Correctional facilities that test for hepatitis C virus (HCV) based only on major risk factors, including baby boomers (those born between 1945 and 1965) and people who inject drugs (PWID), miss many cases of the virus.

Publishing their findings in the American Journal of Preventive Medicine, researchers conducted a retrospective analysis of people entering the Washington state prison system between 2012 and 2016. That system offers routine opt-out HCV testing, in contrast with facilities that follow the Centers for Disease Control and Prevention (CDC) guidelines recommending a one-time test for baby boomers and screening for those with risk factors for the virus, such as injection drug use.

A total of 24,567 people were tested for HCV antibodies during this time, representing 83 percent of those who entered the state correctional system. Of those tests, 4,921 (20 percent) were positive. A total of 2,403 (49 percent) of those with a positive antibody test then received HCV RNA testing to confirm their infection, of whom 1,727 (72 percent) tested positive, indicating they were chronically infected with the virus. Of that group, 23 percent had at least moderate liver fibrosis.

Forty-four percent of baby boomers who were tested for HCV antibodies had a positive result, compared with 17 percent of those outside of this birth cohort. That said, 72 percent of positive HCV antibody results were among non–baby boomers.

The investigators estimated that following the more limited,targetedCDC testing guidelines rather than using a uniform opt-out testing policy would miss up to 35 percent of the positive HCV antibody tests among those entering correctional facilities.

“Routine testing at entry should be considered by U.S. state prisons,” the study authors concluded.

To read a press release about the study, click here.

To read the study, click here.