Theme: Clinical Research Year: 2019
Background and Aims: Point-of-care testing (POCT) for hepatitis C (HCV) increases access to screening for hard-to-reach
populations. OraQuick HCV Rapid Antibody POCT (OQ) requires waiting 20 minutes before interpreting results; however,
field observations suggest a shorter read-time is sufficient for viremic individuals (VIs). Our aim is to determine if viremic
samples reliably activate the test band prior 20 minutes and if so, to establish an earlier cut-off.
Method: Blood samples from 109 HCV VIs and 32 long-term resolvers (LTRs, defined as clearing HCV > 3 years prior)
were tested with OQ. Photos were taken every 15 seconds for 20 minutes; time of a visible positive band was recorded
and confirmed by a second reader. Band intensities at each minute were compared to final intensity at 20 minutes (n =
20). Negative controls included 6 uninfected subjects. Data collection is ongoing.
Results: All VIs were positive before 5 minutes (n = 109). Mean time to positivity was 2.6 minutes in VIs, compared to 5.6
minutes in LTRs (p < 0.0001). VIs were 61% male, median age of 59, median HCV RNA of 2.71x10^6 IU/ml, and 25 had
cirrhosis. LTRs cleared HCV 5-14 years prior, following treatment; all were cirrhotic. 16 of 31 LTRs were positive at 5
minutes. Probability of a VI testing positive by 5 minutes was 100% (98% CI, 0.97-1.00). Analysis of band intensity
showed that VI bands darken within 5 minutes to 52% (+/- 14%) of their final intensities.
Conclusion: OQ can reliably detect anti-HCV Abs within 5 minutes for VIs. There may be value in documenting past HCV
infection; however, the main goal of screening is to identify those infected. This shortened read-time may have
important implications to improve engagement and linkage to care by facilitating follow-up HCV RNA in as few as 5
minutes.
Disclosure of Interest Statement: NIL