Hepatitis C Virus	Epidemiology	Vertical Transmission	Tests
Management of Pregnant Women	Management of Infants born to HCV Positive Mothers	Other related Documents	References

Hepatitis C Virus

• Single-stranded negative sense RNA virus.
• Cytopathic virus, replicating in liver cells and spilling over into blood stream during active infection.
• Damage to liver leads to steatosis, fibrosis, cirrhosis and in some cases hepatocellular carcinoma.
• Major reason for liver transplantation world-wide.
• USA – 0.2% seroprevalence of HCV for children under 12 years of age.

Epidemiology

• Currently no tissue culture infectivity assay, so information on distribution of virus based largely on detection of viral RNA.
• Transmission still incompletely understood. Up to 40% of infected individuals may have no identifiable risk factors.
• >95% of infections thought to be parenteral, with injection of infectious blood the most at risk procedure eg injecting drug users, and (pre-transfusion service screening), haemophiliacs, transfusion recipients.
• In Western communities, < 5% of infections linked to sexual transmission or household exposure.
• Antibodies not protective against re-infection.
• Currently no vaccine available.

Vertical Transmission

• Infrequent (as opposed to vertical transmission of Hepatitis B in the pre-vaccine era).
• Rate approximately 6% in HCV viraemic, non-HIV infected mothers. May increase to ~ 15% in HIV positive mothers.
• Majority of infant infections probably acquired during exposure to infectious blood at delivery (infants not viraemic until several weeks post-delivery). However, there are no convincing studies at this time demonstrating that Caesarean section should be recommended.
• Transmission from breast milk has not been documented, although virus RNA can be found in breast milk. Currently there are no recommendations concerning breast feeding by HCV positive mothers. This should be discussed with the women but breast feeding is not contraindicated.

Tests

• Antibody to HCV. Indicates past infection, or passive acquisition of maternal antibody (infants).
• HCV RNA. Detects specific HCV genetic sequences by RT-PCV. Usually applied to blood (serum). If positive, indicates ongoing active infection.
• Currently there is no reliable HCV antigen test.

Management of Pregnant Women

• Offer testing to all pregnant women at risk of HCV (eg on the methadone programme or attending clinic for substance abuse).
• Ensure that the laboratory request is annotated " HCV screening in pregnancy."
• All antibody positive women must have HCV RNA tested.
• If positive, HIV testing must be offered also. (Note. This may become redundant with the introduction of widespread screening for HIV in pregnancy).

Management of Infants Born to HCV Positive Women

• Since essentially no infected infants have been found viraemic at birth, testing of cord blood is not necessary.

At 4-6 months:-

• Test for HCV RNA (HCV PCR), HCV antibody plus liver function tests.
  • Note: in many instances, maternal antibody will be detectable for >12 months.

• If HCV RNA positive, refer to Paediatric Gastroenterology Clinic.
• If HCV RNA negative and HCV antibody positive, repeat antibody test at 18 months to document clearance of antibody (and therefore absence of infection).
• If HCV RNA and HCV antibody negative, no further follow-up is required.

References