Universal HCV screening in pregnancy: A step toward reducing transmission?

Universal screening for hepatitis C virus (HCV) in pregnant individuals resulted in improved detection and a potential reduction in perinatal transmission, according to a study presented at CROI 2022.

“Universal HCV screening resulted in a 7.5-fold increase in the detection rate of active HCV in pregnant people,” said study author Associate Professor Catherine Chapell from the University of Pittsburgh Medical Center (UPMC) Magee-Womens Hospital and University of Pittsburgh, Pittsburgh, Pennsylvania, US.

“Our study clearly shows that risk-based screening is insensitive for HCV detection in the general population,” she added.

Universal HCV screening was implemented in June 2020 at UPMC, where a reminder would be listed in the electronic medical records should HCV testing not be ordered in a new obstetrics panel. Reflex testing for HCV RNA was carried out for individuals who were HCV IgG positive.

The study comprised pregnant individuals presenting for prenatal care at UPMC. HCV testing was categorized as risk-based or universal screening, and the study compared 12,142 pregnant individuals undergoing risk-based screening* between January and December 2019 with 12,588 pregnant individuals undergoing universal screening between July 2020 and June 2021.

There was a significant increase in HCV IgG screening in individuals initiating obstetric care with the introduction of universal screening, rising from 23 percent to 81 percent (p<0.001). [CROI 2022, abstract 27]

There was also an increase in the detection of HCV IgG positive individuals, from 1.2 percent with risk-based screening to 1.9 percent with universal screening (p<0.001).

Twenty-two percent of individuals who were HCV IgG positive as per risk-based screening underwent HCV RNA testing compared with 95 percent of individuals who were HCV IgG positive according to universal screening.

There was a significant increase in the detection of active HCV through reflex HCV RNA testing, from 0.091 percent of those in the risk-based screening group to 0.68 percent of those in the universal screening group (n=11 vs 85; p<0.001).

As a result, more infants with perinatal HCV may have been identified in 12 months through universal screening whose cases may have been missed out in risk-based screening. “Using the published rate of perinatal HCV transmission [5.8 percent] and assuming all exposed infants were tested, only one infant was identified using risk-based screening and five with universal screening,” said Chapell.

“Pregnancy is a critical window of opportunity for engagement in the HCV care cascade and pregnant people must be included in the HCV elimination strategy,” Chapell noted.

“Identifying all cases of HCV in pregnant people can facilitate linkage to care and treatment for pregnant people and provide treatment prior to liver disease, cirrhosis, liver transplant, and hepatocellular carcinoma. Similarly, identifying all infants exposed will allow for timely detection of perinatal HCV transmission and early linkage to care and treatment … and [prevent] development of chronic HCV infection.”

While universal HCV screening is the first step toward this goal, HCV treatment during pregnancy is crucial, she highlighted.

Chapell acknowledged the single-centre design and potential variation in screening practices with different healthcare providers as limitations. Furthermore, the inability to link infant records in this study resulted in an estimation of the perinatal HCV transmission rate.