A study of more than 4,500 US infants exposed to hepatitis C virus (HCV) in utero or at birth from 2014 to 2021 finds that only 42% were later tested for the potentially serious but highly treatable infection, and few received the recommended treatment.
A team led by Boston University researchers used a statewide health database to explore factors tied to HCV testing of perinatally exposed infants in Massachusetts and estimated the proportion of infants diagnosed as having perinatal HCV infection who then receive care. They published their findings late last week in JAMA Network Open.
Perinatal HCV infection, which occurs in about 8% of exposed infants, is the most common route of HCV transmission in children, the authors noted.
“In October 2023, the CDC [Centers for Disease Control and Prevention] recommended RNA testing for infants exposed to HCV between ages 2 and 6 months to reduce loss to follow-up before later antibody testing,” they wrote. “While we await data on testing practices following the new guidelines, understanding factors associated with improved testing could shape interventions to implement these recommendations.”
Nearly 3% of infants tested received HCV diagnosis
The annual proportion of infants exposed to HCV (as a percentage of all live births in Massachusetts) rose from 0.73% (509 births) in 2014 to 1.34% (700) in 2020, declining to 1.1% in 2021.
Among the 4,103 children born to 3,419 mothers with probable or confirmed HCV infection, only 41.9% of exposed infants were tested. HCV was diagnosed in 2.5% of infants tested. Appropriate HCV testing rates declined over time; 45.7% of infants born in 2014 were tested, compared with only 32.3% of those born in 2020.
By December 2022, 46.4% of exposed children had undergone any HCV testing, and 41.9% completed appropriate testing (RNA testing starting at 2 months of age or antibody testing starting at 18 months).
Of those who completed appropriate testing, 48.7% had antibody testing alone, 30.9% underwent RNA testing, and 20.3% had both antibody and RNA testing. The proportion appropriately tested varied by county (from 32.5% to 48.5%) and birthing hospital (27.1% to 67.4%).
Only 56.2% of deliveries had HCV recorded in birth certificate data, and 79.6% had a claim for the mother’s HCV diagnosis during the delivery hospitalization. Histories of housing instability or homelessness (77.6%), incarceration (37.3%), mental illness (84.8%), and substance use disorders (72.4%) were prevalent.
A health care claim for the mother’s HCV infection within 30 days of delivery (adjusted odds ratio [aOR], 5.40), a prescription for medication for opioid use disorder during pregnancy (aOR, 1.29), and factors correlated with HCV risk were linked to significantly greater chances of appropriate testing. Risk factors for lower testing probability were Black race (aOR, 0.65) and private health insurance (aOR, 0.76).
Less than a third received treatment
Of 38 children with perinatal HCV who were 3.5 years or older by study end in 2022, 81.6% were linked to care, 65.8% underwent genotype testing, and less than 29.0% had evidence of HCV treatment.
A 2025 study found 51% of children referred for HCV treatment could not swallow pills upon referral.
One barrier to care is the lack of liquid HCV treatment regimens for children; rather, the only available treatments consist of bitter granules or pellets that require administration with food, the researchers said.
“A 2025 study found 51% of children referred for HCV treatment could not swallow pills upon referral,” they wrote. “While 92% achieved SVR [sustained virologic response], approaching clinical trial SVR rates, not all settings have specialized pharmacy teams to facilitate medication approvals and swallowing practice. Additionally, there are relatively few pediatric HCV specialists.”
The findings suggest that many more infants are untested because their mother’s HCV infection status is unknown. “It is critical that (1) we test all pregnant people for HCV, (2) prenatal clinicians communicate HCV results to pediatricians, and (3) pediatricians check prenatal HCV testing results routinely for all children, regardless of background or perceived HCV risk, to ensure all exposed children are identified and tested,” the authors wrote.
Point-of-care test unavailable for kids
In a related commentary, Kathleen Schwarz, MD, of the University of California San Diego, said that pediatricians were frustrated to learn that the 2024 US Food and Drug Administration approval of a point-of-care HCV RNA test was restricted to patients aged 22 years and older.
