Wholesale Antibody Tests | For Hospitals and Public Health

Antibody tests

One of the two types of rapid tests we sell at Nobraa is the antibody test. The antibody test, also called covid antibody test or serological test is invented to test if someone has had corona or is finally recovering from the virus. The antibody test is usually a blood test since antibodies are plentiful in the bloodstream. Antibodies can also be found in saliva, and a variety of salivary antibody assays are now available. These tests, on the other hand, may not be as accurate as blood testing. A blood sample is taken and sent to a lab to be tested for COVID-19 antibodies. The viral COVID-19 test, on the other hand, requires swabbing the inside of your nose and back of your throat to collect saliva and respiratory fluids in order to look for evidence of the virus itself.

What are Antibodies and Antibody tests?

After you have had a virus, your body will make antibodies for that specific virus. This is also the case with the Covid-19 virus. After you have been infected with the coronavirus, your immune system starts making substances to recognize the virus so they can fight against it the next time you get infected. These substances are the antibodies!

These antibodies will work against the virus the next time you are infected. Because the antibodies recognize the virus and start binding to the outside of the virus, they ensure that the virus can no longer enter other body cells. This stops the infection and your body can start producing more antibodies and destroy the virus.

An antibody test (also called a serology test) looks for antibodies in the blood. These are proteins that your immune system makes, usually after you're exposed to germs like viruses or bacteria or after you get a vaccine. Antibodies work to fight illness.

A COVID-19 antibody test looks for antibodies to SARS-CoV-2, the virus that causes COVID-19. If you test positive for these antibodies, it could mean that you already had COVID-19. If you’ve received the COVID-19 vaccine, it’s not yet known how this will affect the antibody test results.

Most people don’t need this test. Antibody testing is mostly used to help track the virus, and the test is not commonly done in Alberta. These test results still mean that everyone must keep following all public health measures to help stop the spread of COVID-19.

Why has the Antibody Covid Test been done?

This test can be used to diagnose a past infection with the virus that causes COVID-19. This test is not useful for finding out if you have COVID-19 now because it can take weeks for your body to make enough antibodies to show up on the test. Another testing that directly detects the virus, like the COVID-19 viral test (or nucleic acid test) is used to diagnose new COVID-19 infections.

Antibody testing is useful because:

A positive result shows that you've already had COVID-19. But even if you have the antibody against SARS-CoV-2, you’re not considered immune to the virus. Keep doing things like wearing a mask, washing your hands often, and practicing physical distancing.
It could show who hasn't had COVID-19. Even though a negative result shows you haven’t been infected, you’re still at risk. Keep taking steps to protect yourself from the virus.
It helps experts who are tracking COVID-19 learn more about the virus and how it spreads.

Nobraa offers COVID-19 (SARS-CoV-2) antibody testing to support the determination of whether an individual has had the COVID-19 virus in the past.

Antibody tests, also known as serology tests, detect antibodies in the blood. Antibodies are generated by the body as part of an immune response. Immunoglobulin G (IgG) is the most common type of antibody in your blood and other body fluids. An individual with COVID-19 antibodies likely has been infected with COVID-19 in the past. Antibodies can usually be detected in a person’s blood 2-3 weeks after symptoms begin.

By contrast, standard nasal swab testing (molecular PCR tests) is the first line of testing to determine if a person has an active COVID-19 infection. COVID-19 antibody testing measures the number of COVID-19 antibodies in a blood sample.

It was first used to find out whether a person had already had the virus. This helped us understand how the disease was spreading. They can now also tell us if someone has had a coronavirus vaccination. Antibody tests are different from antigen (swab) tests which see if you currently have the virus.

The body's immune system produces antibodies when it detects harmful substances, called antigens. When a person has COVID-19 (the antigen) it produces COVID-19 antibodies. Antibodies recognize and latch onto antigens to remove them from the body. The antibodies produced for each antigen are unique, hence the term COVID-19 antibodies.

How does the antibody test work?

The antibody test works as follows. Using a small blood sample from the finger, the blood is tested for IgG and IgM antibodies. IgM is the antibodies that are often produced at the beginning of the infection and IgG when larger quantities are being produced or when the body gets in contact with the virus for the second time. If these antibodies are found in the blood, the test will therefore indicate that you/your patient has had corona.

In the case of a long-term infection, the test can sometimes also indicate that a person has corona at that moment. However, this is not guaranteed and the test is not suitable for this because the body often only produces antibodies two or three weeks after the infection. Would you like to test at home whether you have corona? Then, instead of the antibody test, you should buy an antigen self-test.

What are antibody tests used for?

As indicated above, antibody tests are not suitable to use as a self-test to check whether you have corona. On the contrary, professionals should only carry antibody tests, which is why only companies or healthcare professionals can order them.

The serological tests are currently mainly used by laboratories for population screening. The RIVM gives insight into people's resistance to the coronavirus by administering these tests to the Dutch population. The tests are also used in hospitals in exceptional situations, for example, if someone remains infected for longer than average or suddenly develops serious symptoms when already being infected.

Since December 2020 we have been vaccinating people across Wales. Vaccination produces antibodies in the blood that can detect and neutralize the antigen.

Before December 2020 COVID antibodies were only found in people with the disease.

Since December 2020 the presence of antibodies in a person’s blood sample could either be due to:

previous infection
vaccination or both

Antibody tests are now able to detect two different types of antibodies:

‘n’ antibodies (nucleocapsid) which appear after an infection
‘s’ antibodies (spike antibodies) which appear after an infection or vaccination

COVID-19 antibody testing measures the number of COVID-19 antibodies present in a blood sample.

They were first used to find out whether a person had already had the virus and helped us understand how the disease was spreading. They can now also tell us if someone has had a coronavirus vaccination.

Antibody tests are different from antigen (swab) tests which see if you currently have the virus.

An antibody is a protein produced by the body's immune system when it detects harmful substances, called antigens. When a person is infected by COVID-19 (the antigen) it produces COVID-19 antibodies. Antibodies recognize and latch onto antigens in order to remove them from the body. The antibodies produced for each antigen are unique, hence the term COVID-19 antibodies.

Since December 2020 we have been vaccinating people across Wales. Vaccination works in a number of ways but one of the things it does is to produce antibodies in the blood which are ready to detect and neutralize the antigen if it appears.

Before December 2020 COVID antibodies were only found in people who had been infected with the disease. Since December 2020 the presence of antibodies in a person’s blood sample could either be due to a previous infection or vaccination or both.

Antibody tests are now able to detect two different types of antibodies - n antibodies (nucleocapsid) which appear after an infection and s antibodies (spike antibodies) which appear after an infection or vaccination.

The value of antibody testing

Antibody testing tells us how many people have had the infection and how far and wide the virus has spread. It also reflects how many people have had the vaccination.

There is currently not enough evidence on how well COVID-19 antibodies are at:

fighting the virus
protecting you from getting it again
stopping transmission to others

We also don’t know how long antibodies from the infection will last. As scientific evidence and research improve this should provide answers to these questions.

Antibody testing tells us how many people have had the infection and how far and wide the virus has spread. It also reflects how many people have had the vaccination.

We don't know enough yet about how effective antibodies from the infection are at getting rid of the virus. Whether they will protect you from getting it again, or whether you can’t pass the virus on to others. We also don’t know how long antibodies from the infection will last. As the scientific evidence and research grow, we hope to have the answers to these questions.

Is the antibody test reliable?

The certified antibody tests are very reliable. At Nobraa we only sell the Lepus Medical Serological Rapid Test, which has the required CE mark and meets the requirements of the EU IVD (In-Vitro Diagnostics) Directive (98/79/EC). This test is therefore very reliable, specifically for 99.3%!

There are only a few situations in which the antibody test is not suitable and therefore the result may not be correct. If you just recovered from the virus or if you are still infected, it is possible that the body has not made any antibodies yet. It is therefore not a suitable test for testing whether you have the coronavirus at that moment. It is also possible that people who have not been ill from the virus or who have only had slight symptoms have not made enough antibodies to show this in an antibody test.

The COVID-19 IgG Antibody (Serology) Test is for people who feel well and want to know if they recently had COVID-19. This blood test does not require fasting or dietary restrictions.

This blood test is designed to detect antibodies (immunoglobulins, IgG and IgM) against the coronavirus that causes the disease called COVID-19. Antibodies are proteins produced by the immune system in response to an infection and are specific to that particular infection. They are found in the liquid part of blood specimens, which is called serum or plasma, depending on the presence of clotting factors. IgM and IgG may either be ordered together or separately.

Having an antibody test is helpful if:

your health care provider believes you may have been exposed to the coronavirus which causes COVID19 based on your current or previous signs and symptoms (e.g., fever, cough, difficulty breathing);
you live in or have recently traveled to a place where transmission of COVID-19 is known to occur;
you have been in close contact with an individual suspected of or confirmed to have COVID-19; or
you have recovered from COVID-19.

Antibody Test for IgG

This test detects IgG antibodies that develop in most patients within seven to 10 days after symptoms of COVID-19 begin. IgG antibodies remain in the blood after an infection has passed. These antibodies indicate that you may have had COVID-19 in the recent past and have developed antibodies that may protect you from future infection. It is unknown at this point how much protection antibodies might provide against reinfection.

IgM is usually the first antibody produced by the immune system when a virus attacks. A positive IgM test indicates that you may have been infected and that your immune system has started responding to the virus. When IgM is detected, you may still be infected, or you may have recently recovered from a COVID-19 infection.

When is antibody testing done and why is it important?

Antibody testing, also known as serology testing, is usually done after full recovery from COVID-19. Eligibility may vary, depending on the availability of tests. A health care professional takes a blood sample, usually by a finger prick or by drawing blood from a vein in the arm. Then the sample is tested to determine whether you've developed antibodies against the virus. The immune system produces these antibodies — proteins that are critical for fighting and clearing out the virus.

If test results show that you have antibodies, it indicates that you were likely infected with COVID-19 at some time in the past. It may also mean that you have some immunity. But there's a lack of evidence on whether having antibodies means you're protected against reinfection with COVID-19. The level of immunity and how long immunity lasts are not yet known. Ongoing studies will eventually reveal more data on this.

Importance of the test

The timing and type of antibody test affect accuracy. If you have tested too early in the course of infection, when the immune response is still building up in your body, the test may not detect antibodies. So, antibody testing is not recommended until at least 14 days after the onset of symptoms. The U.S. Food and Drug Administration (FDA) authorized specific antibody tests, but tests with questionable accuracy are still on the market.

Another benefit of accurate antibody testing is that people who've recovered from COVID-19 may be eligible to donate plasma, a part of their blood. This plasma could be used to treat others with severe diseases and boost the ability to fight the virus. Doctors call this convalescent plasma.

False-negative results can sometimes occur. This can happen if you get an antibody test too soon after being exposed or vaccinated and your body has not yet made enough antibodies to be detected by the test. Additionally, some individuals, such as those with weakened immune systems due to a medical condition or certain medications, may not develop detectable levels of antibodies after exposure or vaccination. False-positive results can also occur. This can happen if the test detects antibodies from other coronaviruses, you may have been exposed to, like the virus that causes the common cold.

If you are concerned about your results, it is important to follow up with a healthcare provider, who can evaluate your medical history. If you have been previously diagnosed or suspect you’ve been exposed to COVID-19, you should wait to get an antibody test until it has been at least 10 days after your symptoms started or after testing positive, you have not had a fever or felt feverish for 24 hours without taking fever-reducing medication, and any symptoms have improved. Current research shows that it may be best to get antibody testing 3 to 4 weeks after symptom onset or known exposure to COVID-19 to lower the chance of receiving a false-positive or false-negative result. Talk to your healthcare provider for more information about whether or not you should get tested.

When should I get a COVID-19 antibody test?

COVID-19 antibody tests are typically only used in specific circumstances. Most often, the test is prescribed when you have symptoms that could be related to COVID-19, but the infection is believed to have occurred several weeks or months earlier. In these cases, you may have already tested negative for active infection with SARS-CoV-2.

You may also get a serology test if you are taking part in a research study. In this situation, you will be advised about the details of the study’s purposes and procedures prior to testing.

Antibody tests cannot be used to show if you are immune to COVID-19. They also cannot prove whether vaccination was effective. Not enough is known about the relationship between antibody levels and immunity, and for this reason, the CDC advises against using antibody tests in these contexts.

When serology testing is conducted, it is important to consider the time it takes for the immune system to produce antibodies. It often takes several weeks for antibodies to become detectable, so an antibody test too soon after infection may not be accurate. In addition, although antibodies have been detected for around eight months after infection in some people, they may last for a shorter period of time in others.

COVID-19 Antibody Test Results

Receiving test results

Many antibody tests are point-of-care tests, which means that your test sample can be analyzed on-site and without sending it to a laboratory. These are often rapid tests with results available in 30 minutes or less. If the test sample is sent to a laboratory, you should receive results within a few business days.

You may get your test results from your doctor or another health care provider who conducts a rapid point-of-care test. A test report may also be sent by mail or made available to you electronically.

Interpreting test results

Your test result is typically listed as either positive or negative. Positive means that antibodies to SARS-CoV-2 were found in your blood. Current tests do not usually provide a detailed list of the precise numbers of specific antibodies detected.

In general, a positive test result reflects a previous infection with SARS-CoV-2, but it is possible for a person who has never had COVID-19 to have a positive test. This is known as a false positive, and it can occur if antibodies to another type of coronavirus were detected by the test as antibodies to SARS-CoV-2.

Similarly, a negative test result does not assure that you have never had COVID-19. It is believed that antibodies wane over time, and people who had mild or asymptomatic cases of COVID-19 may develop fewer antibodies. Additionally, some individuals do not produce these types of antibodies after infection, but still, produce other immune cells in response to infection. Therefore a negative antibody test should not be used to rule out immunity.

It is important to talk with your doctor about how to interpret the result of your antibody test. Because of the possibility of a false positive or false negative test, your doctor considers your results within the context of your situation including your symptoms and the likelihood that you were previously exposed to SARS-CoV-2.

In general, serological tests are blood-based tests that are used to determine whether people have been infected by particular pathogens. The immune system recognizes pathogens as foreign and mounts a protective response involving the development of antibodies. The presence or absence of SARS-CoV-2 specific antibodies can determine whether a person has been infected by the virus. The antibodies tested are IgM and IgG antibodies.

Early response in the nose may predict severe COVID-19

How cells in the nose respond to the coronavirus might someday be used to predict how sick a person will become with COVID-19, according to a new study. Researchers analyzed immune activity in cells taken from patients' nasal swabs at the time of COVID-19 diagnosis, comparing those who became only mildly ill to those who eventually required mechanical support with breathing. "When our cells in the nose meet a virus-like SARS-CoV-2 ... the ways that they sound the alarm to generate a rapid antiviral response vary greatly across people," said Jose Ordovas-Montanes of Harvard University.

"Individuals who went on to develop severe COVID-19 had a significantly muted alarm system," regardless of how much virus was present, Ordovas-Montanes said. Lack of a strong initial antiviral response might allow the virus to spread more rapidly, increasing the chances that it can move from the upper to lower airways, Ordovas-Montanes and colleagues suggest in a report published in the journal Cell bit.ly/3iffJLa. "If further studies support our findings, we could use the same nasal swabs we use to diagnose COVID-19 to identity potentially severe cases before severe disease develops, creating an opportunity for effective early intervention," study co-author Carly Ziegler, a graduate student at Harvard and the Massachusetts Institute of Technology, said in a press statement.

Is the antibody test better than the viral test?

These are two different tests, which provide complementary information, so it’s best to go with what your doctor recommends. The antibody test can be useful to tell if a person has been infected with the coronavirus in the past, even if they did not have any symptoms. Certain kinds of antibody tests may provide more information about your risk for re-infection. However, this question of whether people who have SARS-CoV-2 antibodies are protected against future infection with the virus is still a very active area of investigation.

Should I get an antibody test?

Talk to your doctor, who can help you decide if getting an antibody test is appropriate. Doctors might recommend an antibody test if you develop symptoms consistent with COVID-19 but your viral test is negative, or if you had symptoms of COVID-19 earlier this year but didn’t get tested for it. If your antibody test is positive, you might be able to participate in research studies working to understand the effects of the coronavirus on people’s health. Also, if you have the antibodies in your blood, you might be able to donate plasma to help another person who is very sick with COVID-19.

Understanding Your Serum Antibody (Blood Test) Result

Quest Labs will report your results as:

Positive: You produced the COVID-19 IgG antibody and have a high likelihood of prior infection. Some patients with past infections may not have experienced any symptoms. It is unclear at this time if a positive IgG infers immunity against future COVID-19 infection. Please continue with universal precautions: social distancing, hand washing, and when applicable PPE such as masks or gloves.

Negative: You tested negative for COVID-19 IgG antibody. This means you have not been infected with COVID-19. Please note, it may take 14-21 days to produce detectable levels of IgG following infection. If you had symptoms consistent with COVID-19 within the past 3 weeks and tested negative, repeat testing in 1-2 weeks may yield a positive result.

Equivocal: Your test results could not be interpreted as Positive or Negative. The most common reasons for equivocal results are the presence of immune response but unclear if against the infection being tested for (COVID-19 in this case) or similar infections (the common cold is a type of coronavirus). If indicated, a repeat test may yield more reliable results.

The Difference Between Tests for COVID-19 (Coronavirus)

COVID-19 (Coronavirus) Molecular (Swab) Test

This test uses a long swab to collect material, including physical pieces of coronavirus, from the back of the nose where it meets the throat. A positive result indicates that viral genetic material is present, but it does not indicate that bacterial or other infections also are present. A negative result indicates that the SARS-CoV2 virus that causes the COVID-19 disease was not found. It is possible to have a very low level of the virus in the body with a negative test result.

This test is needed to identify the presence of the SARS-CoV-2 virus that causes the COVID-19 disease.

Nucleocapsid Protein IgG Antibody Test

This is a blood test. It is designed to detect IgG antibodies specific for nucleocapsid protein of the coronavirus that causes the disease called COVID-19. Antibodies are proteins produced by the immune system in response to an infection and are specific to that particular infection. They are found in the liquid part of blood specimens, which is called serum or plasma. Nucleocapsid Protein and IgG Spike Protein IgG antibody tests may either be ordered together or separately.

Having the nucleocapsid protein antibody test is helpful if:

Your health care provider believes you may have been exposed to the coronavirus which causes COVID-19 based on your current or previous signs and symptoms (e.g., fever, cough, difficulty breathing).
You live in or have recently traveled to a place where transmission of COVID-19 is known to occur.
You have been in close contact with an individual suspected of or confirmed to have COVID-19.
You have recovered from COVID-19.

What if the antibody test is positive?

A positive test means you may have been exposed to SARS-CoV2, the virus causing COVID-19. Some tests may detect other common viruses or a positive may simply be a “false positive”. If you have had an illness with symptoms similar to COVID-19 symptoms, a positive test is more likely to be correct.

If I have antibodies to SARS-CoV-2, does that mean that I will not get COVID-19 in the future? We do not yet know which antibodies protect against COVID-19. A positive test does not necessarily mean that you have any protection against future infection.

Does everyone who is sick with COVID-19 make antibodies to the virus causing COVID-19? No. Not all people make antibodies to the virus. A small number of people do not make antibodies. Some of these people have weaker immune systems, some have normal immune systems, and had very mild symptoms of COVID-19.

Are all tests for antibodies the same?

No. There is a wider range of tests currently being offered. Different tests are not equally good at detecting antibodies. The FDA has been issuing Emergency Use Authorization to test companies. This means the usual rigorous testing by FDA has not been done. Companies and laboratories are evaluating the tests prior to offering them to patients. There is wide variability.

Is there any value in getting this test?

Talk with your provider to help answer this question. Currently, there is limited value in getting the test since we don’t know how accurate it is in telling you what most people want to know: Am I protected from COVID-19? If you get the test and it shows no antibodies, then it is likely you are NOT protected, and it is recommended to continue to follow physical distancing guidelines.

If you get the test and it does show antibodies, it is still not known if you are protected from COVID-19 and it is recommended you follow the same physical distancing guidelines. If you have had prior symptoms of COVID-19 infection > 21 days ago, the test may be more accurate for you. If you have NOT had symptoms of COVID-19 infection, a test showing you have antibodies may be inaccurate.

Buy Antibody tests online

At Nobraa we like to operate as a medical wholesaler. We, therefore, sell all medical articles, including antibody tests, in large quantities. So, are you a healthcare professional or company that needs dozens or maybe even hundreds of antibody tests?

Then you have come to the right place! The Lepu Medical Serological Rapid Tests are sold per box of 20 and we make sure that we always have them in stock. So you will never be short of medical supplies.

Antibody tests | COVID-19 test kits in bulk