Only about 40% of perinatally exposed infants were tested for hepatitis C virus (HCV), and less than 30% of eligible children received HCV treatment, according to a large cohort study published in JAMA Network Open. 

Moreover, testing declined over the course of the study period and very few studies reported on the treatment of infected infants or factors related to testing. 

The odds of testing were higher for infants of at-risk birthing parents — those with public health insurance, HCV risk factors such as substance use disorder, housing instability, or an HCV diagnosis during delivery hospitalization — according to researchers led by Rachel L. Epstein, MD, MScE, a pediatric infectious disease specialist at Boston Medical Center and an assistant professor of medicine at Boston University in Massachusetts.

“Multiple studies have demonstrated that HCV testing in perinatally exposed children is low; however, few have had sufficient numbers or detailed covariates to investigate what factors predict lower or higher testing,” Epstein said. This study addressed both and showed testing trends over time. 

Study Details

Epstein’s group linked 4548 children born in Massachusetts during 2014-2021 to 3693 birthing parents with probable or confirmed HCV during 2011-2021. Of children born during 2014-2019 with confirmed perinatal HCV, 81.6% were linked to care, 65.8% had genotype testing, and fewer than 29% had evidence of HCV treatment by study’s end in 2022.

HCV was diagnosed in 2.5%; between 1 and 10 of 38 eligible children were treated by 2022. Testing decreased over time and was lowest for those born in 2020 at 32.3%.

Private insurance and private prenatal care correlated with lower odds of HCV testing, as did residence in rural counties. Testing was lowest in children of Black non-Hispanic birthing parents, whose babies were about 35% less likely to be tested than those born to their White non-Hispanic counterparts. 

Screening is important given that over two decades, HCV prevalence in pregnancy rose nearly 10-fold from 0.05% in 2000 to 0.49% in 2019, with perinatal infection occurring in approximately 8% of infants. 

Eliminating perinatal HCV transmission is now a priority of the US Viral Hepatitis National Strategic Plan.

HCV medications, however, have long been restricted by insurers, and many areas lack HCV-treating clinicians. “Reproductive-age women represent a particularly undertreated group, likely affecting the rising rates in pregnant people over the last two decades,” she said. 

Epstein said she was especially concerned about the decrease in testing from 2016 to 2022. It should be noted that the study’s results predate the CDC’s 2023 updated testing guidance.

Ravi Jhaveri, MD, head of pediatric infectious diseases at Ann & Robert H. Lurie Children's Hospital of Chicago and professor of pediatrics at Northwestern University Feinberg School of Medicine in Chicago, said, “The goal of the new [CDC] recommendation for PCR testing of infants at 2 to 6 months is to improve what had been the abysmal testing rates shown in this paper and others.” He was not involved in the current study.

One important question still to be addressed is who should do the testing. Historically, HCV specialists have seen these babies and ordered the testing, Epstein said. “However, so many people are lost to follow-up and not everyone can easily access a pediatric HCV specialist.”

While the CDC guidelines simplify the testing algorithm, they do not specify who should do the testing. “Education about the guidelines and the potential for infants going untested with reliance on referrals to care could help improve testing rates,” she said.

In a related commentary, Kathleen B. Schwarz, MD, a pediatric gastroenterologist at Rady Children’s Hospital, University of California San Diego, wrote, “Carefully done epidemiologic studies such as the current one by Epstein et al can be a powerful motivation to increase the number of children for whom treatment can confer lifelong benefits.” She noted the small minority of HCV-infected study children 3 years and older who were referred for treatment. “This is a travesty given that direct-acting antiviral therapy is FDA-approved for young children.” It is safe and effective and has also proven cost-effective, she wrote.

“We need to increase our efforts to ensure all pregnant people are HCV-tested during pregnancy, that results are communicated to pediatricians, and that pediatricians know to test or refer exposed infants for testing,” Epstein said. 

Epstein’s research was supported by the Charles A. King Trust, the Providence/Boston Center for AIDS Research, the National Institute on Drug Abuse (NIDA), the National Institute of Allergy and Infectious Diseases, and Boston University School of Medicine. Co-author Linas was supported by the Providence/Boston Center for AIDS Research and NIDA. Co-author Curtis received support from NIDA. Co-investigator Walley reported grant support from the CDC and the National Institutes of Health outside the submitted work; he disclosed honoraria from the American College of Academic Addiction Medicine, American Society of Addiction Medicine, and American Academy of Addiction Psychiatry outside of the submitted work. 

Schwarz received no funding for her editorial commentary. She reported consulting fees from Gilead and publishing royalties from UpToDate; she is the conflict of interest editor for the Journal of Pediatric Gastroenterology and Nutrition’s JPGN Reports.