Birth-cohort screening for hepatitis C virus according to U.S. Centers for Disease Control and Prevention guidelines may miss around one-quarter of infections, researchers said.
An 8-week seroprevalence survey in an urban emergency department tested excess blood samples from 4,713 patients for hepatitis C virus, finding an overall prevalence of 13.8%, of which 31.3% was undocumented infection.
According to a paper published in Clinical Infectious Diseases, among the 204 patients with undocumented HCV infection, 48.5% were born between 1945 and 1965 and therefore would have been included in birth-cohort testing, and 26.5% would have been picked up for risk-based testing.
But 25% of the patients found to be infected with HCV in the study would not have been tested based on birth cohort or risk (Clin Infect Dis. 2016 Feb 21. doi: 10.1093/cid/ciw074).
The CDC added the recommendation for one-time testing of individuals born between 1945 and 1965 to its existing advice on risk-based screening in 2012, and this was backed by the U.S. Preventive Services Task Force in 2013.
“Since the CDC’s revised HIV testing recommendations for the health care settings were released, many EDs have had great success in implementing routine HIV testing to the population they serve over the past decade,” wrote Dr. Yu-Hsiang Hsieh of Johns Hopkins University, Baltimore, and coauthors. “This coupled with the availability of effective therapeutics makes EDs a key and strategic component of the national plan to expand HCV testing.”
At the same time, a second study, also in an urban emergency department, tested samples from 924 individuals enrolled in an HIV prevalence survey.
In this study, published in the same issue of Clinical Infectious Diseases, researchers found HCV antibodies in samples from 128 patients (14%); 34% of whom self-reported a history of HCV or hepatitis and 81% of whom were RNA positive.
The researchers noted, however, that, had they only implemented birth-cohort or risk-based screening, they would have missed 28% of individuals with antibodies and 25% of individuals with replicative HCV.
In this study, individuals with HCV infection were more likely to report injection drug use and high-risk sexual behavior, even among individuals reporting neither of these risk factors, but the prevalence of HCV infection was 7% (Clin Infect Dis. 2016 Feb 21. doi: 10.1093/cid/ciw073).
“We also cannot compare our results with the epidemiology of the surrounding population not using the ED, but suggest that as is the case with HIV, EDs are likely to provide a uniquely high level of access to populations with undiagnosed HCV who are in need of treatment,” wrote Dr. Michael S. Lyons and colleagues from the University of Cincinnati.
The authors, however, suggested that their survey may have underestimated the current prevalence of HCV because of an increase in heroin use in the area in more recent years.
Dr. Hsieh and colleagues suggested there was a need to revise the CDC recommendations and expand the age cut-off to all individuals aged 18 years or over.
The first study was supported by the National Institutes of Health and the authors declared no conflicts of interest. The second study was partly supported by Gilead Sciences, the National Institutes of Health, and Bristol-Myers Squibb. Four of the seven authors reported support, research grants, consultancies, or advisory board positions with pharmaceutical companies including Gilead and Bristol-Myers Squibb.