Description
Lateral flow immunochromatographic assay for the qualitative detection of SARS-CoV-2 nucleocapsid antigen in nasal and nasopharyngeal swab samples collected from individuals suspected by their healthcare providers of being potentially affected by COVID-19 within the first seven days of symptom onset.
The test can be used to analyze samples from asymptomatic individuals.
The SARS-CoV-2 Rapid Antigen Test does not distinguish between SARS-CoV and SARS-CoV-2. A positive result indicates the presence of SARS-CoV-2 nucleocapsid antigen. This antigen is generally detectable in upper respiratory tract samples during the acute phase of infection. Positive results indicate the presence of viral antigens, but clinical correlation with patient history and other diagnostic information is necessary to determine infection status. Positive results do not rule out bacterial infection or co-infection with other viruses. The detected agent may not be the definitive cause of the disease.
Negative results in patients with symptoms beyond seven days should be treated as presumptive and confirmed with a molecular test for proper patient management. Negative results do not rule out SARS-CoV-2 infection and should not be used as the sole basis for treatment or patient management decisions, including decisions regarding the clinical approach to infection. Negative results should be considered in the context of the patient's recent exposures, history, and the presence of clinical signs and symptoms consistent with COVID-19.
It is a qualitative membrane-based immunochromatographic assay for the qualitative detection of SARS-CoV-2 nucleocapsid antigen in human nasal and nasopharyngeal swab samples.
When extracted samples are processed and dispensed into the test cassette, SARS-CoV-2 antigens, if present in the sample, react with anti-SARS-CoV-2 antibody-coated particles, which are present on the test line (T). The mixture then migrates across the membrane by capillary action. The antigen-conjugate complexes migrate through the test strip to the reaction area and are captured by a line of antibodies bound on the membrane.
Test results are interpreted visually after 15-30 minutes based on the presence or absence of visible colored lines.
As an exclusive procedural control, a colored line always appears in the control line region (C), indicating that the correct volume of sample has been added and proper membrane wicking has occurred.
The test is intended for use by trained clinical laboratory personnel and qualified healthcare professionals at point-of-care settings. It is intended to be used as an aid in the diagnosis of SARS-CoV-2 infection.

Instructions for use
Sample collection and preparation:
The SARS-CoV-2 Rapid Antigen Test can be performed using nasopharyngeal swab samples.
The test should be performed immediately after sample collection, or at most within one hour (1) of sample collection, provided it is stored at room temperature (15-30 °C).
Refer to the Sample Collection Guide included in the kit for details on sample collection.

Test procedure:
Allow the sample and extraction buffer to reach room temperature (15-30 °C) before testing.
Use one extraction buffer tube for each sample to be tested and label each tube appropriately.
Remove the foil seal from the top of the extraction tube. Insert the swab into the tube and agitate for 30 seconds. Then rotate the swab at least 5 times while squeezing the sides of the tube. Be careful not to splash the contents out of the tube. Remove the swab by pressing the sides of the tube to extract liquid from the swab.
Securely attach the dropper tip to the extraction buffer tube containing the sample. Mix thoroughly by swirling or flicking the bottom of the tube.
Remove the test cassette from the foil pouch and use it as soon as possible. Place the test cassette on a clean, flat surface.
Add the processed sample to the corresponding well of the test cassette. Invert the extraction buffer tube with the dropper tip facing down, holding it vertically. Gently squeeze the tube, dispensing 4 drops of the treated sample into the sample well.
Wait for colored lines to appear. The result should be read after 15-30 minutes. Do not read the result after 30 minutes.

Interpretation of results:
NEGATIVE: Only one colored line appears in the control line region (C). No visible colored line appears in the test line region (T). This means no SARS-CoV-2 antigen was detected.

POSITIVE: Two distinct colored lines appear. One line in the control line region (C) and the other in the test line region (T). This means SARS-CoV-2 antigen was detected.
The intensity of the color of the test line (T) may vary depending on the level of SARS-CoV-2 antigen present in the sample. Therefore, any shade of color in the test line region (T) should be considered positive.

INVALID: No control line appears. Insufficient sample volume or incorrect test procedure are the most likely reasons for the absence of the control line. Review the procedure and repeat the test with a new test cassette. If the problem persists, discontinue use of the kit and contact your local distributor.

Warnings
For professional in vitro diagnostic use only. Do not use beyond the expiration date.
Do not eat, drink, or smoke in the area where samples or the kit are handled.
Do not use the test if the outer packaging is damaged.
Handle all samples as if they contain infectious agents. Observe established biohazard precautions during testing and follow standard procedures for proper sample disposal.
Wear protective clothing, such as lab coats, disposable gloves, masks, and eye protection when testing samples.
Used tests must be disposed of in accordance with local regulations. Used tests must be considered potentially infected and disposed of in accordance with local regulations.
Humidity and temperature can adversely affect results.
Read the insert carefully before performing the test. Failure to follow the instructions specified in the insert may not yield accurate test results.
The test line for a sample with a high viral load may become visible within 15 minutes, or as soon as the sample passes the test line area. The test line for a sample with a low viral load becomes visible after 30 minutes.
Samples must be tested as quickly as possible after sample collection and at most within one hour after collection.
The use of conservation and stabilization media for sample transport may result in a reduction of test sensitivity.
A false negative test may be obtained if the antigen concentration in a sample is below the detection limit of the test or if the sample was collected incorrectly.
Test results must be correlated with other clinical data available to the physician.
A positive test result does not rule out co-infections with other pathogens. A positive test result does not distinguish between SARS-CoV and SARS-CoV-2.
A negative test result is not intended to rule out other viral or bacterial infections. A negative result, in a patient with symptom onset beyond seven days, should be treated as presumptive and confirmed with a molecular test, based on which clinical treatment should be established (if differentiation of specific SARS viruses and strains is needed, further testing should be performed).

Storage
Store at a temperature between 2-30 °C. Do not freeze.
The test is stable until the expiration date printed on the sealed outer packaging. The test must remain in the sealed pouch until use. Do not use beyond the expiration date.
Shelf life of unopened packaging: 24 months.

Format
Kit of 25 pieces. Contains:
- Test cassettes;
- Positive control swab;
- Disposable swabs (nasopharyngeal);
- Sample collection guide;
- Extraction buffer tubes;
- Negative control swab;
- Package insert.

Bibliography
1. Shuo Su, Gary Wong, Weifeng Shi, et al. Epidemiology, Genetic recombination, and pathogenesis of coronaviruses. Trends in Microbiology, June 2016, vol. 24, No. 6: 490-502
2. Susan R. Weiss, Julian L. Leibowitz, Coronavirus Pathogenesis, Advances in Virus Research, Volume 81: 85-164

Code L031-11815