Frequently asked questions about UBI SARS-CoV2 ELISA

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Who is the UBI Group? 

UBI Group was founded in 1985 and currently has over 5 operating entities and 950 employees globally. We have facilities in China, Taiwan, Ireland and the US. For the past three decades, we have developed, manufactured and sold HIV, HCV, HTLV and FMDV blood diagnostic kits worldwide through various distribution partners including Organon Teknika and BioMerieux. We have also developed, manufactured and sold over 4.5 billion vaccines and ~500 million doses annually through partners. Dr. Chang Yi Wang, our Chief Scientific Officer, is inventor and author of over 100 patents and peer-reviewed publications. She has, together with the UBI team, pioneered the employment of antigenic peptides in the development of  4 blood screening test kits for detection of antibodies to HIV, HCV, HTLV I/II and FMDV for identification and differentiation of viral infections and 2 licensed synthetic peptide based vaccines (FMDV and LHRH) which are globally distributed. She has been awarded Inventor of the Year Award (NYPLA), Pioneer in Technology Award (BMSF), and recipient of funding from Gates Foundation, MOEA and multiple NIH grants over $20M, including for SARS antibody screening diagnostic work. She is currently collaborating with Dr. Anthony Fauci/NIAID and colleagues on HIV functional cure program, and discussed extensively with Dr. Redfield in this area, both leaders in the coronavirus response today.

What is a COVID-19 antibody test and what do the results tell me?

After a person is infected with SARS-CoV-2, the virus that causes the coronavirus disease, 2019 (COVID-19), that person’s immune system will produce antibodies against the virus to fight the infection.  A COVID-19 antibody test is able to detect these antibodies from a small sample of blood to diagnose whether a person currently has (or previously had) COVID-19.  

The FDA announced on March 16, 2020 that antibody tests can be used immediately to help control the COVID-19 pandemic. 

How does the UBI® SARS-CoV-2 ELISA work?

Our test, called the UBI® SARS-CoV-2 ELISA, is a qualitative enzyme-linked immunosorbent assay (ELISA) that detects antibodies to SARS-CoV-2 in human sera or plasma.  

The SARS-CoV-2 virus has four structural proteins known as the S (spike), E (envelope), M (membrane), and N (nucleocapsid) proteins.  After infection with the virus, a person’s immune system will produce antibodies that specifically bind to portions of the M, S, N, and E proteins to help the cells of the immune system to fight and rid the body of the virus.  The antibodies circulate throughout the body so that they can bind to, and help get rid of, the virus. It takes about 8 to 10 days after being infected with the virus for the body to produce enough antibodies to be detected in a blood sample using an antibody test, including the UBI® SARS-CoV-2 ELISA.  The antibodies remain in the body for a long time, even after the infection is over, to ensure that the virus has been completely eradicated. 

Our test uses small protein fragments, call peptides, that were carefully selected from the M, S, and N proteins of SARS-CoV-2.  The peptides we use were synthesized in a lab using a machine, which means that they were not isolated from the active virus or produced using bacteria or other methods.  Thus, the peptides we use are very clean and free of impurities that may be present if the peptides were produced using a different method. The synthetic peptides in our test are able to capture and bind to antibodies produced by the body in response to infection from the SARS-CoV-2 virus.  

The UBI® SARS-CoV-2 ELISA will determine if antibodies against the virus are present in a small blood sample.  If SARS-CoV-2 antibodies are detected in the blood sample using our test, then the result will be considered “positive”.  If SARS-CoV-2 antibodies are not detected, then the result will be considered “negative”.

How specific and sensitive is the UBI® SARS-CoV-2 ELISA?

As of March 19, 2020, we have performed validation tests that have demonstrated the UBI® SARS-CoV-2 ELISA to be highly sensitive, specific, and accurate.  

We have already tested over 900 blood samples that were collected before the present COVID-19 outbreak and none of these samples tested positive using our test, which means that our test has not produced even one false positive result to-date.  These samples included blood samples from patients who have previously tested positive for other human coronaviruses (e.g., NL63 or HKU-1) as well as other infectious diseases (e.g., HIV, HCV, and HBV).  

In addition, as of March 19, 2020, 100% of the blood samples collected at day 10 or later after infection from SARS-CoV-2 from patients who tested positive to COVID-19 by other methods were also found to be positive using the UBI® SARS-CoV-2 ELISA.  

We are continuing to validate the UBI® SARS-CoV-2 ELISA to ensure that it is highly sensitive, specific, and accurate and will update the answer to this question if any information changes.  However, based on our initial validation tests as of March 19, 2020, the key features of our test include:

  • Accurate — 100% specificity and sensitivity
  • Precise — can differentiate between SARS-CoV-2 vs. other coronaviruses circulating in US
  • Fast — results in 2-3 hours
  • Scalable — can be deployed to screen hundreds or thousands of subjects easily

Why is the UBI® SARS-CoV-2 ELISA better than other antibody tests?

Accuracy, sensitivity, and specificity.  

Several companies have announced the production of rapid antibody tests that can provide results in about 15 minutes to determine if you a patient has COVID-19.  Unfortunately, the common problem with these rapid tests is that they can be highly inaccurate and provide false positive or false negative results. Some companies that have applied for an Emergency Use Authorization (EUA) with the FDA have acknowledged that their rapid tests are only about 90% accurate, based on initial testing using samples from patients who have previously tested positive to COVID-19 by other methods.  The accuracy, sensitivity, and specificity of other antibody tests can vary greatly depending on how they were developed due to a number of factors. 

In contrast, the UBI® SARS-CoV-2 ELISA was developed by the UBI Group who has over 30 years of experience in developing, manufacturing, and distributing blood diagnostic kits worldwide, including kits for HIV, HCV, HTLV and FMDV.  Validation tests have demonstrated that the UBI® SARS-CoV-2 ELISA is highly sensitive, specific, and accurate. In fact, we have tested over 900 blood samples that were collected before the present COVID-19 outbreak and none of these samples tested positive using our test, which means that our test has not produced even one false positive result to-date.  These samples included blood samples from patients who have previously tested positive for other human coronaviruses (e.g., NL63 or HKU-1) as well as other infectious diseases (e.g., HIV, HCV, and HBV). In addition, as of March 19, 2020, 100% of the blood samples collected at day 10 or later of infection from patients who tested positive to COVID-19 by other methods were also found to be positive using the UBI® SARS-CoV-2 ELISA.  

Therefore, the UBI® SARS-CoV-2 ELISA is highly sensitive, specific, and accurate in determining if a patient has been infected with SARS-CoV-2 compared to antibody tests developed by others.

What about the current RT-PCR tests being used? How is this different?

The need for large-scale testing has become apparent in the past weeks. While the RT-PCR nasal swab tests currently being used are helpful to test active infections, there are important limitations and restrictions. These include variability in accuracy with high false negatives (up to 50%), difficulty to scale up to test large populations of people, and the ability to only detect active infection but inability to determine if someone has been previously infected but recovered. As a result, the RT-PCR tests have been restricted in application, challenging to roll out, and unable to inform public health officials the true scope of outbreak.

On March 11, 2020, the CDC called for use of antibody tests and the WHO urged all outbreak areas to immediately begin testing with such tests to better track and contain community spread of the virus. 

How can communities use large scale screening using these tests?

We have had many governments and corporations inquire about large-scale testing. Antibody tests can be used as a quick screen to identify who has been infected within a community. This can provide leaders, public health officials, and the public with more accurate information about the prevalence of infection in a given population, which can help everyone take steps to contain community spread. 

Antibody tests, such as the UBI® SARS-CoV-2 ELISA, can be used to complement RT-PCR tests for a more accurate diagnosis of current infection in symptomatic patients. It can also identify those who have been infected, but have already recovered and developed a level of immunity to the virus. People who have not yet been exposed are still susceptible to the virus and should exercise caution and social distancing to avoid infection. In addition, people may get infected but not know that they are infected because they either have mild symptoms or no symptoms at all.  These people, with mild or no symptoms, are still able to spread the virus to others who may be more at risk in developing severe infections. Therefore, large-scale testing is important to understand this information, which can help communities stay safe while staying open. 

Disclaimer

According to the FDA’s “Policy for Diagnostic Tests for Coronavirus Disease-2019 during the Public Health Emergency” issued on March 16, 2020, we are required to inform you of the following information:

  • This test has not been reviewed by the FDA.
  • Negative results do not rule out SARS-CoV-2 infection, particularly in those who have been in contact with the virus. Follow-up testing with a molecular diagnostic should be considered to rule out infection in these individuals.
  • Results from antibody testing should not be used as the sole basis to diagnose or exclude SARS-CoV-2 infection or to inform infection status.
  • Positive results may be due to past or present infection with non-SARS-CoV-2 coronavirus strains, such as coronavirus HKU1, NL63, OC43, or 229E.
  • This test is not for the screening of donated blood 
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