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From Prevention in Focus, Spring 2017
Hepatitis C point of care testing: What is its impact on testing and
linkage to care?
By Suzanne Fish
With the advent of new, highly effective treatments, one of the major challenges in addressing the hepatitis C
epidemic is related to testing and linkage to care. It is estimated that over 220,000 people in Canada are chronically
1
infected with the hepatitis C virus and over 40% do not know they are infected. Innovations and advances in
testing and linkage to care are essential in addressing the hepatitis C epidemic. One such innovation is the rapid
point-of-care test for hepatitis C virus antibodies. One test has been licensed by Health Canada.
This article outlines how rapid point-of-care testing can improve testing and linkage to care, reviews the scientific
literature related to the rapid test approved by Health Canada, and details if and how this test or others can impact
the hepatitis C epidemic in Canada.
What is the current hepatitis C testing landscape in Canada?
Testing in Canada for hepatitis C typically comprises a two-step process: a laboratory-based antibody test and then
2
a confirmatory test. These laboratory-based antibody and confirmatory tests are very accurate. First a person is
tested for hepatitis C antibodies through a blood draw. The blood sample is sent to a laboratory and results are
available in one to three weeks. A positive result for hepatitis C antibodies shows that the person has been exposed
to the hepatitis C virus (HCV). This does not mean that they have an active hepatitis C infection, because antibodies
will remain in the blood even if a person has been cured of hepatitis C through treatment or if the person's own
immune system has cleared the infection.
If someone receives a positive test result for antibodies, then they engage in the second step of the process, which
involves a second blood draw. A laboratory test is used to confirm the presence of an active hepatitis C infection.
There are two types of confirmatory tests. The hepatitis C RNA test checks for the presence of the hepatitis C
virus in the body by measuring the genetic material (RNA) of the virus in the blood. If a person tests positive for
hepatitis C RNA it means they have an active hepatitis C infection. A third appointment is needed to get the
confirmatory test result.
The second type of confirmatory testing is not widely available in Canada. This test is the hepatitis C core antigen
test, which checks for the core antigen, a protein that is part of the hepatitis C virus. If a person tests positive for
hepatitis C core antigen it means they have an active hepatitis C infection (however, there is a risk of a false-negative
test). This test can be done on the same blood sample as the original hepatitis C antibody test. This means that
sometimes the number of visits involved in hepatitis C testing can be reduced.
What is a point-of-care test?
A point-of-care test is a rapid testing technology that allows people to be tested and learn the results during the
same visit. These screening tests are performed outside of the clinical laboratory and instead are performed where
the patient is receiving care. Point-of care tests can be administered and interpreted by non-specialists including
3
family doctors and nurse practitioners and even non-medical staff like frontline workers and peers. They can also
345
be delivered in a variety of settings including non-medicalized settings like community-based organizations. , ,
A point-of-care test for hepatitis C can simplify the testing process and may provide less opportunity for people to
6789
be lost to follow up after confirmatory testing and they may remain engaged in care. , , , Point-of-care tests may
also increase the number of people tested, since tests can be administered and interpreted outside of medical
9 10 11 12 13 14
facilities and in remote settings. , , , , , This is especially important for populations who do not have equitable
access to health care.
Why is a point-of-care test needed for hepatitis C?
While the current hepatitis C blood testing system provides diagnostic accuracy, the two-step laboratory process
can result in people being lost to confirmatory testing. The hepatitis C treatment cascade, sometimes called the
continuum of care, may be one useful way to assess how well our current hepatitis C care practices are working.
While numbers for the hepatitis C treatment cascade are not available in Canada, a model from the United States
was published in 2014. This model estimated that only 50% of the people living with chronic hepatitis C in the United
States are aware of their status, only 27% have a confirmed positive test, and only 16% have been prescribed
15
treatment.
This data is similar to estimates from Canada – over 220,000 people in Canada are chronically infected
1
with HCV and only 56% are aware of their status. These data support that we are falling short, specifically in the
area of testing, and that we need new approaches to find the undiagnosed. This can include new programming
approaches and the application of new technologies.
What are the barriers to hepatitis C testing?
Many of the priority populations most affected by hepatitis C in Canada experience significant barriers to hepatitis C
10 16
testing. Studies among these populations found that logistical barriers, such as lack of time to test , and lack of
10
transportation to testing locations,
prevented people from testing for hepatitis C. Individual-level barriers such as
16 17
17
lack of knowledge about hepatitis C in general, ,
hepatitis C testing in particular, misperception about one’s
17
16
10 18
own risk,
lack of understanding about transmission routes, and fear of the result , were also identified as
barriers to testing. Studies have also identified barriers related to the healthcare system, including lack of confidence
16 17 18
16
in care , , and a lack of culturally appropriate services.
The two-step testing process for hepatitis C can also create barriers due to its requirement for multiple visits,
6 19 20 21
multiple blood draws and the confusion it creates for healthcare providers and patients. , , ,
Overview of the point-of-care hepatitis C test
Since the 1990s, several hepatitis C point-of-care tests have been developed that use blood or oral fluid to test for
22
hepatitis C antibodies. Performance varies widely among the tests.
One of these tests was developed by a U.S. company called OraSure Technologies. This company has developed a
rapid oral fluid and fingerstick (blood-based) test for HCV antibodies called OraQuick. OraQuick HCV is a single-use
point-of-care test for hepatitis C antibodies. It provides results in 20 to 40 minutes. The Oraquick HCV test can use
23
either oral fluid or fingerstick whole blood and can detect antibodies to all hepatitis C genotypes. Based on the
comparative efficacy of the different tests that have been developed, OraQuick demonstrates the highest potential
24
to be used as a rapid screening test for hepatitis C infection.
The OraQuick HCV fingerstick test was licensed by Health Canada in January 2017. It has also been approved by the
United States Food and Drug Administration for use in the United States and by the European Union CE (European
Conformity) marking, which signifies that the product complies with the essential requirements of the relevant
European health and safety legislation.
Accuracy of OraQuick HCV tests
In order to determine the accuracy of the Oraquick HCV test, several studies have been done to evaluate the
sensitivity (the proportion of positive test results that are correctly identified) and the specificity (the proportion of
negative test results that are correctly identified) of the OraQuick HCV test. Eleven studies showed that the
25
OraQuick HCV test has very high sensitivity and specificity.
Table 1. Sensitivity and specificity of OraQuick HCV tests through different fluids
Sensitivity (%)Specificity (%)
Oral fluid
90.8 – 99.2
92.1 – 100.0
Whole blood
94.4 – 100.0
98.8 – 100.0
Fingerstick blood95.9 – 100.0
99.9 – 100.0
Compared to the most common type of laboratory-based hepatitis C antibody test – the third-generation enzyme
immunoassay – the sensitivity and specificity of the fingerstick blood OraQuick HCV test is slightly lower but
somewhat comparable. However, the sensitivity and specificity of the oral fluid test is lower. Third-generation
25
enzyme immunoassays have a diagnostic sensitivity and specificity of greater than 99%.
Linkage to care
Rapid point-of-care hepatitis C testing programs may increase linkage to care rates among people whose hepatitis C
screening test is reactive (positive). A study done in 2012 and 2013 in Connecticut found that of the patients with a
positive hepatitis C antibody test, people who chose the rapid test were significantly more likely to be linked to
12
hepatitis C specialty care than those who chose traditional laboratory testing (93.8% compared with 18.2%).
Another study that offered rapid hepatitis C testing to clients at a sexually transmitted infections clinic found that
98% of clients who were antibody positive returned to receive follow-up testing. Of those with chronic infection who
9
returned for their results, 85% were referred to care and 52% attended a specialist appointment.
A program that provided rapid hepatitis C screening in community-based settings in a high prevalence
neighbourhood of Philadelphia found that 87% of those whose screening test was antibody positive returned for a
confirmatory test. Of those clients with a chronic hepatitis C infection who had a primary care provider, 75% were
7
referred to specialist care, and 91% of these attended their first appointment.
A randomized controlled trial that compared rapid testing of hepatitis C, HIV and hepatitis B to standard blood tests
found that, overall, 90% of clients who tested positive in the rapid test arm of the trial were linked to care, compared
26
to 83% in the blood test arm. Although this may be clinically significant, it was not statistically significant.
Cost effectiveness
Little cost-effectiveness research has been conducted that compares rapid hepatitis C testing to standard laboratory
27
tests. One study found the cost of rapid testing and traditional laboratory testing comparable. A second study
compared two cost-effectiveness strategies in a substance use treatment setting. The study found that it was more
28
cost effective to offer clients onsite rapid testing than to refer out to hepatitis C testing in the community.
Are hepatitis C point-of-care tests acceptable and preferable to clients?
Hepatitis C point-of-care tests seem acceptable to clients. When asked, study participants cited same day results as
26
the most common reason for their preference.
A survey-based study among people who use drugs that measured the acceptability of rapid hepatitis C tests found
29
that 85% of respondents found rapid testing for hepatitis C acceptable. Another study among clients without
health coverage attending a free clinic measured preference for rapid tests compared to laboratory tests. It found
that 76% of clients preferred a rapid test to a standard laboratory test for hepatitis C and other blood-borne
26
infections.
Do service providers prefer point-of-care hepatitis C tests?
Hepatitis C point-of-care tests are preferred by some service providers.
One study found a high preference for the OraQuick HCV point-of-care test among service providers in communitybased settings serving priority populations in New York City. In this study 99% of service providers preferred the
6
point-of-care test over standard antibody testing. Five of these community-based organizations (CBOs) provided
services to people who use injection drugs and two provided services to immigrant populations from hepatitis C
endemic countries. Reported benefits included the ease of specimen collection in community-based settings, fewer
needle-stick injuries, a single visit for antibody testing and results, which meant more referrals for confirmatory
6
tests and linkage to care, and a higher volume of tests could be conducted.
Implications for service providers
Hepatitis C point-of care-tests have the potential to increase the numbers of people who get tested and linked to
care. These quick, simple and relatively non-invasive antibody tests can be easily used in non-traditional healthcare
settings. This can improve accessibility of the test, especially for populations that have infrequent and unreliable
engagement with mainstream health services.
While hepatitis C point-of-care tests provide much promise in terms of increasing access to testing and improving
linkage to care amongst priority populations, the effectiveness and impact of these tests depends on how well this
technology is integrated into comprehensive hepatitis C programming across the continuum of care. Although pointof-care tests provide a quick and relatively simple antibody test, a confirmatory test is still required. As such, it is still
critical to follow-up with patients and find ways of supporting patients to return for test results and continuing care.
While point-of-care tests limit the number of medical visits required to confirm a patient’s hepatitis C status, multiple
visits are still required. It is critical to find ways of making appointments accessible and also to explore creative ways
of supporting clients to attend appointments – including supporting them with transportation, reminders and
accompaniment. Developing services that are culturally safe and client centred can also prevent loss to follow up.
While testing is an essential step in the continuum of care, it is also critical that patients are linked to specialty care
upon diagnosis. Affordable treatments and appropriate programming developed by and for the priority populations
are critical pieces in the process, along with prevention technologies and programs. Point-of-care tests have the
potential to diagnose larger numbers of Canadians. The key will be to link these populations with appropriate,
affordable, comprehensive and timely treatment and care both pre- and post-testing.
One clinic in Vancouver demonstrated the impact that rapid point-of-care hepatitis C tests can have in highprevalence communities. Vancouver Infectious Diseases Clinic uses rapid hepatitis C testing at outreach pop-up
clinics as a way to test and diagnosis people who are exposed to hepatitis C on an ongoing basis and then links
those who test antibody positive to hepatitis C confirmatory testing and care.
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About the author(s)
Suzanne Fish works at CATIE as the knowledge broker in hepatitis C, community health programming. Suzanne
has an M.A in Political Economy and has spent the past 10 years engaged in health equity and community
engagement initiatives with a range of social service agencies, community organizations and grassroots civil society
groups around the globe. She has focused her research and social justice work on centring insights from lived
experience and evidence-based interventions within project, program and policy-development arenas.
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