For medical healthcare professional in vitro diagnostic use only
The COVID-19 IgG/IgM Cassette (Whole Blood/Serum/Plasma) is a rapid chromatographic immunoassay for the qualitative detection of IgG and IgM antibodies to SARS-CoV-2 in human whole blood, serum, or plasma. These antibodies may be detectable in primary and secondary SARS-CoV-2 infections. It is a rapid test that utilizes a combination of SARS-CoV-2 antigen-coated coloured particles for the detection of IgG and IgM antibodies to SARS-CoV-2 in human whole blood, serum, or plasma.
Who can run these tests?
The test should be only be used in accordance with the instructions supplied and results interpreted by or under the supervision of a Medical Healthcare Professional. The test is not for home use.
Who can buy these tests?
These tests are only available to customers who have a valid VAT (UK) or tax registration number (non-UK). Customers will have to submit a statement to confirm that the test will only be used in accordance with the instructions supplied and results interpreted by or under the supervision of a Medical Healthcare Professional. The test is not for home use.
What does it do?
The test detects the presence of specific antibodies related to Covid-19 in a sample of whole blood, serum or plasma. The test will show a positive result if it is able to detect the presence of 2 different antibodies: IgM and IgG.
If an individual is exposed to Covid-19, IgM is the first antibody to be produced in order to immediately help the human body to fight an infection. There is a delay of approximately 3 - 7 days* from onset of symptoms before the IgM antibody is produced to a high enough level whereby it is detectable by testing which means that a test could return a negative result (see Limitations section). However, once this detectable level has been reached, when a test is performed it will return a positive result.
The IgG antibody is produced after the initial phase of the infection to help protect against a repeat infection. This is detectable approximately 7 – 14 days* from the onset of symptoms. Once a detectable level of IgG has been reached, when a test is performed it will return a positive result.
If just IgM is positive then it is likely that the disease is active. If the result is IgG positive, or both IgG and IgM positive, that suggests that the subject may have evidence of some immunity. A positive IgG test does not guarantee immunity to Covid-19, but it is an indication of exposure. See figure 1 Approximate IgM and IgG antibody levels over time – Not actual data - for illustration purposes only
If the test is negative for both IgM and IgG antibodies this means that the patient could be in the latent phase of the infection or has not been infected.
*NOTE: The time frame for detection of both IgM and IgG antibodies can vary depending upon which publications are referenced and the cohort of patients that were tested.
Fig.1 - Approximate IgM and IgG antibody levels over time – Not actual data - for illustration purposes only
What is the difference between IgG and IgM antibodies?
Immunoglobulin G (IgG), the most abundant type of antibody, is found in all body fluids and protects against bacterial and viral infections. Therefore, this is the antibody that would be expected to found in the human body to help protect against repeat infection Covid-19.
Immunoglobulin M (IgM), which is found mainly in the blood and lymph fluid, is the first antibody to be made by the body to fight a new infection. Therefore, this is the antibody that would be expected to found in the human body to help fight an initial infection of Covid-19.
What is the difference between Primary SARS-CoV-2 infection and Secondary SARS-CoV-2 infection?
Primary SARS-CoV-2 infection is characterised by the presence of detectable IgM antibodies approximately 3-7 days after the onset of infection.
Secondary SARS-CoV-2 infection is characterized by the elevation of SARS-CoV-2 specific IgG. In the majority of the cases, this is accompanied by elevated levels of IgM.
What are the possible results?
IgG and IgM POSITIVE:* Three lines appear. One coloured line should be in the control line region (C), and two coloured lines should appear in IgG test line region and IgM test line region. The colour intensities of the lines do not have to match. The result is positive for IgG & IgM antibodies and is indicative of secondary SARS-CoV-2 Infection.
IgG POSITIVE:* Two lines appear. One coloured line should be in the control line region (C), and a coloured line appears in IgG test line region. The result is positive for SARS-CoV-2 virus specific-IgG and is probably indicative of secondary SARS-CoV-2 infection.
IgM POSITIVE:* Two lines appear. One coloured line should be in the control line region (C), and a coloured line appears in IgM test line region. The result is positive for SARS-CoV-2 virus specific-IgM antibodies and is indicative of primary SARS-CoV-2 infection.
*NOTE: The intensity of the colour in the IgG and/or IgM test line region(s) will vary depending on the concentration of SARS-CoV-2 antibodies in the specimen. Therefore, any shade of colour in the IgG and/or IgM test line region(s) should be considered positive.
NEGATIVE: One coloured line should be in the control line region (C). No line appears in IgG and IgM test line region(s).
INVALID: Control line fails to appear. Insufficient buffer volume or incorrect procedural techniques are the most likely reasons for control line failure. Review the procedure and repeat the procedure with a new test cassette. If the problem persists, discontinue using the test kit immediately and contact your local distributor.
Please note that individuals’ coexisting conditions need to be taken into consideration. People who have suppressed immunity due to illness or immunosuppressing drugs may not product antibodies in sufficient levels to be detected by this method.
What are the Limitations?
1. The COVID-19 IgG/IgM Cassette (Whole Blood/Serum/Plasma) is for in vitro diagnostic use only. The test should be used for the detection of SARS-CoV-2 antibodies in whole blood, serum or plasma specimens only. Neither the quantitative value nor the rate of increase in SARS-CoV-2 antibody concentration can be determined by this qualitative test.
2. The COVID-19 IgG/IgM Cassette (Whole Blood/Serum/Plasma) will only indicate the presence of SARS-CoV-2 antibodies in the specimen and should not be used as the sole criteria for the diagnosis of SARS-CoV-2.
3. In the early onset of fever, anti-SARS-COV-2 IgM concentrations may be below detectable levels. IgM may appear within 3-7 days after infection and then the concentration may decrease while IgG concentrations may increase. A positive result for IgM is indicative of primary SARS-COV-2 infection, however a negative result does not at any time preclude the possibility of SARS-COV-2 infection. Therefore IgM readings should be treated as advisory and should not be used as the sole criteria for the diagnosis of SARS-COV-2.
4. The continued presence or absence of antibodies cannot be used to determine the success or failure of therapy.
5. Results from immunosuppressed patients should be interpreted with caution.
6. As with all diagnostic tests, all results must be interpreted together with other clinical information available to the Medical Healthcare Professional.
7. If the test result is negative and clinical symptoms persist, additional testing using other clinical methods is recommended. A negative result does not at any time preclude the possibility of SARS-CoV-2 infection.
Is the COVID-19 IgG/IgM Cassette CE-marked?
Yes, on 11/03/20, the registration of the COVID-19 IgG/IgM Rapid Test Cassette with the German Competent Authority was finalised and received CE registration in the EU.
What samples are required to run the test?
The test works with either whole blood, serum, or plasma.
What is the testing time?
The test result should be read at 10 minutes. Do not interpret the result after 20 minutes.
Is there an order limit?
Kits are supplied in quantities of 25 tests.