Implementing universal testing for hepatitis C during
pregnancy improved case detection 7.5-fold compared to the previous regime of
risk-based screening, a research group from the University of Pittsburgh
reported last week at the 2022 Conference on Retroviruses and Opportunistic Infections (CROI).
Hepatitis C prevalence among pregnant women in western
Pennsylvania doubled between 2006 and 2016, from approximately 1% to over 2%. Increased
prevalence of hepatitis C among pregnant women in Pennsylvania is a consequence
of the opioid epidemic, said Dr Catherine Chappell of the University of
Pittsburgh.
Screening for hepatitis C in pregnancy can enable early
diagnosis before progression to cirrhosis and also prevent transmission of
hepatitis C to the infant (the vertical transmission rate of hepatitis C is
around 5%). Women receiving perinatal care are likely to be more motivated to
test and remained engaged in care.
In the United States, recommendations for hepatitis C
screening began to move from a risk-based screening approach to universal
screening from 2018, when the American Association for the Study of Liver Diseases
and the Infectious Diseases Society of America recommended screening of all
pregnant women. Other bodies have subsequently reinforced this guidance, but it
is not being implemented in all settings.
Reluctance to adopt universal screening is partly a consequence
of a lack of evidence regarding prevention of vertical transmission, as well as
the absence of clearly defined referral pathways in antenatal clinics for
maternal hepatitis C treatment.
University of Pittsburgh Medical Center began to implement universal
screening for hepatitis C during pregnancy in June 2020.
Dr Chappell presented a comparison of hepatitis C
screening and case detection during periods of risk-based and universal
screening in western Pennsylvania. The risk-based screening period chosen for
analysis was 2019; the universal screening period ran from 1 July 2020 to 30
June 2021.
During the risk-based screening period, 12,142 women entered
prenatal care. The study population was 19% Black, 72% White and 2% Hispanic.
Just under half (46%) were covered by Medicare or Medicaid health insurance.
During the universal screening period, 12,558 women entered care. Seventeen
per cent were Black, 74% White and 2% Hispanic. Forty-five per cent had Medicare
or Medicaid insurance.
Screening rates increased from 21% during risk-based
screening to 81% during universal screening. The rate of confirmatory HCV RNA
test also increased, from 22% to 95%, as a consequence of the use of reflex
testing (automatically performing an HCV RNA test on any sample that has shown
a positive HCV antibody result). During the risk-based screening period, eleven
women were diagnosed with chronic hepatitis, a prevalence of 0.091%. During the
universal screening period, 85 women were diagnosed with chronic hepatitis C, a
prevalence of 0.68%.
It wasn’t possible to link to infant health records in this
study, so the researchers estimated the number of infant hepatitis C cases
based on a published transmission rate of 5.8%. They estimate that one infant
with hepatitis C would have been identified as a result of risk-based screening
of mothers, compared with five as a consequence of universal screening.
“Universal screening resulted in a 7.5-fold increase in the
detection of chronic hepatitis C,” Dr Chappell concluded.
To establish a successful test-and-treat strategy for
hepatitis C in pregnancy, universal screening during pregnancy needs to be
accompanied by substance use treatment and hepatitis C treatment, she said.