CodaCare SARS-CoV-2 Antigen Test Kit
Intended Use
SARS-CoV-2 antigen Test Kit (LFIA) is a kind of Colloidal gold immunochromatographic technology reagent. It is intended to qualitatively detect the SARS-CoV-2 virus in people having symptoms within 7 days. It is intended to be used by a health professional or a laboratory professional. It uses human anterior nasal secretion, nasopharyngeal secretion, or throat secretion for testing. It is an aid for diagnosis, and results should not be used as the sole basis to diagnose or exclude SARS-CoV-2 infection. Coronavirus (CoV) belongs to the order Nidovirales under the Coronaviridae family with 4 genera: a, 3, and 8. The a and § genera are only pathogenic to mammals, while y and 8 genera mainly cause bird infections. CoV is mainly transmitted through direct contact with secretions or through aerosols and droplets. There is also evidence supporting fecal-oral transmission. 7 kinds of human coronaviruses (HCoV) that cause human respiratory diseases have been identified so far, including HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1, SARS-CoV, MERS-CoV and SARS-CoV-2. SARS-CoV-2 is one of the most contagious viral pathogens that cause human respiratory tract infections (RTI). Currently, patients infected by SARS-CoV-2 are the main source of infection. Asymptomatic infected people can also be an infectious source. Based on the current epidemiological investigation, the incubation period is 1 to 14 days, mostly 3 to 7 days. The clinical manifestations include fever, fatigue, cough and other symptoms, accompanied by dyspnea, which can rapidly develop into life-threatening severe pneumonia, respiratory failure, acute respiratory vesicle syndrome, septic shock, multiple organ failure, and severe metabolic acid-base imbalance.
Test Principle
Medomics SARS-CoV-2 antigen Test Kit (LFIA) detects the SARS-CoV-2 nucleocapsid antigens with colloidal gold immunochromatography using a double antibody sandwich assay. The test cassette contains (1) colloidal gold-labeled anti-SARS-CoV-2 Nucleocapsid Protein antibody, (2) one detection T line and one quality control C line fixed on a nitrocellulose membrane. T line is fixed with another anti-SARS-CoV-2 Nucleocapsid Protein antibody for detecting SARS-CoV-2. The quality control antibody is fixed on the C line. When the appropriate amount of test sample treated with lysis buffer is added to the sample well of the test cassette, the sample will move forward along the test strip via capillary action. If the sample contains SARS-CoV-2 nucleocapsid antigens and the concentration is higher than the limit of detection, the antigens will bind to the colloidal gold-labeled anti-SARS-CoV-2 Nucleocapsid Protein antibody. The immune complex will be captured by another anti-SARS-CoV-2 Nucleocapsid Protein antibody immobilized on the membrane, forming a red T line and indicating a positive result for SARS-CoV-2. If the sample contains no SARS-CoV-2 nucleocapsid antigens or the concentration is lower than the limit of detection, a negative result is displayed. Additionally, the test cassette also contains a quality control C line. Regardless of what nucleocapsid antigens are present the C line should appear to C indicate that the sample has been transported properly through the membrane. If the C line does not appear, it indicates that the test result is invalid and the sample is required to retest.
Mutation Virus Detection Compatibility Tips
SARS-CoV-2 antigen Test Kit(LFIA) detects Nucleocapsid protein, NOT spike protein of SARS-CoV-2.The mutations of SARS-CoV-2 variants B.1.1.7/B.1.351/B.1.1.28(P.1 /B.1.617.1/B.1.617.2/B.1.526/B.1.427/B.1.429 have be confirmed. All of those variants of Nucleocapsid proteins can be effectively detected by the SARS-CoV-2 antigen Test Kit(LFIA)
Test Kit Contents
- Type I test kit contains test cassettes, sterile swabs, sampling tubes, i vial containing lysis buffer, droppers and instructions for use.
- Type Il test kit contains test cassettes, sterile swabs, sampling tubes containing individual lysis buffer, droppers and instructions for use.
- Type IlI test kit contains test cassettes, sterile swabs, sampling tubes, buffer capsules containing individual lysis buffer, droppers and instructions for use.
- Test cassette contains test strip, cassette, and desiccant. The test strip contains colloidal gold-labeled anti-SARS-CoV-2 Nucleocapsid Protein antibody, nitrocellulose membrane (C line fixed with goat-anti-mouse gG polyclonal antibody, and T line fixed with another anti-SARS-CoV-2 Nucleocapsid Protein antibody).
Warnings and Precautions
- This test kit is used for in vitro diagnosis only.
- This test kit should be used by qualifed personnel with professional experience or proper training.
- This test kit should be used within 1 hour after opening the package, and samples from transport media will reduce sensitivity. The test cassette should not be used if
being wet or polluted. - Proper protection should be taken during testing to avoid splashing when adding sample.
- Dispose of all used or damaged test cassettes, sampling tubes, droppers, swabs, or other kit components as biohazardous materials.
- Negative results do not rule out SARS-CoV-2 infection, particularly in those who have been in contact with the virus.
- For the detection of SARS-CoV-2 and unexpected variants (mutant strains),the changes of epitopes caused by mutation sites of Nucleocapsid Protein may reduce the analytical sensitivity of the reagent and lead to false negative results.
Storage Instructions
The test kit should be stored away from direct sunlight at 2℃ to 30℃ with a shelf-life of 24 months. Do not freeze.
Sample Requirements
One test cassette can only be used to test one sample type. Sample types include nasopharyngeal secretion, throat secretion and nasal secretion.
- Anterior Nasal Sampling： Insert the swab into a nostril (2.5 cm). Be sure to collect any nasal drainage that may be present. Carefully rotate the swab in a circular path against the inside of the nostril at least 5 times. Using the same swab repeat the procedure in the other nostril.
- Nasopharyngeal secretion collection: Take out a swab from the pouch. Insert the swab into one of the patient’s nostrils until it reaches the posterior nasopharynx where there is the most secretion, gently rotate and rub the swab over the surface of the posterior nasopharynx for several times before taking it out.
- Throat secretion collection: Insert the whole swab completely into the throat from the mouth, centering on the throat wall and the reddened area of the palate tonsil, wipe both sides of the pharyngeal tonsil and posterior pharyngeal wall with moderate force. Try to avoid the tongue before taking it out.
Sample should be treated with lysis buffer provided in this kit as soon as possible after collection. If the sample cannot be processed immediately, it should be stored immediately in a dry, sterilized and strictly sealed plastic tube. It can be stored at 2℃-8℃ for 8 hours. Could be stored at -70℃ for 3 months.
Test Procedure
Do not open pouch until ready to use. Prep necessary materials: Timer | Tube rack for sampling tubes and specimens | Any necessary personal protective equipment. (Disposable working cap、Double chemical impermeable gloves、Isolation gowns 、Helmet with breathing apparatus、A pair of goggles、Rubber bottom shoes 、Waterproof protective foot covers)
- Sampling: vertically add 15 drops (approximately 350 μL) lysis buffer into the sampling tube from vial or open the seal of the sampling tube containing lysis buffer or twist and squeeze out all the lysis buffer into the sampling tube from capsule. Insert the swab (after collection) into the buffer. Rotate the swab against the inner tube wall 10 times and squeeze the swab from the outer tube wall 5 times to completely dissolve the sample in the buffer, then move the swab up until it is resting on the sample solution, squeeze the swab from the outer tube wall in order to leave the sample in the tube as much as possible. Remove and discard the swab, cover the tube with the dropper.
- Test procedures: Open the aluminum foil pouch, take out the test cassette and lay it on a clean flat surface, then mark the cassette with the patient ID or sample number and add 4 drops (approximately 100 μL) of processed sample extract into the sample well.
The result should be observed within 15-20 minutes. Results observed after 20 minutes are invalid.
Test Method Limitations
The accuracy of the test is dependent on the quality of the sample. Improper sampling or storage, using expired samples or repeated frozen-thawed samples can affect the test result. Test results can also be affected by temperature and humidity.
- Negative results may be caused by low concentration of SARS-CoV-2 antigens in the sample and therefore cannot completely rule out the possibility of infection.
- Some medication (e.g. high concentration of over-the-counter (OTC) or prescription medication such as nasal spray) in the collected samples may interfere with the test result. Please perform the test again if the result is in doubt.
- This product is only for qualitative testing and the specific concentration of each indicator must be measured using other quantitative methodologies.
- The results of this test are for clinical reference only and should not be the only basis for diagnosis. Results should be used in combination with clinical observations and other testing methods.
Display of Results/Expected Values
- Negative result: If only the quality control C line appears and the detection T line is not visible, the sample contains no SARS-CoV-2 antigens or the SARS-CoV-2 antigens concentration is lower than the limit of detection and the result is negative.
- Positive result: If both the quality control C line and the detection T line appear, then the SARS-CoV-2 antigens have been detected and the result is positive.
- Invalid result: If the C line does not appear, the result is invalid and a new test must be performed.
Note: The color intensity of the T line is related to the concentration of SARS-CoV-2 antigens contained in the sample, and the result should be determined by whether the T line is colored or not regardless of the color intensity.
External Positive and Negative Controls
Good laboratory practice suggests the use of positive and negative controls to ensure that test kits are working and that the test is correctly performed. Only one red-colored C line in the observation window can be seen while using a negative quality control swab. Both red colored C line and T line in the observation window can be seen while using a positive quality control swab. If the correct control results are not obtained, do not perform patient tests or report patient results. Contact your Local vendor or Medomics during normal business hours before testing patient specimens. Please refer to the Instructions For Use of Medomics SARS-CoV-2 antigen test kit (LFIA) External control swab kit for expected test results and other information. Ordering And Contact Information Reference Numbers: Type:IV: SARS-CoV-2 antigen test kit (LFIA) External control swab kit (1test /kit), Type:V: SARS-CoV-2 antigen test kit (LFIA) External control swab kit (10 tests /kit) If necessary, please contact your Local vendor or Jiangsu Medomics Medical Technology Co. Ltd Technical Services at (+86)025-58601060/ (+86)025-58601213 and email ( info@medomics-dx.com )
Product Performance
- High Dose Hook Effect No hook effect was observed with the SARS-CoV-2 virus up to a concentration of 1.0 x 105 TCIDso/mL.
- Limit of Detection – LoD Limit of Detection (LoD) studies determined the lowest detectable concentration of SARS-CoV-2 at which ≥95% of all (true positive) replicates test positive. Dilute the SARS-Cov-2 wild type with lysis buffer to a final concentration gradient of 5, 10, 50, 100, 200, 1000 TCID5o/mL.
| SARS-CoV-2 wild type tested (TCID50/mL) | Test Result |
| 1000 | 20/20 positive |
| 200 | 20/20 positive |
| 100 | 20/20 positive |
| 50 | 20/20 positive |
| 10 | 20/20 positive |
| 5 | 12/20 positive |
Verification of Variants
SARS-CoV-2 antigen Test Kit(LFIA) can detect the recombinant nucleocapsid antigens of SARS-CoV-2 variants listed below.
| WHO label | Alpha | Beta | Gamma | Kappa | Delta | Lota | Epsilon |
| Pango lineage | B.1.1.7 | B.1.351 | P.1 | B.1.617.1 | B.1.617.2 | B.1.526 | B.1.427/B.1.429 |
Cross Reactivity
Cross-reactivity and potential interference of Medomics SARS-CoV-2 antigen Test Kit (LFIA) were evaluated by testing commensal and pathogenic microorganisms diluted with nasal swabs as sample matrix in the absence or presence of heat inactivated SARS-CoV-2 virus. The listed items in the following table may be present in the clinical samples. Each of the bacterium, viruses, and yeast was tested in triplicate with no false positive results.
| Potential Cross-Reactant | Concentration Tested | Cross-Reactivity (Yes/No) |
| Human coronavirus 229E | 1.0 x 105 TCID50/mL | No |
| Human coronavirus OC43 | 1.0 x 105 TCID50/mL | No |
| Human coronavirus NL63 | 1.0 x 105 TCID50/mL | No |
| Human coronavirus HKU1 | 1.0 x 105 TCID50/mL | No |
| MERS-coronavirus | 1.0 x 105 TCID50/mL | No |
| SARS-coronavirus | 1.0 x 105 TCID50/mL | No |
| In uenza A H1N1 | 1.0 x 105 TCID50/mL | No |
| In uenza A H3N2 | 1.0 x 105 TCID50/mL | No |
| In uenza A H5N1 | 1.0 x 105 TCID50/mL | No |
| In uenza A H7N9 | 1.0 x 105 TCID50/mL | No |
| In uenza B Victoria | 1.0 x 105 TCID50/mL | No |
| In uenza B Yamagata | 1.0 x 105 TCID50/mL | No |
| Parain uenza virus Type 1 | 1.0 x 105 TCID50/mL | No |
| Respiratory syncytial virus | 1.0 x 105 TCID50/mL | No |
| Enterovirus CA16e | 1.0 x 105 TCID50/mL | No |
| Adenovirus | 1.0 x 105 TCID50/mL | No |
| Mycoplasma pneumoniae | 1.0 x 106 CFU/mL | No |
| Staphylococcus aureus | 1.0 x 106 CFU/mL | No |
| Staphylococcus epidermidis | 1.0 x 106 CFU/mL | No |
| Bordetella pertussis | 1.0 x 106 CFU/mL | No |
| Legionella pneumophila | 1.0 x 106 CFU/mL | No |
| Streptococcus pneumoniae | 1.0 x 106 CFU/mL | No |
| Haemophilus influenzae | 1.0 x 106 CFU/mL | No |
| Mycobacterium tuberculosis | 1.0 x 106 CFU/mL | No |
| Candida albicans | 1.0 x 106 CFU/mL | No |
Precision
Precision performance is determined by a precision test which uses a negative enterprise reference sample and two positive enterprise samples (weak positive and strong positive). The variability such as operator, days, assay runs, and dierent batches were covered in the test.
| Negative | Weak Positive | Strong Positive |
| 100% | 97.08% | 100% |
Interfering Substances Effect
The interfering substance tests conducted include but are not limited to the following interfering substances required by the WHO.
| Substance | Potential Interfering Substances | Concentration | Interference (Yes/No) | |
|
Endogenous Substance | Mucin | 2 % w/v | No | |
| Whole Blood | 5 % v/v | No | ||
| Human Anti-mouse Antibody(HAMA) | 200 IU/ml | No | ||
|
Exogenous Substance | Nasal spray or nasal drops | Phenylephrine hydrochloride | 15 % v/v | No |
| Oxymetazolin hydrochloride | 15 % v/v | No | ||
| Sodium chloride with preservatives | 4.44 mg/mL | No | ||
|
Nasal cortieosteroid | Beclomethasone | 4.79 ng/mL | No | |
| Dexamethasone | 0.8 mg/mL | No | ||
| Flunisolide | 0.61 µg/mL | No | ||
| Triamcinolone | 0.8 mg/mL | No | ||
| Budesonide | 0.5 mg/mL | No | ||
| Fluticasone Propionate | 5 % w/v | No | ||
| Throat Lozenge | Benzocaine | 0.13 mg/mL | No | |
| Antibiotic | Mupirocin | 0.25 % w/v | No | |
| Anti-Anti drugs | Tami u (Oseltamivir Phosphate) | 0.5 % w/v | No | |
| Antibacterial | Tobramycin | 24.03 µg/mL | No | |
| Biotin | Biotin | 1.2 µg/mL | No | |
Clinical Performance
The performance of Medomics SARS-CoV-2 antigen Test Kit(LFIA) was established with 363 Nasopharyngeal swabs collected from patients with COVID-19 symptoms within 7 days after onset of symptoms . Clinical samples were evaluated to be positive or negative using FDA EUA RT-PCR reference methods. Two copies of samples were collected from one patient. One copy was tested directly using Medomics SARS-CoV-2 antigen Test Kit(LFIA) and the other was tested by RT-PCR The results are summarized in the following:
Table 1: Medomics Results from Patients and PCR (Nasopharyngeal secretion)
| RT-PCR | |||
| Medomics Ag test | Positive | Negative | Total |
| Positive | 133 | 0 | 133 |
| Negative | 1 | 229 | 230 |
| Total | 134 | 229 | 363 |
| Sensitivity: 99.25% (95.91%-99.98%) PPV: 100% (97.26%-100%) Specificity: 100% (98.40%-100%) NPV: 99.57% (97.60%-99.99%) Accuracy: 99.72% (98.47%-99.99%) | |||
Table 2：Sensitivity by CT values (Nasopharyngeal secretion)
| CT value | Quantity of PCR Test Results | Quantity of Medomics Antigen Test Results | % Positive |
| Ct ≤25 | 89 | 89 | 100% |
| 25<Ct≤30 | 43 | 43 | 100% |
| 30<Ct≤33 | 2 | 1 | 50% |
| Total | 134 | 133 | 99.25% |
Table 3：Sensitivity by Days after symptom onset (Nasopharyngeal secretion)
| Days after symptom onset | Quantity of PCR Test Results | Quantity of Medomics Antigen Test Results | % Positive |
| 0 | 13 | 13 | 100% |
| 1 | 13 | 13 | 100% |
| 2 | 28 | 28 | 100% |
| 3 | 16 | 16 | 100% |
| 4 | 24 | 24 | 100% |
| 5 | 28 | 28 | 100% |
| 6 | 10 | 9 | 90% |
| 7 | 11 | 11 | 100% |
| Total Subjects | 143 | ||
The performance of Medomics SARS-CoV-2 antigen Test Kit(LFIA) was established with 264 Throat swabs collected from patients with COVID-19 symptoms within 7 days after onset of symptoms . Clinical samples were evaluated to be positive or negative using FDA EUA RT-PCR reference methods. Two copies of samples were collected from one patient. One copy was tested directly using Medomics SARS-CoV-2 antigen Test Kit(LFIA) and the other was tested by RT-PCR The results are summarized in the following:
Table 4: Medomics Results from Patients and PCR (Throat secretion)
| RT-PCR | |||
| Medomics COVID-19 Ag test | Positive | Negative | Total |
| Positive | 83 | 2 | 85 |
| Negative | 4 | 175 | 179 |
| Total | 87 | 177 | 264 |
| Sensitivity: 95.40% (88.64%-98.73%) PPV: 97.65% (91.76%-99.71%) Specificity: 98.87% (95.98%-99.86%) NPV: 97.77% (94.38%-99.39%) Accuracy: 97.73% (95.12%-99.16%) | |||
Table5: Sensitivity by CT values (Throat secretion)
| CT value | Quantity of PCR Test Results | Quantity of Medomics Antigen Test Results | % Positive |
| Ct ≤25 | 42 | 41 | 97.62% |
| 25<Ct≤30 | 43 | 41 | 95.35% |
| 30<Ct≤33 | 2 | 1 | 50% |
| Total | 87 | 83 | 95.40% |
Table 6: Sensitivity by Days after symptom onset (Throat secretion)
| Days after symptom onset | Quantity of PCR Test Results | Quantity of Medomics Antigen Test Results | % Positive |
| 0 | 8 | 7 | 87.5% |
| 1 | 7 | 7 | 100% |
| 2 | 18 | 18 | 100% |
| 3 | 14 | 14 | 100% |
| 4 | 18 | 16 | 88.89% |
| 5 | 21 | 20 | 95.24% |
| 6 | 4 | 4 | 100% |
| 7 | 7 | 7 | 100% |
| Total Subjects | 97 | ||
The performance of Medomics SARS-CoV-2 antigen Test Kit(LFIA) was established with 216 Anterior nasal swabs collected from patients with COVID-19 symptoms within 7 days after onset of symptoms . Clinical samples were evaluated to be positive or negative using FDA EUA RT-PCR reference methods. Two copies of samples were collected from one patient. One copy was tested directly using Medomics SARS-CoV-2 antigen Test Kit(LFIA) and the other was tested by RT-PCR The results are summarized in the following:
Table 7: Medomics Results from Patients and PCR (Anterior nasal secretion)
| RT-PCR | |||
| Medomics COVID-19 Ag test | Positive | Negative | Total |
| Positive | 107 | 1 | 108 |
| Negative | 5 | 103 | 108 |
| Total | 112 | 104 | 216 |
| Sensitivity: 95.54% (89.89%-98.53%) PPV: 99.07% (94.95%-99.98%) Specificity: 99.04% (94.76%-99.98%) NPV: 95.37% (89.53%-98.48%) Accuracy: 97.22% (94.05%-98.97%) | |||
Table8: Sensitivity by CT values (Anterior nasal secretion)
| CT value | Quantity of PCR Test Results | Quantity of Medomics Antigen Test Results | % Positive |
| Ct ≤25 | 64 | 63 | 98.44% |
| 25<Ct≤30 | 43 | 42 | 97.67% |
| 30<Ct≤33 | 5 | 2 | 40% |
| Total | 112 | 107 | 95.54% |
Table 9: Sensitivity by Days after symptom onset (Anterior nasal secretion)
| Days after symptom onset | Quantity of PCR Test Results | Quantity of Medomics Antigen Test Results | % Positive |
| 0 | 10 | 10 | 100% |
| 1 | 8 | 7 | 87.5% |
| 2 | 17 | 17 | 100% |
| 3 | 14 | 14 | 100% |
| 4 | 22 | 20 | 90.91% |
| 5 | 17 | 16 | 94.12% |
| 6 | 6 | 6 | 100% |
| 7 | 9 | 9 | 100% |
| Total Subjects | 103 | ||
[References]
- LY Wang, PR Chen, G W Zheng, et al. Research progress on novel coronavirus test methods. Modern Medicine and Clinic, 2020, 35(3): 411-416.
- K Tugba, W Ralph, L Hakho. Molecular and Immunological Diagnostic Tests of COVID-19: Current Status and Challenges. IScience, 2020, 23 (8): Doi: 10.1016/j.isci. 2020.101406
JENINNO SOLUTIONS PTY LTD UNIT 605, 12 ALBERT STREET, HAWTHORN EAST, VIC, 3123 info@jeninnosolutions.com.au Jiangsu Medomics Medical Technology Co.,Ltd. F3, BuildingC, No.3-1 XinjinhuRoad, Jiangbei New Area, Nanjing, Jiangsu, China. Tel: (+86)025-58601060/ (+86)025-58601213 Fax: 025-58601060 E-mail: info@medomics-dx.com
Documents / Resources
 | CodaCare SARS-CoV-2 Antigen Test Kit [pdf] Instruction Manual SARS-CoV-2 Antigen Test Kit, SARS-CoV-2, Antigen Test Kit, Test Kit |
