Rapid HIV tests are simple to use and require little or no specialized
equipment. They make it possible to provide test results at the time the
test is done. Six rapid HIV tests approved by the U.S. Food and Drug
Administration (FDA) are commercially available for use in the United
States (listed in chronological order of their FDA approval dates):
-
OraQuick Rapid HIV-1/2
Antibody Test
-
Reveal G3 Rapid HIV-1
Antibody Test
-
Uni-Gold
Recombigen HIV Test
-
Multispot
HIV-1/HIV-2 Rapid Test
-
Clearview HIV 1/2
Stat Pak
-
Clearview Complete HIV 1/2
*Manufacturer has applied for waiver for use with
whole blood.
Requirements for Performing Rapid HIV Tests
Any organization that performs a rapid HIV test in order to provide
results to patients is considered a laboratory under the Clinical
Laboratory Improvement Amendments of 1988 (CLIA). All laboratories must
comply with the regulations of the CLIA program and with applicable
state requirements. (For more information on CLIA, which is administered
by the Centers for Medicare & Medicaid Services (CMS), and a list of
laboratory contact persons in each state, visit the
CMS CLIA Web site.
An organization can either apply for its own CLIA certificate or, if
authorized by CMS, make arrangements to be included with a CLIA-certified
laboratory under a multiple-site exception.
The sale of rapid HIV tests is restricted to clinical
laboratories that have an adequate quality assurance program and
where persons who use the test will receive and use the
instructional materials provided with the tests. The FDA also
requires that persons tested with the rapid tests receive the
"Subject Information" pamphlet provided with the test. Details
about other restrictions that apply to the rapid HIV tests are
outlined in the package inserts provided with the test kits.
Currently available
rapid HIV tests are either “waived” or
categorized as “moderate
complexity” under the CLIA program.
CLIA requirements for laboratories differ depending on the
category of the test.
Waived Testing
OraQuick is a waived test when it is used with whole blood or oral
fluids. Uni-Gold and Clearview HIV 1/2 Stat Pak are waived tests when used with
whole blood. The manufacturer of Clearview Complete HIV 1/2 test has
applied for a CLIA waiver.
For waived tests, there are no federal requirements for personnel, quality
assessment, or proficiency testing. Waived tests can be done in
traditional laboratories or clinical settings and also in settings such
as doctors' offices, HIV counseling and testing sites, mobile vans, and
health fairs. To perform waived tests, an organization must obtain a
certificate of waiver from the CLIA program (or, if authorized by CMS,
be included with a CLIA-certified laboratory under a multiple-site
exception) and follow the manufacturer's instructions for the test
procedure. For laboratories that plan to perform waived testing, more
information on CLIA requirements is outlined in the CLIA
Certificate of Waiver Fact Sheet and at the
CDC CLIA Web site. CDC
also has developed guidelines on quality
assurance practices for laboratories planning to use waived HIV
rapid tests.
Moderate Complexity Testing
Reveal and Multispot are categorized as moderate complexity tests.
OraQuick is categorized as moderate complexity when used with plasma.
Uni-Gold, Clearview HIV Complete HIV 1/2, and Clearview HIV 1/2 Stat Pak are categorized as
moderate complexity when used with serum or plasma.
A laboratory that performs moderate complexity tests must register with
the CLIA program and meet specific CLIA standards for personnel, quality
assessment, proficiency testing, and inspections. For organizations that
plan to perform moderate complexity testing, more information on CLIA
requirements and the steps necessary to obtain a certificate for
moderate complexity testing are outlined in the
moderate
complexity overview section of the CDC CLIA Web site.
Summary of the Testing Procedures
OraQuick
Advance Rapid HIV 1/2 Antibody Test
The
OraQuick test
is
approved for use with whole blood specimens obtained by fingerstick or
by venipuncture, with oral fluid specimens, and with plasma. It is
intended for use at point of care, in medical and nonmedical settings.
However, it can also be performed in a laboratory after the specimen has
been obtained.
To conduct the test, place a vial of developer solution in the plastic
stand. The reusable stand holds the test device at the correct angle to
ensure accurate test results. When testing a fingerstick specimen, clean
the fingertip with alcohol and prick the fingertip with a lancet
(needle) to get a small drop of blood. The blood is collected with a
specimen loop and transferred to a small plastic vial containing a
premeasured volume of developing solution, into which the sample is
mixed. The testing process is the same for whole blood or plasma
obtained by venipuncture. For whole blood, insert the specimen loop into
the tube of blood after the tube has been inverted to ensure that the
blood is thoroughly mixed. For plasma, first centrifuge the blood to
separate the blood cells from plasma, and insert the specimen loop into
the plasma. Then insert the specimen loop into the test vial and mix.
Collect oral fluid specimens by using the absorbent pad on the end of
the test device to swab the outer surface of the upper and lower gums.
Then insert the test device into the test vial. Test results must be
read no sooner than 20 minutes, but no later than 40 minutes, after the
OraQuick device is added to the developer solution.
The
test result is read directly from
the OraQuick device.
- If 1 reddish band appears at the control (C) location the
test result is negative for HIV antibodies.
- If 2 reddish bands appear,
one at the control (C) location and one at the test (T) location,
the test is “reactive” (that
is to say, the test result is preliminary positive for HIV-1 or HIV-2
antibodies).
- If no band appears at the C location, if any bands appear
outside the C or T locations, or if a pink-red background appears
in the device window, the test is invalid and must be repeated.
The OraQuick test includes an internal control that verifies that specimen
has been added and that the test has been run correctly, Positive and
negative external controls must be run by each new operator before
performing testing on patient specimens, whenever a new lot of test kits
is used, if the conditions of testing or storage (e.g., temperature)
fall outside the range recommended by the manufacturer, and at periodic
intervals specified in the laboratory's quality assurance program.
External controls are not included with the test kits and must be
ordered separately from the manufacturer.
Shelf Life of Kits:
6 months from data of manufacture if stored at room temperature
Shelf Life of
Controls: 1 year unopened or 8 weeks after opening if refrigerated
For more information
on the OraQuick test, see the test kit
package insert or
visit the manufacturer’s Web site.
Reveal G3 Rapid HIV-1 Antibody Test
The Reveal G3 test
is intended for use as
a point-of-care test, but it requires some laboratory equipment.
Positive and negative external controls (supplied with the test) must be
reconstituted with buffer solution. These control reagents, each
sufficient for 5 tests, can be stored refrigerated for up to 7 days
after they are reconstituted. To do
the test, draw a blood specimen from a vein and centrifuge the specimen
to separate the blood cells from the serum or plasma. Place a buffer
solution in the test cartridge, and allow it to be absorbed. Add the
serum or plasma specimen to the test cartridge and allow it to be
absorbed. Then place the InstaGold cap in the cartridge and add 12 drops
of buffer.
Then
remove the cap and read
the
test result directly from the cartridge.
An
additional 3 drops of buffer may be added to clarify the test results
- A red band on the test
cartridge indicates the test result is “non-reactive,” that
is, negative for HIV-1 antibodies.
- A
red dot with a red band on the test cartridge indicates
the test result is “reactive,” that is, preliminary
positive for HIV-1 antibodies.
- Absence of the red band on the test cartridge after the
test has been run, or a pinkish-red background throughout the window
of the cartridge indicates that the test is invalid and must be repeated.
Unlike the Reveal test initially approved by the FDA, the Reveal G3 test
contains an internal procedural control that verifies that the specimen
has been added and the test has been run correctly. External controls
(known HIV-positive and -negative specimens supplied with the test kit)
must be run by each new operator before performing testing on patient
specimens, whenever a new lot of test kits is used, if the conditions of
testing or storage (e.g., temperature) fall outside the range
recommended by the manufacturer, and at periodic intervals specified in
the laboratory's quality assurance program.
Shelf Life: 12 months from date of manufacture if stored at room temperature.
For more information
on the Reveal G3 test, see the test kit
package
insert or visit
the manufacturer’s
Web site
Uni-Gold Recombigen
HIV
The Uni-Gold test
is a single-use rapid test for
the detection of HIV-1 antibodies in plasma, serum, or anticoagulated whole
blood obtained by fingerstick or venipuncture. It is intended for use as a
point-of-care test.
To
conduct the test, draw an adequate specimen (serum, plasma, or whole
blood) to the first gradation on the pipette supplied with the kit, or
obtain a fingerstick blood specimen with the pipette supplied for this
purpose. Hold the pipette vertically over the sample port and add 1 drop
of specimen. Add 4 drops of the wash solution from the dropper bottle to
the sample port. Set timer for 10 minutes..
The
test result is read directly from the device 10 to 12 minutes after
the specimen is added.
- A reddish line at the “control” region
with no line at the “test” region indicates that the test is
negative for HIV-1 antibodies.
- A reddish line of any
intensity at both the “test” and “control” regions
indicates the test is “reactive”, that is, preliminary positive
for HIV-1 antibodies.
- No line at the “control” region (irrespective
of a line forming at the “test” region) or lines not adjacent
to the respective regions indicate the test is invalid and must be repeated
The Uni-Gold
test includes an internal control that indicates whether the test is functioning
correctly. However, the formation of the control line on the Uni-Gold test does
not validate that the specimen has been added to the test. Consequently, a test
with no specimen added may appear the same as a test with a negative result
(that is, a band in the control region and no band in the test region). When
testing whole blood, you must observe the red color at the specimen sample port
to validate that specimen was added. Positive and negative external controls
should be run by each new operator before performing testing on patient
specimens, whenever a new lot of test kits is used, if the conditions of testing
or storage (e.g., temperature) fall outside the range recommended by the
manufacturer, and at periodic intervals specified in the laboratory's quality
assurance program. External controls are not included with the test kits and
must be ordered separately from the manufacturer. The controls require
refrigeration and can be stored for 21 days after they are opened.
Shelf Life of Kits:
1 year from date of manufacture if stored at room temperature
For more information on the Uni-Gold test, see
the test kit package
insert or
visit the manufacturer’s
Web site.
Multispot
HIV-1/HIV-2 Rapid Test
The Multispot
test is a single-use rapid test that detects and
differentiates circulating antibodies to HIV types 1 and 2 in fresh or
frozen human serum and plasma. It has been approved by FDA to
differentiate HIV-1 from HIV-2 antibodies. Multispot requires a
refrigerator for the reagents and some laboratory equipment for
processing and diluting the specimen.
To conduct the test,
-
Dilute the
specimen in specimen diluent and then add it to the test cartridge
through a prefilter.
-
After the
diluted specimen has been completely absorbed, remove the prefilter. If
antibodies against HIV-1 and/or HIV-2 are present in the specimen, they
bind to the antigens on the microparticles in the specific spots on the
cartridge membrane.
-
Add the
conjugate to the cartridge. The conjugate binds to the human
antibody-antigen complexes that are immobilized in the spots on the
cartridge membrane.
-
Perform a wash
step to remove the unbound conjugate
-
Add development
reagent and a stop solution to the cartridge.
-
Examine the
membrane visually for the presence of the color purple on the procedural
control spot and on the test spots.
The test result is
read directly from the device at any time after the test is completed.
-
The purple color
on the test spots is proportionate to the amount of antibodies against
HIV-1 and/or HIV-2 that have been bound to the antigen-coated microparticles
and detected by the conjugate.
- The procedural
control spot will turn purple when the test has been performed
correctly. If no color appears at the control spot, the test is invalid
and must be repeated with a new cartridge.
Shelf Life of Kits:
1 year refrigerated, 3 months at room temperature
For more information on the Multispot test, see
the test kit
package
insert or
visit the
manufacturer's Web site.
ClearView HIV 1/2 Stat Pak
The
Clearview HIV 1/2 Stat Pak is a single-use rapid test that
detects antibodies to HIV-1 and HIV-2 in fingerstick whole blood, venous
whole blood, serum, or plasma specimens. The Clearview HIV 1/2 Stat Pak assay is
intended for use as a point-of-care test to aid in the diagnosis of
infection with HIV-1 or HIV-2
To conduct the test,
- Place the
Clearview HIV 1/2 Stat Pak cartridge on a flat surface.
- Label the test device
with patient name or identification number.
- Touch the 5 µL
sample loop (provided in kit) to the specimen, allowing the specimen to
fill the opening of the loop.
- Holding the
sample loop vertically, touch it to the sample pad in the center of the
sample (S) well of the device to dispense about 5 µL of specimen onto
the sample pad.
- Invert the
bottle of running buffer bottle and hold it vertically over the sample
well. Add 3 drops (about 105 µL) of buffer slowly, drop by drop, into
the sample (S) well.
-
Wait
15 minutes.
The test result is
read directly from the device.
-
Read the test results after 15 to 20 minutes. Reactive test results
may be observed and read earlier than 15 minutes. To verify a
nonreactive test result, wait the entire 15 minutes. Do not read
results after 20 minutes.
-
A reactive test will show two pink or purple lines—1 in the test area
and 1 in the control area. The line in the test area may look
different from the line in the control area. Intensities of the test
and control lines may vary, but a test result with visible lines in
both the test and control areas, regardless of intensity, is
considered reactive, which means that HIV-1 and/or HIV-2 antibodies
have been detected in the specimen. The test result is interpreted
as preliminarily positive for HIV-1 and/or HIV-2 antibodies.
-
A nonreactive test will have 1 pink/purple line in the control area,
but no line in the test area. A nonreactive test result means that
neither HIV-1 nor HIV-2 antibodies were detected in the specimen.
The test result is interpreted as negative for both antibodies.
-
The test is invalid if there is no pink-purple line in the control
area. Similarly, the test is invalid if any lines appear outside the
control area or test area. An invalid test cannot be interpreted. An
invalid test must be repeated with a new device.
Shelf Life of Kits:
24 months from the date of manufacture if stored at room temperature
For more information on the Clearview HIV 1/2 Stat Pak, see
the test kit
package insert or
visit the
manufacturer's Web site.
ClearView Complete HIV 1/2
The
Clearview Complete HIV 1/2 is a
single-use rapid test that detects antibodies to HIV-1 and HIV-2 in fingerstick whole blood, venous whole blood, and serum or plasma
specimens. It is intended for use as a point-of-care test to aid in the
diagnosis of infection with HIV-1 or HIV-2. The shape of the device
resembles a syringe with a narrow sampler tip and the test strip
enclosed in the barrel. The single-use vial of buffer is stored in the
base of the barrel.
To conduct the test,
-
For fingerstick
whole blood: touch the blood drop with the test sampler tip until
the blood flows into and fills the tip.
-
For
venous whole blood, serum, or plasma: invert sampler and pipette 2.5
µL of specimen into sampler tip.
- Firmly press the sampler tip into the buffer vial through the foil
cover until sampler and buffer vial snap together.
- Wait
15 minutes, keeping the sampler tip/buffer vial mechanism upright in
the cardboard rack supplied with the kits.
The test result is
read directly from the device.
-
Read the test results after 15 to 20 minutes. Reactive test results
may be observed and read earlier than 15 minutes. To verify a
nonreactive test result, wait the entire 15 minutes. Do not read
results after 20 minutes.
-
A
reactive test will show two pink/purple lines—1 in the test area and
1 in the control area. A test result with visible lines in both the
test and control areas, regardless of intensity, is considered
reactive, which means that HIV-1 and/or HIV-2 antibodies have been
detected in the specimen. The test result is interpreted as
preliminarily positive for HIV-1 and/or HIV-2 antibodies.
-
A
nonreactive test will have 1 pink/purple line in the control area,
but no line in the test area. A nonreactive test result means that
neither HIV-1 nor HIV-2 antibodies were detected in the specimen and
the test result is interpreted as negative for both antibodies.
-
The test is invalid if there is no pink-purple line in the control
area. Similarly, a test is invalid if any lines appear outside the
control area or the test area. An invalid test cannot be
interpreted. An invalid test must be repeated with a new device.
Shelf Life of Kits:
24 months from the date of manufacture if stored at room temperature
For more information on the Clearview Complete HIV 1/2, see the test
kit
package insert
or
visit the
manufacturer's Web site.
Interpretation of Rapid HIV Test Results
The results of rapid HIV tests are interpreted the same way as the results
of other HIV screening tests.
- A
nonreactive result from a single test is considered negative. However, if
the person whose test result is negative may have been exposed to HIV within
the past 3 months, it may be too early for the test to detect HIV
antibodies. A repeat test at a later time is recommended.
-
A
reactive result from a rapid test is considered a preliminary positive
result. The test does not have to be repeated before the result is reported
as "preliminary positive." It must be followed up with another type of
test a Western blot, an immunofluorescence assay, or an RNA test to confirm
the result. The person is considered HIV-positive only if the confirmatory
test result is positive. A small proportion of specimens produce
indeterminate results in the confirmatory test. If this happens, the test
should be repeated after 1 month.
Special Note: Specimens from HIV-infected persons receiving highly active
antiretroviral therapy may produce false-negative results on rapid
tests.
For more information see CDC’s
Revised
Counseling, Testing, and Referral Guidelines.
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