O112: Screening: saliva and blood‐based screening assays

Abstract

In the United States, mortality associated with hepatitis C is on the rise and it has been estimated that 3.2-4 million persons in the United States have chronic HCV infection. In 1998, CDC recommended a risk-based approach to screening, with routine HCV testing for persons with risk factors including injection drug use, having received clotting factor concentrates produced before 1987, being on chronic hemodialysis, having persistently abnormal alanine aminotransferase levels, being a recipient of donated blood from a person who tested positive for HCV, or having received a blood transfusion or organ transplant before July 1992; in 1999, CDC recommended HCV testing for persons with HIV. However, risk-based screening strategies can be limited either by clinician reluctance to ask about risk factors or by patient unawareness or reluctance to disclose risk behaviors. As a result, use of risk-based strategies alone has resulted in a large proportion of infected persons remaining undiagnosed; in the United States, various estimates indicate that 45-85% of persons with HCV are unaware of their infection status. To augment risk-based screening, in 2012 CDC published a recommendation for one-time testing without prior ascertainment of HCV risk for persons born during 1945- 1965. This birth-cohort approach was designed to both target persons with the highest prevalence of HCV infection and remove any behavioral stigma from screening. It has been estimated that with implementation of the birth-cohort screening strategy, 121,000 deaths from HCV will be averted and that screening is cost effective. Recently the USPSTF issued a final recommendation regarding HCV testing, assigning a Grade B to two recommendations: screening for HCV infection in persons at high risk for infection and one-time HCV screening for adults born between 1945 and 1965. Approximately 79 million persons were born during 1945-1965 (the Baby Boom Generation), making birthcohort based screening a daunting task. Patients should first be tested for HCV antibody and those who are reactive for HCV antibody should next be tested with an FDA-approved nucleic acid testing assay for detection of HCV RNA indicative of current HCV infection. Rapid tests for HCV antibody allow access to HCV testing in settings lacking laboratorybased diagnostic services. Rapid tests for HCV antibody detection include OraQuick, which is approved by the FDA, as well as Chembio, MedMira and mBio, which are under development. In this talk we will evaluate both the rationale and implementation of screening for HCV and how to integrate novel technologies into the careening paradigm.