Charting the Course to a Post-COVID World
Why quick, easy antibody tests will play an invaluable role in overcoming COVID-19
What is the AbC-19 Rapid Antibody Test?
The AbC-19 Rapid TestTM is an immunoassay designed to detect neutralizing IgG antibodies, enclosed in a compact, disposable plastic cassette.
- If IgG antibodies to SARS-CoV-2 are present in the sample, they form a complex with the antigen and gold labelled marker protein and are captured at the test line producing a pink-purple line. If no IgG antibodies to SARS-CoV-2 are present, no line appears.
- The test results are clearly visible in the result window after 20 minutes.
What does AbC-19 show: Neutralizing Antibodies
The AbC-19 Rapid Antibody Test was developed using the same antigen that the AstraZeneca vaccine is based on.
To protect against SARS-CoV-2, a patients’ antibodies need to be directed against the critical spike protein part of the virus. In fact, hospitalized patients that have antibodies mainly directed towards the ‘wrong’ part of the virus (the Nucleocapsid protein) were shown to be more likely to die.
The most efficient antibodies against the virus are so-called neutralizing
antibodies, which seem to be exclusively directed against the Spike protein.
The Oxford Vaccine triggers the body to produce trimeric spike protein neutralising antibodies and the UK-RTC AbC-19™ Rapid Test is specifically designed to detect those IgG antibodies which bind to the trimeric spike protein.
The trimeric spike protein was used as a template for many of the SARSCoV-2 vaccine candidates (AstraZeneca, Novavax, Moderna, Pfizer/BioNTech, GSK/Clover, CureVac and others) either as an encoding RNA molecule, presented on a virus-vector or as subunit protein-based vaccine concept.
Impressive Test Results
203 positive samples tested
450 negative samples tested
How can AbC-19 be used?
- Identify individual immunity
- Access immunity prior to entry
- Analyze community immunity
- Prioritize immune workforce to high-risk work areas
- Tool to open economy
- Vaccine trials
AbC-19 Measures Neutralizing Antibodies as far out as 20 weeks
Why is this important?
Verify that sustained neutralizing antibodies are present
- A small number of cases did not produce detectable antibodies secondary to infection. This number is estimated to be 1 in 16.1
- Antibodies decline in time. Antibodies have been detected as far out as 20 weeks. Testing is ongoing to understand how long antibodies will remain.
Measure Community Resistance
The UK government has not issued any formal update guidance following their announcement therefore currently the requirements remain as PCR tests to be completed.
We do not know and are waiting for this information to be provided to us so that we can ensure our service meets the requirements of the updated guidance.
We cannot confirm what the new guidance will be until the UK government formally updates their guidance.
Acon Laboratories, Inc is a large global diagnostics company based in the US with manufacturing facilities in the US, China and Mexico. The factory in China has been inspected and approved by the FDA.
It is very important for us to understand exactly where these tests are made and by whom to ensure consistency of quality and supply.
All medical devices have to follow a standard testing and certification process before they can be sold in the EU.
The Flowflex SARS-Cov-2 AntiGen Rapid Test Kits for Covid-19 have been through this process and are CE marked.
These test kits are fully approved for home test use.
The Medicines and Healthcare Products Regulatory Agency (MHRA) is the competent authority or regulatory body in the UK.
They do not approve tests on an individual basis but do allow manufacturers to put a CE mark on products that meet a target product profile set by the MHRA. This target product profile contains criteria that tests and test kits should meet.
The Acon Flowflex Rapid AntiGen test kit meets all of the target profile provided by the MHRA.
Public Health England is assessing tests in the UK at their laboratories in Porton Down. The Flowflex Test Kits has been submitted for review, but has yet to be called up for evaluation. When this occurs we will update our information accordingly.
The Flowflex tests detect moderate to high viral loads. Patients will have moderate to high viral loads about 3 days before symptoms start until between 7 and 10 days after symptoms start. In this window lateral flow tests, such as the Acon Flowflex tests are very effective.
A positive test should be repeated using a RT-PCR test for confirmation and entry into the national test and trace system. A negative test simply reflects a point in time, showing you do not have active COVID-19 today.
This is difficult to advise as regulatory advice differs. Some bodies advise testing twice a week, or perhaps every Monday in a standard five day week. Other guidance suggests testing every day.
Corona viruses are a large family of viruses which may cause illness in animals or humans. In humans, several corona viruses are known to cause respiratory infections ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). The most recently discovered coronavirus causes coronavirus disease COVID-19.
COVID-19 is the infectious disease caused by the most recently discovered coronavirus. This new virus and disease were unknown before. COVID-19 is now a pandemic affecting many countries globally.
The most common symptoms of COVID-19 are fever, dry cough, and tiredness. Some patients may have aches and pains, nasal congestion, sore throat, or diarrhea. These symptoms are usually mild and begin gradually. Some people become infected but only have very mild symptoms. Most people (about 80%) recover from the disease without needing hospital treatment. Around 1 out of every 5 people who gets COVID-19 becomes seriously ill and develops difficulty breathing. Older people, and those with underlying medical problems like high blood pressure, heart and lung problems, diabetes, or cancer, are at higher risk of developing serious illness. However, anyone can catch COVID-19 and become seriously ill. Even people with very mild symptoms of COVID-19 can transmit the virus. People of all ages who experience fever, cough and difficulty breathing should seek medical attention.
The SARS-CoV-2 Antigen Rapid Test is a lateral flow chromatographic immunoassay for the qualitative detection the nucleocapsid protein antigen from SARS-CoV-2 in nasal swab specimens directly from individuals who are suspected of COVID-19 by their healthcare provider within the first seven days of the onset of symptoms.
The SARS-CoV-2 Antigen Rapid Test is a qualitative membrane based chromatographic immunoassay for the qualitative detection of the nucleocapsid protein antigen from SARS-CoV-2 in human nasal swab specimens.
When specimens are processed and added to the test cassette, SARS-CoV-2 antigens, if present in the specimen, will react with the anti-SARS-CoV-2 antibody-coated particles, which have been pre-coated on the test strip. The mixture then migrates upward on the membrane by capillary action. The antigen-conjugate complexes migrate across the test strip to the reaction area and are captured by a line of antibody bound on the membrane. Test results are interpreted visually at 15 minutes based on the presence or absence of visually colored lines.
Results are for the identification of SARS-CoV-2 nucleocapsid antigen. This antigen is generally detectable in upper respiratory 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 agent detected may not be the definite cause of disease.
Negative results from patients more than seven days post symptom onset should be treated as presumptive and confirmed with a molecular assay, if necessary, for 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 infection control decisions. Negative results should be considered in the context of a patient’s recent exposures, history and the presence of clinical signs and symptoms consistent with COVID-19.
The known limitations of the SARS-CoV-2 Antigen Rapid Test are:
- The SARS-CoV-2 Antigen Rapid Test is for in vitro diagnostic use only. The test should be used for the detection of SARS-CoV-2 antigens in nasal swab specimens only. The intensity of the test line does not necessarily correlate to SARS-CoV-2 viral titer in the
- Specimens should be tested as quickly as possible after specimen collection and at most within the hour following collection.
- Use of viral transport media may result in decreased test
- A false-negative test may result if the level of antigen in a sample is below the detection limit of the test or if the sample was collected
- Test results should be correlated with other clinical data available to the
- A positive test result does not rule out co-infections with other
- A positive test result does not differentiate between SARS-CoV and SARS-CoV-2.
- A negative test result is not intended to rule out other viral or bacterial
- A negative result, from a patient with symptom onset beyond seven days, should be treated as presumptive and confirmed with a molecular assay, if necessary, for clinical
- If the differentiation of specific SARS viruses and strains is needed, additional testing is required.