FDA and the CDC Destroy Antibody Testing and Immunity

If you want more evidence that unproven theoretical antibody measurements are absolutely useless, it’s always fun to go directly to the accepted mainstream sources themselves. Many times, you can find very revealing nuggets of information buried within their releases. This information tends to contradict the claims they make publicly. Case in point, the claim that vaccine induced (artificial) immunity is better than natural immunity. If you go through both the FDA and CDC, you will see that this is a claim that even they themselves can not back up with evidence. Along with this, there are many other admittances they make in regards to not knowing what the antibody results actually mean nor whether there is any immunity to be gained at all. There are also some fun concessions in regards to the inaccuracies of the antibody tests themselves.

Let’s start with the FDA. This was apparently an updated response from December 2020:

Serology/Antibody Tests: FAQs on Testing for SARS-CoV-2

Q: If antibody tests are not used for diagnosis or exclusion of COVID-19 infection, what is their purpose? (Updated 12/2/20)

“A: Serology (antibody) tests may detect different types of antibodies. The most common are IgM and IgG. High quality serological tests can help us understand whether a person or population of people have developed antibodies indicative of an adaptive immune response to COVID-19.

Because a serology test can yield a negative test result even in infected patients (for example, if antibodies have not yet developed in response to the virus) or may generate false positive results (for example, if antibodies to a coronavirus type other than the current pandemic novel strain is present), antibody tests should not be used in the immediate (or acute) diagnosis of a patient where COVID-19 infection is suspected. That is, these tests should not be used to diagnose acute COVID-19 infection. Using this type of test on many patients may help the medical community better understand how the adaptive immune response against the SARS-CoV-2 virus develops in patients over time and how many people may have been infected. While there is a lot of uncertainty with this new virus, it is also possible that, over time, broad use of antibody tests and clinical follow-up will provide the medical community with more information on whether or not, and how long, a person who has recovered from the virus is at lower risk of infection if they are exposed to the virus again.

Positive results from appropriately validated serology tests that are designed to be very specific to the SARS-CoV-2 virus can indicate whether a patient has had recent or prior COVID-19 infection. In addition, although not everyone who is infected will develop an antibody response, appropriately validated serology tests, when used broadly, can be useful in understanding how many people have developed an adaptive immune response to the virus and how far the pandemic has progressed.

Serology tests can play a critical role in the fight against COVID-19 by helping health care professionals identify individuals who have antibodies to SARS-CoV-2 virus and have developed an adaptive immune response. In the future, this may potentially be used to help determine, together with other clinical data, whether these individuals may be less susceptible to infection. At this time, it is unknown for how long antibodies persist following infection and if the presence of antibodies confers protective immunity.“

https://www.fda.gov/medical-devices/coronavirus-covid-19-and-medical-devices/serologyantibody-tests-faqs-testing-sars-cov-2

A half a year later, the FDA updated their information and guidelines on antibody testing and immunity. Both of these following sources are from May 2021:

Antibody (Serology) Testing for COVID-19: Information for Patients and Consumers

“At this time, researchers do not know whether the presence of antibodies means that you are immune to COVID-19; or if you are immune, how long it will last.

In people who have received a COVID-19 vaccination, antibody testing is not recommended to determine whether you are immune or protected from COVID-19.

Many antibody tests are currently in development or available for use to detect antibodies to SARS-CoV-2. However, not all antibody tests that are being marketed to the public have been evaluated and authorized by the FDA.“

Understanding Antibody Test Results

Q: What does a positive antibody test mean?

A: If you have a positive test result on a SARS-CoV-2 antibody test, it is possible that you have recently or previously had COVID-19. There is also a chance that the positive result is wrong, known as a false positive. False positive tests may occur:

• Because antibody tests may detect coronaviruses other than SARS-CoV-2, such as those that cause the common cold.
• When testing is done in a population without many cases of COVID-19 infections. These types of tests work best in populations with higher rates of infection.

Q: Does a positive antibody test mean that I am immune to COVID-19?

A: A positive antibody test does not necessarily mean you are immune from SARS-CoV-2 infection, as it is not known whether having antibodies to SARS-CoV-2 will protect you from getting infected again. It also does not indicate whether you can infect other people with SARS-CoV-2.

Q: What does positive predictive value mean in antibody testing?

Positive predictive value is the probability that people who have a positive test result truly have antibodies. Positive predictive values for SARS-CoV-2 antibody tests are impacted by how common SARS-CoV-2 antibodies are in the population being tested at a certain time.

Predictive values are probabilities calculated using a test’s sensitivity and specificity, and an assumption about the percentage of individuals in the population who have antibodies at a given time (which is called “prevalence” in these calculations).

The lower the prevalence, the lower the predictive value. This means that COVID-19 antibody tests with high specificity used in areas with low prevalence (small number of people that have SARS-CoV-2 antibodies) will have a positive predictive value lower than in an area with higher prevalence.

Low positive predictive value may lead to more individuals with a false positive result. This could mean that individuals may not have developed antibodies to the virus even though the test indicated that they had. If a high positive predictive value cannot be achieved with a single test result, two tests may be used together to help identify individuals who may truly be SARS-CoV-2 antibody positive.

Q: What if I get different results on two tests from two different laboratories? Which one should I believe?

A: The test results from different laboratories may vary depending on several factors such as the accuracy of the test itself and also how long it may take for your body to develop antibodies after you had the coronavirus infection, if you were in fact infected. For this and other reasons, you should always review your test results with your health care provider.

https://www.fda.gov/medical-devices/coronavirus-covid-19-and-medical-devices/antibody-serology-testing-covid-19-information-patients-and-consumers

Antibody Testing Is Not Currently Recommended to Assess Immunity After COVID-19 Vaccination: FDA Safety Communication

Date Issued: May 19, 2021

“The U.S. Food and Drug Administration (FDA) is reminding the public and health care providers that results from currently authorized SARS-CoV-2 antibody tests should not be used to evaluate a person’s level of immunity or protection from COVID-19 at any time, and especially after the person received a COVID-19 vaccination.“

Recommendations for People Who Had or May Have a SARS-CoV-2 Antibody Test

• Be aware that SARS-CoV-2 antibody tests help health care providers identify whether someone has antibodies to SARS-CoV-2, the virus that causes COVID-19, indicating a prior infection with the virus. However, more research is needed to understand the meaning of a positive or negative antibody test, beyond the presence or absence of antibodies, including in people who received a COVID-19 vaccination, in people who have been exposed and have SARS-CoV-2 antibodies, and in people who are not fully vaccinated.
• If you have not been vaccinated: Be aware that a positive result from an antibody test does not mean you have a specific amount of immunity or protection from SARS-CoV-2 infection. If you have a positive test result on a SARS-CoV-2 antibody test, it means that it is possible you were previously infected with the SARS-CoV-2 virus. Talk with your health care provider about the meaning of your SARS-CoV-2 antibody test results.
• If you received a COVID-19 vaccination: Continue to follow the CDC’s recommendations for fully vaccinated people. Be aware that if you have a positive test result on a SARS-CoV-2 antibody test, it is possible you were previously infected with SARS-CoV-2. A COVID-19 vaccination may also cause a positive antibody test result for some but not all antibody tests. You should not interpret the results of your SARS-CoV-2 antibody test as an indication of a specific level of immunity or protection from SARS-CoV-2 infection. Talk to your health care provider or your state and local health departments if you have questions about whether an antibody test is right for you.

Recommendations for Health Care Providers

• At this time, do not interpret the results of qualitative, semi-quantitative, or quantitative SARS-CoV-2 antibody tests as an indication of a specific level of immunity or protection from SARS-CoV-2 infection after the person has received a COVID-19 vaccination. While a positive antibody test can indicate an immune response has occurred (seroconversion), and failure to detect such a response may suggest a lack of immune response, more research is needed. Currently authorized SARS-CoV-2 antibody tests are not validated to evaluate specific immunity or protection from SARS-CoV-2 infection. SARS-CoV-2 antibody tests should be ordered only by health care providers who are familiar with the use and limitations of the test. For more information about antibody tests for SARS-CoV-2, see Serology/Antibody Tests: FAQs on Testing for SARS-CoV-2.
• Be aware that vaccines trigger antibodies to specific viral protein targets. For example, currently authorized COVID-19 mRNA vaccines induce antibodies to the spike protein and not to nucleocapsid proteins that are likely detected only after natural infections. Therefore, COVID-19 vaccinated people who have not had previous natural infection will receive a negative antibody test result if the antibody test does not detect the antibodies induced by the COVID-19 vaccine. If you are considering antibody testing in vaccinated individuals, follow the Centers for Disease Control and Prevention’s guidelines for antibody testing. For more information about antibody test performance visit EUA Authorized Serology Test Performance.

“Test results from currently authorized SARS-CoV-2 antibody tests should not be used to evaluate a person’s level of immunity or protection from COVID-19. If the results of the antibody test are interpreted as an indication of a specific level of immunity or protection from SARS-CoV-2 infection, there is a potential risk that people may take fewer precautions against SARS-CoV-2 exposure. Taking fewer precautions against SARS-CoV-2 exposure can increase their risk of infection and may result in increased spread of SARS-CoV-2.”

https://www.fda.gov/medical-devices/safety-communications/antibody-testing-not-currently-recommended-assess-immunity-after-covid-19-vaccination-fda-safety

It is clear that the FDA has no understanding about what antibody test results mean nor what kind of immunity (if any) these invisible theoretical particles may provide. Let’s see what the CDC has to say about this. From the CDC in September 2021:

Antibody Testing Interim Guidelines

• Antibody testing does not replace virologic testing and should not be used to establish the presence or absence of acute SARS-CoV-2 infection.
• Antibody tests can vary in their individual performance characteristics; tests that have received Emergency Use Authorization (EUA)external icon may be used for public health and clinical purposes.
• Antibody tests yielding qualitative or semi-quantitative results have been issued EUAs; there currently is no recognized public health or clinical indication for preferential use of semi-quantitative tests.
• Virus-based neutralization assays are currently not authorized for emergency use by the U.S. Food and Drug Administration (FDA), although an enzyme-linked immunosorbent assay (ELISA)-based competitive neutralization test for qualitative detection of total neutralizing antibodies has been issued an EUA. Neutralization assays currently are being used as possible surrogates of protection in epidemiological and clinical studies.
• Antibody testing is not currently recommended to assess for immunity to SARS-CoV-2 following COVID-19 vaccination, to assess the need for vaccination in an unvaccinated person, or to determine the need to quarantine after a close contact with someone who has COVID-19. Some antibody tests will not detect the antibodies generated by COVID-19 vaccines. Because these vaccines induce antibodies to specific viral protein targets, post-vaccination antibody test results will be negative in persons without history of previous infection, if the test used does not detect antibodies induced by the vaccine.

“Although the immune correlates of protection are not fully understood, evidence indicates that antibody development following infection likely confers some degree of immunity from subsequent infection for at least 6 months (1, 2). However, it is not known to what extent emerging viral variants could impact protection from subsequent infection (3).”

“Efforts to better understand antibody kinetics, longevity of humoral immune responses, correlation of binding antibody levels to neutralizing antibodies, and serological surrogates of immune protection are dependent on wider availability of quantitative binding antibody assays that are standardized and traceable to an international standard.“

“Taken together, these findings in humans and non-human primates suggest that SARS-CoV-2 infection and development of antibodies can result in some level of protection against SARS-CoV-2 reinfection. The extent and duration of protection have yet to be determined.“

“It is not known to what extent persons re-infected with SARS-CoV-2 might transmit SARS-CoV-2 to others or whether the clinical spectrum differs from that of primary infection.“

“It is unknown whether infection confers a similar degree of immunity compared to vaccination.“

“Testing for antibodies that indicate prior infection could be a useful public health tool as vaccination programs are implemented, provided the antibody tests are adequately validated to detect antibodies to specific proteins (or antigens). Although an antibody test can employ specific antigens, antibodies developed in response to different proteins might cross-react (i.e., the tests might detect antibodies they are not intended to detect), and therefore, might not provide sufficient information on the presence of antigen-specific antibodies. For antibody tests with FDA EUA, it has not been established whether the antigens employed by the test specifically detect only antibodies against those antigens and not other antigens. Although current EUA indications do not preclude the use of these tests in vaccinated individuals, none of the currently authorized tests have been specifically authorized to assess immunity or protection of persons who have received a COVID-19 vaccine.“

“While it remains uncertain to what degree and for how long persons with detectable antibodies are protected against reinfection with SARS-CoV-2 or what concentration of antibodies are needed to provide such protection, cohort studies indicate 80%–90% reduction in incidence for at least 6 months after infection among antibody-positive persons (1, 2, 25). Longitudinal patient follow-up studies are ongoing to measure antibody levels before and after vaccination or infection to identify an association between responses below a certain threshold and vaccine failure or reinfection. These longitudinal patient follow-up studies are expected to elucidate the relationship between antibodies and protection from reinfection. In addition, T-cell-mediated adaptive immunity following infection, although not fully understood, likely contributes to protection from subsequent exposure to SARS-CoV-2 (45). It is also not known whether, and to what extent, viral evolution and the emergence of new SARS-CoV-2 variants could impact immunity from reinfection.“

“Accumulating evidence suggests that infection with SARS-CoV-2 with subsequent development of antibodies could confer some level of immunity for at least 6 months. However, the robustness and durability of immunity following infection and how it compares with vaccine-induced immunity remain unknown.“

https://www.cdc.gov/coronavirus/2019-ncov/lab/resources/antibody-tests-guidelines.html

It would appear that the CDC knows as little as the FDA.

In Summary (FDA):

• Serology (antibody) tests may detect different types of antibodies
• A serology test can yield a negative test result even in infected patients (for example, if antibodies have not yet developed in response to the “virus”) or may generate false positive results (for example, if antibodies to a “coronavirus” type other than the current pandemic novel strain is present)
• These tests should not be used to diagnose acute “COVID-19” infection
• Not everyone who is infected will develop an antibody response
• In the future, antibody tests may potentially be used to help determine, together with other clinical data, whether these individuals may be less susceptible to infection
• However, at this time, it is unknown for how long antibodies persist following infection and if the presence of antibodies confers protective immunity
• Researchers do not know whether the presence of antibodies means that you are immune to “COVID-19;” or if you are immune, how long it will last
• For the vaccinated, antibody testing is not recommended to determine whether you are immune or protected from “COVID-19”
• Not all antibody tests that are being marketed to the public have been evaluated and authorized by the FDA
• False positive antibody results occur:
  1. Because antibody tests may detect “coronaviruses” other than “SARS-CoV-2,” such as those that cause the common cold
  2. When testing is done in a population without many cases of “COVID-19” infections. These types of tests work best in populations with higher rates of infection.

For more information on the prevalence problem, see this post:

PCR and the Prevalence Problem

• A positive antibody test does not necessarily mean you are immune from “SARS-CoV-2” infection
• It is not known whether having antibodies to “SARS-CoV-2” will protect you from getting infected again
• It also does not indicate whether you can infect other people with “SARS-CoV-2”
• Positive predictive values for “SARS-CoV-2” antibody tests are impacted by how common “SARS-CoV-2” antibodies are in the population being tested at a certain time
• Predictive values are probabilities calculated using a test’s sensitivity and specificity, and an assumption about the percentage of individuals in the population who have antibodies at a given time (which is called “prevalence” in these calculations – see the linked PCR post above for more detail)
• The lower the prevalence, the lower the predictive value
• Low positive predictive value may lead to more individuals with a false positive result which could mean that individuals may not have developed antibodies to the “virus” even though the test indicated that they had
• The test results from different laboratories may vary depending on several factors such as the accuracy of the test itself and also how long it may take for your body to develop antibodies after you had the “coronavirus” infection, if you were in fact infected
• Results from currently authorized “SARS-CoV-2” antibody tests should not be used to evaluate a person’s level of immunity or protection from “COVID-19” at any time, and especially after the person received a “COVID-19” vaccination
• More research is needed to understand the meaning of a positive or negative antibody test, beyond the presence or absence of antibodies, including in people who received a “COVID-19” vaccination
• A positive result from an antibody test does not mean you have a specific amount of immunity or protection from “SARS-CoV-2” infection
• A “COVID-19” vaccination may also cause a positive antibody test result for some but not all antibody tests
• You should not interpret the results of your “SARS-CoV-2” antibody test as an indication of a specific level of immunity or protection from “SARS-CoV-2” infection
• Healthcare providers should not interpret the results of qualitative, semi-quantitative, or quantitative “SARS-CoV-2” antibody tests as an indication of a specific level of immunity or protection from “SARS-CoV-2” infection after the person has received a “COVID-19” vaccination
• While a positive antibody test can indicate an immune response has occurred (seroconversion), and failure to detect such a response may suggest a lack of immune response, more research is needed
• Currently authorized “SARS-CoV-2” antibody tests are not validated to evaluate specific immunity or protection from “SARS-CoV-2” infection
• “COVID-19” vaccinated people who have not had previous natural infection will receive a negative antibody test result if the antibody test does not detect the antibodies induced by the “COVID-19” vaccine
• One more time in case the FDA didn’t make it clear: Test results from currently authorized “SARS-CoV-2” antibody tests should not be used to evaluate a person’s level of immunity or protection from “COVID-19“

In Summary (CDC):

• Antibody testing should not be used to establish the presence or absence of acute “SARS-CoV-2” infection
• Antibody tests can vary in their individual performance characteristics
• There currently is no recognized public health or clinical indication for preferential use of semi-quantitative tests
• “Virus-based” neutralization assays are currently not authorized for emergency use by the U.S. Food and Drug Administration (FDA)
• Neutralization assays currently are being used as possible surrogates of protection in epidemiological and clinical studies
• Antibody testing is not currently recommended to assess for immunity to “SARS-CoV-2” following “COVID-19” vaccination, to assess the need for vaccination in an unvaccinated person, or to determine the need to quarantine after a close contact with someone who has “COVID-19”
• Some antibody tests will not detect the antibodies generated by “COVID-19” vaccines
• Post-vaccination antibody test results will be negative in persons without history of previous infection
• The immune correlates of protection are not fully understood

For more detail on correlation of protection, see this post:

Antibodies: No Correlation of Protection

• It is not known to what extent emerging “viral” variants could impact protection from subsequent infection
• Efforts to better understand antibody kinetics, longevity of humoral immune responses, correlation of binding antibody levels to neutralizing antibodies, and serological surrogates of immune protection are dependent on wider availability of quantitative binding antibody assays that are standardized and traceable to an international standard
• Some findings in humans and non-human primates suggest that “SARS-CoV-2” infection and development of antibodies can result in some level of protection against “SARS-CoV-2” reinfection, however the extent and duration of protection have yet to be determined
• It is not known to what extent persons re-infected with “SARS-CoV-2” might transmit “SARS-CoV-2” to others or whether the clinical spectrum differs from that of primary infection
• It is unknown whether infection confers a similar degree of immunity compared to vaccination
• Testing for antibodies that indicate prior infection could be a useful public health tool as vaccination programs are implemented, provided the antibody tests are adequately validated to detect antibodies to specific proteins (or antigens)
• Antibodies developed in response to different proteins might cross-react (i.e., the tests might detect antibodies they are not intended to detect), and therefore, might not provide sufficient information on the presence of antigen-specific antibodies
• For antibody tests with FDA EUA, it has not been established whether the antigens employed by the test specifically detect only antibodies against those antigens and not other antigens
• None of the currently authorized tests have been specifically authorized to assess immunity or protection of persons who have received a “COVID-19” vaccine
• It remains uncertain to what degree and for how long persons with detectable antibodies are protected against reinfection with “SARS-CoV-2” or what concentration of antibodies are needed to provide such protection
• Longitudinal patient follow-up studies are ongoing to measure antibody levels before and after vaccination or infection to identify an association between responses below a certain threshold and vaccine failure or reinfection
• T-cell-mediated adaptive immunity following infection is not fully understood
• It is also not known whether, and to what extent, viral evolution and the emergence of new “SARS-CoV-2” variants could impact immunity from reinfection
• The robustness and durability of immunity following infection and how it compares with vaccine-induced immunity remain unknown

When you look at the information (or lack thereof) all together, you find that both the FDA and CDC recommend against the use of antibody tests for diagnosis, recommend against the use of antibody tests to determine immunity, agree that antibody test results vary and are prone to false-positives, agree that these tests are non-specific and can cross-react with other “Coronaviruses,” agree that there is no known correlation of protection, agree that duration of immunity (if any) is unknown, etc. etc. etc. The list against these tests and the use of antibodies as any kind of meaningful measurement of anything is vast.

Guess we can put all of this ridiculous antibody nonsense behind us now?