Shift in the buoyant density of hepatitis C virus particles in infants infected by mother-to-infant transmission

Hepatitis C in Pregnancy: A Unique Opportunity to Improve the Hepatitis C Cascade of Care

Hepatitis C has increasingly affected women of child-bearing age over the past few years as a result of the opioid epidemic. In this review, we discuss the effect of hepatitis C on pregnancy outcomes, effect of pregnancy on hepatitis C, as well as implications on management of hepatitis C during pregnancy.

Transmission of hepatitis C virus infection from asymptomatic mother to child in southern India

BACKGROUND

Little information is available on the mother-to-child transmission of hepatitis C virus (HCV) in India, and no interventions to decrease transmission rates have been identified. Hence, we performed a long-term prospective study in infants born to HCV-positive mothers, with the aim of evaluating vertical transmission of HCV and correlated risks factors.

METHODS

Three thousand one hundred and fifteen healthy asymptomatic pregnant women were included in the study. We used third-generation (Murex anti-HCV) ELISA and HCV RNA reverse transcription PCR (RT-PCR) for screening, and the commercial line probe assay (Inno-LiPA) and direct sequencing HCV genotyping assays were performed to confirm the transmitted HCV genotypes.

RESULTS

Of the total 3115 healthy asymptomatic pregnant women, 18 (0.6%) were positive for anti-HCV. Of the 18 anti-HCV-positive women, eight (44.4%) were positive for HCV RNA RT-PCR. HCV transmission was observed in two of the eight babies born to eight HCV RNA-positive mothers who were followed up for 12 months. HCV genotyping of the mother/child pairs revealed the persistent presence of mixed genotypes 1a and 4 throughout the follow-up period. None of the non-viremic (HCV RNA-negative) mothers transmitted HCV infection to their baby. In our study approximately 25% of vertical/perinatal transmission of HCV was observed among HCV RNA-positive antenatal women.

CONCLUSIONS

This study is of importance as it is the first report from India of a successful attempt to analyze the rate of vertical/perinatal transmission of HCV from infected mothers to their children by a prospective longitudinal follow-up study, and to characterize the pattern of genotype(s) of HCV present in the infected mother/baby pairs, so as to confirm the source of HCV acquired by the newborn babies.

Vertical transmission of hepatitis C virus in a hospital in southern Brazil

BACKGROUND: There still are controversies concerning the vertical transmission of hepatitis C virus. AIM: To evaluate the prevalence of antibodies against hepatitis C virus in pregnant women, as well as the rate of vertical transmission of this virus. PATIENTS AND METHODS: Between August 1998 and November 1999, 1,090 consecutive pregnant women were screened for anti-hepatitis C virus; positive results were confirmed by the polymerase chain reaction assay. Patient's viral load was evaluated by the branched deoxyribonucleic acid assay. Hepatitis C virus genotype was identified by direct sequencing of the polymerase chain reaction amplification products. The same tests were performed in the children born from infected mothers at the 1st and 6th month of life. RESULTS: Of the 1,090 mothers surveyed, 29 were positive for anti-hepatitis C virus (prevalence of 2.66%). Twenty-five patients presented with hepatitis C virus RNA, with a median hepatitis C virus viral load of 3.132 ± 5.891 MEq/mL. Twenty-two patients (six human immunodeficiency virus-coinfected) were followed and gave birth to 23 children; 18 of them had blood samples tested at the 1st month of life, and 22, at the 6th month. Vertical transmission rate was 5.56%; it affected a girl who had hepatitis C virus RNA detectable only in the 1st month sample (41.570 MEq/mL). The mother who transmitted hepatitis C virus was coinfected with human immunodeficiency virus and presented with an hepatitis C virus viral load of 3.765 MEq/mL, with 100% homology with her daughter's hepatitis C virus genotype. CONCLUSION: These results suggest that the prevalence of hepatitis C virus infection in pregnant women should not be neglected, and early diagnosis of vertical transmission and the follow up of infected children should be emphasized.

Maternal-infant transmission of hepatitis C virus infection

Mother-to-infant transmission of hepatitis C virus (HCV) is comparatively uncommon. The prevalence of antibody to HCV (anti-HCV) in pregnant women is 0.1% to 2.4%, although in some endemic areas it is much higher. The proportion of women with anti-HCV who have active infection with viremia is 60% to 70%. Transmission of HCV occurs only when serum HCV RNA is detectable and may be related to higher levels (above 10(6) copies per mL). The rate of mother-to-infant transmission is 4% to 7% per pregnancy in women with HCV viremia. Co-infection with human immunodeficiency virus (HIV) increases the rate of transmission 4 to 5 fold. The actual time and mode of transmission are not known. Elective Cesarean section is not recommended for women with chronic HCV infection alone. The role of treatment to prevent transmission is limited by the fetal toxicity of currently available medications for hepatitis C. Breast feeding poses no important risk of HCV transmission if nipples are not traumatized and maternal hepatitis C is quiescent. Pregnant women at high risk for HCV infection should be screened for anti-HCV, and HCV RNA testing should be performed if anti-HCV is positive. Infants of women with hepatitis C should be tested for HCV RNA on two occasions, between the ages of 2 and 6 months and again at 18 to 24 months, along with serum anti-HCV. The natural history of mother-to-infant hepatitis C remains uncertain, especially the course in the first year of life when some infants appear to have spontaneous resolution.

Maternal-infant transmission of hepatitis C virus infection

Mother-to-infant transmission of hepatitis C virus (HCV) is comparatively uncommon. The prevalence of antibody to HCV (anti-HCV) in pregnant women is 0.1% to 2.4%, although in some endemic areas it is much higher. The proportion of women with anti-HCV who have active infection with viremia is 60% to 70%. Transmission of HCV occurs only when serum HCV RNA is detectable and may be related to higher levels (above 10(6) copies per mL). The rate of mother-to-infant transmission is 4% to 7% per pregnancy in women with HCV viremia. Co-infection with human immunodeficiency virus (HIV) increases the rate of transmission 4 to 5 fold. The actual time and mode of transmission are not known. Elective Cesarean section is not recommended for women with chronic HCV infection alone. The role of treatment to prevent transmission is limited by the fetal toxicity of currently available medications for hepatitis C. Breast feeding poses no important risk of HCV transmission if nipples are not traumatized and maternal hepatitis C is quiescent. Pregnant women at high risk for HCV infection should be screened for anti-HCV, and HCV RNA testing should be performed if anti-HCV is positive. Infants of women with hepatitis C should be tested for HCV RNA on two occasions, between the ages of 2 and 6 months and again at 18 to 24 months, along with serum anti-HCV. The natural history of mother-to-infant hepatitis C remains uncertain, especially the course in the first year of life when some infants appear to have spontaneous resolution.

Evolution in the hypervariable region of hepatitis C virus in infants after vertical transmission

To elucidate the clonal evolution of hepatitis C virus (HCV) during mother-to-infant transmission, we prospectively analyzed HCV clones of the hypervariable region in four HCV RNA-positive infants and compared them with those of the mother. Cord blood samples from three of the four infants were positive for the HCV RNA (< or =10(3) copies/mL), and all of the four infants had the HCV RNA titer of >10(6) copies/mL within 2 mo after birth. The hypervariable region clones detected in the infants were closely related to those in the respective mothers. The results suggest the perinatal transmission of HCV. The hypervariable region clones transmitted to infants were not a single selected clone or minor clones in the mother. None of the clones specific to the low-density fraction in the mother was transmitted to the infants. Moreover, the proportion of HCV in the low-density fraction was minimal in the first few months of life, but increased several months after birth in association with the elevation of alanine aminotransferase. These results suggest that the increase of HCV in the low-density fraction reflect the evolution of immune response in infants. We also demonstrated that the emergence of quasispecies in infants precedes the infantile antibody response.