costs and benefits of risk-based screening versus universal screening in this and other populations.

Hepatitis C in Pregnancy in the Era of Direct-acting Antiviral Treatment: Potential Benefits of Universal Screening and Antepartum Therapy

Hepatitis C in pregnancy is on the rise, and new direct-acting antiviral agents are available that cure the disease. Published recommendations need to be reviewed and clinically evaluated for the care of pregnant women who are at risk for or have chronic hepatitis C. Available evidence and some of the medical and ethical reasons to consider universal screening and antepartum therapy for hepatitis C during pregnancy are presented. Universal screening and proactive treatment during pregnancy is on the horizon, and these measures should be quickly evaluated for safety and implemented if appropriate.

Perinatal Transmission of Hepatitis C Virus: Defining the Cascade of Care

OBJECTIVES

The US National Viral Hepatitis Action Plan calls for major efforts to expand hepatitis C virus (HCV) diagnosis and treatment; prenatal care settings are potential venues for expanding HCV testing. We aimed to characterize the HCV diagnostic cascade for women and infants and investigate factors associated with linkage and follow-up.

STUDY DESIGN

We used electronic health records for a 10-year cohort of 879 women with opioid use disorder from an obstetric clinic serving women with substance use disorders.

RESULTS

Altogether, 744 women (85%) were screened for HCV; 510 (68%) were seropositive, of whom 369 (72%) had nucleic acid testing performed and of these 261 (71%) were viremic. Of 404 infants born to HCV-seropositive women, 273 (68%) were tested at least once for HCV, 180 (45%) completed the American Academy of Pediatrics-recommended perinatal HCV screening, and 5 (2.8%) were diagnosed with HCV infection and linked to care. More recent delivery date (2014-2015) was associated with maternal linkage to care (aOR, 2.5; 95% CI, 1.4-4.7). Maternal coinfection with HIV (aOR, 9.0; 95% CI, 1.1-72.8) and methadone maintenance therapy, compared with buprenorphine (aOR, 1.5; 95% CI, 0.9-2.5), were associated with higher rates of infant HCV testing.

CONCLUSIONS

HCV prevalence among pregnant women with opioid use is high and infant HCV screening is imperfect. Programmatic changes to improve both mother and infant follow-up may help to bridge identified gaps in the cascade to cure.

Sexually acquired acute hepatitis C infection diagnosed during pregnancy: a case report of successful postpartum treatment

BACKGROUND

Infection with the hepatitis C virus (HCV) during pregnancy has emerged as an increasingly recognized and prevalent condition among women of reproductive age in the United States. While screening recommendations exist for pregnant women at high risk of HCV infection, pregnant women with HCV are often under-screened, not diagnosed, or do not receive adequate follow-up, thereby increasing the risk of suboptimal maternal and infant outcomes (including in future pregnancies).

CASE

A pregnant woman living with HIV presented with intrahepatic cholestasis of pregnancy. She had tested negative for HCV earlier in pregnancy as part of routine screening recommended for women living with HIV. She was found to have sexually acquired a new HCV infection from her partner during pregnancy. She successfully completed treatment postpartum.

CONCLUSION

With the rise in HCV infection among pregnant patients, physicians should be diligent in assessing pregnant women and their partners for HCV risk factors, testing for HCV when risk is identified, and arranging follow-up testing and treatment for HCV-positive mothers and their infants.

Hepatitis C in Pregnancy: Review of Current Knowledge and Updated Recommendations for Management

Importance

An estimated 1% to 2.5% of pregnant women in the United States are infected with hepatitis C virus (HCV), which carries approximately a 6% risk of mother-to-infant transmission.

Objectives

The aims of this article are to review the current evidence on HCV in pregnancy and to provide updated recommendations for management.

Evidence Acquisition

Original research articles, review articles, and guidelines on HCV in general and specifically in pregnancy were reviewed, as were drug safety profiles from the Food and Drug Administration.

Results

Pregnancy appears to have a beneficial effect on the course of maternal chronic HCV infection. However, it is associated with an increased risk of adverse fetal outcomes, including fetal growth restriction and low birth weight, and can be transmitted to the infant in utero or during the peripartum period. No perinatal intervention has been shown to reduce the risk of vertical transmission, but some may increase this risk. To date, no treatment regimens for HCV have been approved for use in pregnancy, but the new ribavirin-free, direct-acting antiviral regimens are being used with high efficacy outside pregnancy.

Conclusions and Relevance

Hepatitis C virus infection in pregnancy generally does not adversely affect maternal well-being but is associated with adverse effects on the fetus because of pregnancy complications and vertical transmission. There are currently no approved treatment regimens for HCV in pregnancy; this should be an active area of research in obstetrics.

Hepatitis C in pregnancy: screening, treatment, and management

In the United States, 1-2.5% of pregnant women are infected with hepatitis C virus, which carries an approximately 5% risk of transmission from mother to infant. Hepatitis C virus can be transmitted to the infant in utero or during the peripartum period, and infection during pregnancy is associated with increased risk of adverse fetal outcomes, including fetal growth restriction and low birthweight. The purpose of this document is to discuss the current evidence regarding hepatitis C virus in pregnancy and to provide recommendations on screening, treatment, and management of this disease during pregnancy. The following are Society for Maternal-Fetal Medicine recommendations: (1) We recommend that obstetric care providers screen women who are at increased risk for hepatitis C infection by testing for anti-hepatitis C virus antibodies at their first prenatal visit. If initial results are negative, hepatitis C screening should be repeated later in pregnancy in women with persistent or new risk factors for hepatitis C infection (eg, new or ongoing use of injected or intranasal illicit drugs) (GRADE 1B). (2) We recommend that obstetric care providers screen hepatitis C virus-positive pregnant women for other sexually transmitted diseases, including HIV, syphilis, gonorrhea, chlamydia, and hepatitis B virus (GRADE 1B). (3) We suggest that patients with hepatitis C virus, including pregnant women, be counseled to abstain from alcohol (Best Practice). (4) We recommend that direct-acting antiviral regimens only be used in the setting of a clinical trial or that antiviral treatment be deferred to the postpartum period as direct-acting antiviral regimens are not currently approved for use in pregnancy (GRADE 1C). (5) We suggest that if invasive prenatal diagnostic testing is requested, women be counseled that data on the risk of vertical transmission are reassuring but limited; amniocentesis is recommended over chorionic villus sampling given the lack of data on the latter (GRADE 2C). (6) We recommend against cesarean delivery solely for the indication of hepatitis C virus (GRADE 1B). (7) We recommend that obstetric care providers avoid internal fetal monitoring, prolonged rupture of membranes, and episiotomy in managing labor in hepatitis C virus-positive women (GRADE 1B). (8) We recommend that providers not discourage breast-feeding based on a positive hepatitis C virus infection status (GRADE 1A).

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.