Description

Rapid immunochromatographic test for the qualitative detection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) nucleocapsid protein antigen in human nasopharyngeal swab samples as an aid in rapid diagnosis of Coronavirus (Covid-19) infection.

 

PRINCIPLE

The test is performed by applying the extracted sample to the sample well (S) of the cassette and observing the formation of colored lines.
Nucleocapsid protein antigen to SARS-CoV-2 are detected by utilizing highly sensitive monoclonal antibodies.
The sample migrates by capillary effect along the membrane. If present in the sample, SARS-CoV-2 antigen react with monoclonal antibody conjugated colloid-gold particles and are captured by secondary monoclonal antibodies immobilized in the Test (T) region. A colored line will form in the Test (T) region. The presence of this colored line indicates a positive result, while its absence indicates a negative result.
As a procedure control a coloured line has to appear in the Control (C) region confirming that sufficient sample has been absorbed.

 

COMPOSITION
Individually packed test cassette, desiccant, extraction buffer Sterile swab, extraction tube, dropper tip, tube holder

 

STORAGE AND STABILITY
When stored in the sealed pouch at 2-30°C and protected from direct sunlight, moisture and heat the test cassette is stable until the indicated expiry date.

 

DO NOT FREEZE
Care should be taken to protect components of the kit from contamination.

 

SAMPLE COLLECTION AND PREPARATION
Note: Exclusively use nasopharyngeal swabs supplied in the kit. 1. Carefully insert the swab into the nostril of the patient until
reaching the surface of the posterior nasopharynx, which presents the most secretion under visual inspection.
2. Swab the surface of the posterior nasopharynx and rotate the swab several times.
3. Withdraw the swab from the nasal cavity.
Note: Do not use visually bloody or overly viscous samples.

Sample transport:
Sample is to be tested immediately after collection. If immediate testing is not possible place the swab in a dry, clean and unused plastic tube labelled with the patient information and cap tightly. Keep at room temperature (15° to 30°C) for not more than 1 hour.
If the sample cannot be tested within 1 hour a new sample has to be collected.
Note: Do not return nasopharyngeal swab into the packaging. Sample preparation:
1. Insert extraction tube into the tube holder and make sure that
the tube is standing firmly.
2. Hold Buffer bottle vertically and add 0.3 mL (appr. 10 drops)
into the extraction tube.
3. Insert the sample swab into the extraction tube containing the
extraction buffer.
4. Rotate the swab at least 6 times while pressing the head
against the inside and the bottom of the tube to release the antigen collected with the swab.
5. Leave the swab in the extraction tube for 1 minute.
6. Squeeze the tube with the fingertips to expel as much buffer
solution from the swab as possible and withdraw the swab. Discard swab in accordance with biohazard waste disposal protocol.
7. Fit a new dropper dip on the extraction tube.

 

PROCEDURE

Test cassette and sample must be at room temperature (15-30°C) prior to testing.
1. Remove test cassette from the foil pouch and place it on a flat
and clean surface.
For best results assay should be performed immediately.
2. Apply 4 drops of extracted solution (appr. 100 μL) to the sample well of the cassette.
3. Wait for the colored lines to appear and read the test result after 15 minutes.
IMPORTANT: Do not read the result after 20 minutes

 

INTERPRETATION OF RESULTS

Positive (+)
Two colored lines appear on the membrane. One line appears in the Control (C) and another line in the Test (T) region. The result is SARS-CoV-2 positive.
Note: Color intensity of the line appearing in the Test (T) region may vary depending on the concentration of SARS-CoV-2 antigen in the sample. Therefore, any shade of color in the Test (T) region is to be considered as a positive result.

Negative (-)
Only one colored line appears in the Control (C) region. No colored line appears in the Test (T) region.

Invalid
If a colored line is visible only in the Test (T) region or no colored line is visible at all the test is invalid and needs to be repeated with a new test cassette.
Note: Insufficient sample volume, incorrect procedure or expired test are most common reasons of invalid results.

 

QUALITY CONTROL

A colored line appearing in the Control (C) region is the internal procedural control confirming sufficient sample volume and correct test procedure. External controls are not included in the kit.
Nevertheless, use of external controls is recommended as part of Good Laboratory Practice to confirm and verify the test procedure and proper performance of the test. Positive and negative controls from a competent source are to be tested following the same procedure as applied for patient samples.

 

LIMITATIONS OF PROCEDURE

This test is for professional in vitro diagnostic use and is to be used for qualitative detection of nucleocapsid protein antigen to SARS-CoV-2 in human nasopharyngeal swab samples only.
No quantitative result or rate of increase in antigen concentration can be determined with this test.
The test is capable of detecting both viable and non-viable SARS-CoV-2. The performance depends on the antigen load and may not correlate with viral culture results performed on the same sample. Optimal assay performance requires strict adherence to the assay procedure. Deviations may lead to aberrant results.
If the test result is negative, but clinical symptoms persist, additional testing using other clinical methods is advised. A negative test result does not rule out the presence of SARS-CoV-2 antigens in the sample, as the antigen concentration may be below the minimum detection limit or the sample may have been collected or transported improperly.
A positive test result does not rule out co-infections with other pathogens.
A positive test result does not differentiate between SARS-CoV and SARS-CoV-2.
As for all diagnostic tests, results must be interpreted by a physician only after all clinical and laboratory findings have been evaluated.

 

PERFORMANCE

Detection limit (LOD):
The minimum detectable concentration of SARS-CoV-2 Ag is 1.15 x 102 TCID50/mL.

Sensitivity and specificity:
AMP Rapid Test SARS-CoV-2 Ag has been evaluated with clinical patient samples using a commercial molecular assay (RT PCR) as a reference method. Sensitivity, specificity and overall relative accuracy have been found to be as following:

Test sensitivity: 98% (95% CI: 90.0% – 99.8%)
Test specificity: 99,1% (95% CI: 96.6% – 100%)
Relative accuracy: 98.8% (95% CI: 91.8% – 99.9%)

Interferences
The following substances did not show any interference:
Human blood (EDTA), anti-viral drugs, antibiotics/anti-bacterial drugs, nasal sprays or nose drops, nasal corticosteroids.

Precision:

Intra-assay:
Negative, low positive (LOD) and high positive (4 x LOD) samples have been tested in 10 replicates each. Results have been detected correctly for >99% of the samples.

Inter-assay:
Negative, low positive (LOD) and high positive (4 x LOD) samples have been tested in 10 replicates each with AMP Rapid Test SARS-CoV-2 Ag from 3 different lots. Results have been detected correctly for >99% of the samples.

 

PRECAUTIONS

•  For professional in vitro diagnostic use only.
•  For external use only. Do not swallow.
•  Wear protective clothing: laboratory coats, gloves, eye protection.
•  Samples are potentially infectious and therefore have to be treated cautiously.
•  Avoid cross-contamination of samples by using a new sample collection container for each sample obtained.
•  The test and sampling accessories are intended for single use only.
•  Do not use other swabs than the ones supplied in the kit.
•  Do not use test cassette beyond expiry date.
•  Do not use test cassette in case that the pouch is punctured or not sealed correctly.
•  Keep out of the reach of children.
•  Humidity and temperature can affect the results.
•  Do not perform the test in a room with strong air flow, electric fan or strong air- conditioning.
•  Discard test cassette and sampling accessories after use according to the local regulations or laboratory rules for disposal of potentially infectious waste.
•  Extraction buffer contains 0.09% sodium azide as preservative. Flush with plenty of water in case of skin or eye contact. Sodium azide may react explosively, when in contact with lead or copper plumbing. Thus flush with plenty of water when disposing the solution through the sink.