Frequently asked questions

COVID-19 is a communicable respiratory viral infection caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). It was first identified in late 2019 and is responsible for the pandemic.

Symptoms of COVID-19 include fever, cough, fatigue/malaise, shortness of breath, myalgias, loss of taste, and loss of smell, among others. Severe COVID-19 illness may progress to respiratory and/or cardiovascular failure, blood clots and death.

1. Zou J., et al. “Robust SARS-CoV-2-specific T Cell Immunity is Maintained at 6 Months Following Primary Infection.” Nat Immunol. 2021
2. Channappanavar R, et al. “Virus-specific Memory CD8 T Cells Provide Substantial Protection From the Lethal Severe Acute Respiratory Syndrome Coronavirus Infection.” J Virol. 2014.
3. Ng, O, et al. “Memory T cell Responses Targeting the SARS Coronavirus Persist Up to 11 Years Post-infection.” Vaccine. 2016.

Visit CDC.gov  and/or your county’s public health department website to learn more about COVID-19, testing options, and vaccination schedules.

T cells are key players in the adaptive immune system. When the body is invaded by a foreign substance like a virus or bacteria, the immune system rallies one of its earliest lines of defense, helper T cells, to join the fight.

Helper T cells may call on their allies to kickstart antibody production to support the fight against the disease. Helper T cells also alert other types of T cells to the presence of foreign invaders to be targeted and destroyed.

After the body has fought off an infection or disease, a small number of T cells remain in the blood. They are called memory T cells and their job is to remember how to ward off these invaders if they ever return.

Early studies indicate that more than 40% of those who test positive for COVID-19 may be asymptomatic (do not have symptoms).¹ If you have had COVID-19, even if you did not experience symptoms, the immune system would still produce a T cell response.

1. Oran, D., et al. “Prevalence of Asymptomatic SARS-CoV-2 Infection.” Annals of Internal Medicine. September 2020.

T-Detect COVID is the first T cell test for COVID-19 available in the U.S. (not available in U.S. Territories) to those over age 18. It measures T cells instead of antibodies to detect recent or past SARS-CoV-2 infection (the virus that causes COVID-19).

T-Detect COVID can detect T cells in a blood sample and recognize the SARS-CoV-2 virus. T cells are the first responders of the adaptive immune system and activate the antibody response. While antibodies to SARS-CoV-2 (the virus that causes COVID-19) naturally wane and are detectable in the shorter term, T cell responders can persist in the blood long after antibody responses wane.^1,2,3  T cell testing can detect past COVID-19 for up to 10 months after symptoms appear (90% sensitivity).^1,2,4

1. Zou J., et al. “Robust SARS-CoV-2-specific T cell Immunity Is Maintained at 6 Months Following Primary Infection.” Nat Immunol. 2021.
2. Data on file. Adaptive Biotechnologies. 2021.
3. Dalai, S, et al. “Clinical Validation of a Novel T-Cell Receptor Sequencing Assay for Identification of Recent or Prior SARS-CoV-2 Infection.” medRxiv. 2020
4. Ng, O., et al. “Memory T Cell Responses Targeting the SARS Coronavirus Persist Up to 11 Years Post-infection.” Vaccine. 2016.

T-Detect COVID can detect an immune response to SARS-CoV-2, the virus that causes COVID-19 disease, to assess recent or past infection. It is not intended for the diagnosis of active/current SARS-CoV-2 infection. 

When T-Detect COVID was compared with serology testing:

• In one study, 15 or more days after symptom onset with PCR-diagnosed COVID-19, T-Detect COVID identified 94.5% of patients, while leading serology (antibody) tests had a test range from 88.0–90.4% at least 15 days post-diagnosis.¹
• In another study, five months after symptom onset, T cell testing detected 95% of COVID-19-positive-patients, while the serology (antibody) test had a range of 50-70% in detection of COVID-19-positive-patients.²
• In one study, T-Detect COVID showed a specificity of >99%.¹

1. Dalai, S, et al. “Clinical Validation of a Novel T-cell Receptor Sequencing Assay for Identification of Recent or Prior SARS-CoV-2 Infection.” medRxiv. 2021.
2. Elyanow, R., et al. “T-cell Receptor Sequencing Identifies Prior SARS-CoV-2 Infection and Correlates with Neutralizing Antibody Titers and Disease Severity.” medRxiv. 2021.

A T cell response is typically detectable in blood as early as several days after initial infection. How long this response lasts post-infection and the implications for immunity are not known.¹

The relationship between a demonstrable T cell response and the risk of infection is not well understood.

If you are fully vaccinated, the CDC states that you can participate in many of the activities that you did before the pandemic. To maximize protection from the Delta variant and prevent possibly spreading it to others, wear a mask indoors in public if you are in an area of substantial or high transmission. You should continue to wear a mask where required by laws, rules, regulations, or local guidance.

1. Zou J., et al. “Robust SARS-CoV-2-specific T Cell Immunity Is Maintained at 6 Months Following Primary Infection.” Nat Immunol. 2021.

T-Detect COVID can help you understand if you’ve had a recent or past COVID-19 infection. T cell testing can detect past COVID-19 for up to 10 months after infection (90% sensitivity).¹

T-Detect COVID can provide answers in these situations:

• You have lingering symptoms and wonder if you had COVID-19
• You may have been exposed to COVID-19 within the past 10 months, but never got tested and are concerned that you might have had COVID-19
• You were tested, but wonder if it may have been a false negative

The clinical significance of a positive adaptive T cell immune response to SARS‑CoV‑2 result for individuals who have received a COVID-19 vaccine is unknown.

The test is also appropriate for those interested in supporting COVID-19 research.

T-Detect COVID is not meant to diagnose an active infection.

1. Data on file. Adaptive Biotechnologies. 2021.

T-Detect COVID is only available to those over the age of 18. The test has not been validated for children under the age of 18, therefore Adaptive cannot accept or process orders for those under age 18.

At this time, T-Detect COVID is available to be prescribed by healthcare professionals in all U.S. states. It is not available in U.S. Territories.

For Hawaii, North Dakota and Vermont residents: Blood draw services via ExamOne, our mobile phlebotomy partner, are available in your state. Labcorp does not have locations in Hawaii, North Dakota or Vermont. Residents of these states should select the ExamOne blood draw option.

T-Detect COVID is only available in the U.S. and is not available in U.S. Territories.

T-Detect COVID is performed via a standard blood draw. You do not need to fast or prepare in any other way before the test is performed.

T-Detect COVID is used to detect a recent or past COVID-19 infection. PCR/antigen tests are used to diagnose a current COVID-19 infection. Talk to your doctor about which test is right for you.

T-Detect COVID has been granted Emergency Use Authorization by the FDA. For more information, visit the patient fact sheet or healthcare provider fact sheet.

Patients can order T-Detect COVID by answering some eligibility questions and submitting payment through the T-Detect website. An independent healthcare provider will evaluate your responses and authorize your test order, if appropriate.

If you choose mobile phlebotomy through ExamOne, Adaptive will ship you a test kit and ExamOne will schedule blood draw services via mobile phlebotomy (an in-home blood draw).

If you select a blood draw at a Labcorp Patient Service Center, PWNHealth will place an order with Labcorp. You can schedule an appointment or walk into any of Labcorp’s Patient Service Centers for a blood draw. Labcorp will have the appropriate materials to collect the blood sample, so you will not receive a test kit.

Adaptive will process the blood sample and share results with you via a secure email from PWNHealth. The estimated time for results is 7–10 days from shipment of blood sample (including 5–7 days for lab processing). Lab processing begins once all required provider and patient information is validated.

T-Detect COVID has been shown to have high sensitivity. However, in certain circumstances, including but not limited to the number of days since infection, the test may be negative despite a prior SARS-CoV-2 infection.

Physicians can partner with Adaptive by signing a business agreement, establishing an account and prepaying for kits. Contact us to learn more.

A kit for sample collection will be sent directly to you if you choose to have an ExamOne mobile phlebotomist (a blood draw technician) come to your home. You will need to give the test kit to them to use when collecting your blood sample.

If you choose to get your blood drawn at Labcorp, they will have the appropriate materials to collect the blood sample. You will not be shipped a test kit.

For those who selected ExamOne mobile phlebotomy, most test kits arrive within 3–5 days of test authorization.

If you choose to get your blood drawn at Labcorp, they will have the appropriate materials to collect the blood sample, so you will not receive a test kit.

The estimated time for results is 7–10 days from shipment of the blood sample (including 5-7 days for lab processing). Lab processing begins once all required provider and patient information is validated.

T-Detect COVID results are positive or negative. A positive test result with T-Detect COVID indicates that an adaptive T cell immune response to SARS-CoV-2 (the virus that causes COVID-19) was detected. A negative result indicates that past exposure to SARS-CoV-2 probably did not occur. T-Detect COVID has been shown to have high sensitivity. However, in certain circumstances, including but not limited to the number of days since infection, the test may be negative despite a prior SARS-CoV-2 infection.

The clinical performance has not been established in all circulating variants but is anticipated to be reflective of the prevalent variants in circulation at the time and location of the clinical evaluation. Performance at the time of testing may vary depending on the variants circulating, including newly emerging strains of SARS-CoV-2 and their prevalence, which change over time.

An abnormal result indicates that you likely had a recent or past SARS-CoV-2 infection (the virus that causes COVID-19). A “normal” result would be no T cell response to SARS-CoV-2, meaning no infection was detected.

During the public health emergency, we decided to make T-Detect COVID available for those who wanted to determine if they had a recent or past infection. At this time, we are unable to provide more information beyond a positive or negative result.

The impact of vaccination on T-Detect COVID results has not been established and the results from this test should not be interpreted as an indication or degree of protection from infection after vaccination. A recent research study showed that 75% of 333 patients with no known history of natural infection did have a positive T-Detect COVID result after being vaccinated against SARS-CoV-2.¹  More research is needed to better understand these results. We are actively gathering additional data and will provide updates as information becomes available.

1. Snyder TM, Gittelman RM, Klinger M, et al. Magnitude and Dynamics of the T-Cell Response to SARS-CoV-2 Infection and Vaccination. Oral presentation at: Infectious Disease (ID) Week. September, 2021; virtual conference. 

Consult your doctor regarding whether you should be vaccinated against SARS-CoV-2. As of June, 15, 2021, the CDC recommends vaccination for most people, even if they have had a natural infection with SARS-CoV-2.¹

1. “Frequently Asked Questions about COVID-19 Vaccination.” Centers for Disease Control and Prevention website. Updated June 15, 2021. Accessed Jan. 26, 2021. https://www.cdc.gov/coronavirus/2019-ncov/vaccines/faq.html

There are a few possible explanations:

• A PCR or antigen (molecular) test could have resulted in a false positive, meaning you did not have the disease and therefore would not have T cells.
• Studies show that T cells typically remain in the body long after antibodies, but it is unclear exactly how long they remain after a COVID-19 infection. Therefore, it is possible to have had COVID-19 and for T cells to have diminished by the time of testing to a number that is not detectable by laboratory tests.
• The clinical performance has not been established in all circulating variants but is anticipated to be reflective of the prevalent variants in circulation at the time and location of the clinical evaluation. Performance at the time of testing may vary depending on the variants circulating, including newly emerging strains of SARS-CoV-2 and their prevalence, which change over time

Talk with your doctor if you previously tested positive for COVID-19 and then tested negative for T cells.

A negative result indicates that past exposure to SARS-CoV-2 probably did not occur.

The clinical performance has not been established in all circulating variants but is anticipated to be reflective of the prevalent variants in circulation at the time and location of the clinical evaluation. Performance at the time of testing may vary depending on the variants circulating, including newly emerging strains of SARS-CoV-2 and their prevalence, which change over time.

A recent study demonstrated 90% of patients tested positive for T cells up to 10 months after a confirmed positive PCR test.¹ Data for T-Detect COVID greater than 10 months is not yet available. Therefore, it is possible that individuals who received a positive PCR result for SARS-CoV-2 (the virus that causes COVID-19) more than 10 months ago no longer have sufficient T cells to detect the past infection.

1. Data on file. Adaptive Biotechnologies. 2021

While no clinical test is 100% sensitive, in one study, T cell testing had a sensitivity of 95% at approximately five months after symptom onset.¹  In another study, T cell testing had a sensitivity of 90% at approximately 10 months after symptom onset.²  Sensitivity is the ability of a test to correctly determine if a person has or had the disease, so 95 out of 100 times T cell testing accurately determined if someone had the disease. That said, it is unclear exactly how long T cells remain after a COVID-19 infection. Therefore, it is possible to have had COVID-19 and for T cells to have diminished by the time of testing to a number that is not detectable by laboratory tests.

1. Elyanow, R., et al. “T-cell Receptor Sequencing Identifies Prior SARS-CoV-2 Infection and Correlates with Neutralizing Antibody Titers and Disease Severity.” medRxiv. 2021.
2. Data on file. Adaptive Biotechnologies. 2021.

In some instances, we are not able to determine a positive or negative result for recent or past exposure to SARS-CoV-2 (the virus that causes COVID-19). If this happens, your result will say “no result available.”

This may mean there was not enough T cell DNA in your sample, which can sometimes be caused by underlying medical conditions; in that case a new sample would not be expected to give a different result.

This may also mean there was a technical issue that prevented your blood sample from being tested properly, in which case a new blood sample may be useful. Call our Clinical Services team at 833-T-DETECT (833-833-8328) to discuss redoing your test at no cost.

There has been no CDC guidance on how much protection T cells can provide against the virus. The CDC has said that we do not know how much protection, or immunity, antibodies to the virus might provide against getting infected again. We recommend you visit the CDC for the most up-to-date information.

T-Detect COVID is not a substitute for a vaccine passport. Check with the airline and/or the country you are traveling to about COVID-19 testing and documentation requirements.

T-Detect COVID costs $150. Additional fees include test authorization ($9) and blood draw (on-site lab: $60 or in-home: $140).

The price does not represent the usual and customary charge for T-Detect COVID and is subject to change. T-Detect COVID is FSA/HSA eligible.

T-Detect COVID is not currently covered by insurance. The patient is responsible for blood draw fees and any additional associated costs. T-Detect COVID is FSA/HSA eligible.

Eligible patients may qualify for discounted testing based on their income or medical expenses as part of Adaptive’s patient support program (“Adaptive Assist”). You can print an  Adaptive Assist application and submit it to us at  AdaptiveBiotech@mylabbill.com or fax it to 440-788-2137. Alternatively, you can contact Adaptive at 855-236-9230 to find out if you might qualify for Adaptive Assist prior to placing your order.

If you have already purchased the test and your application for Adaptive Assist is approved to provide the test at a reduced cost, a refund will be processed to your credit card.

Eligible patients may qualify for discounted testing based on their income or medical expenses as part of Adaptive’s patient support program (“Adaptive Assist”). You can print an  Adaptive Assist application and submit it to us at  AdaptiveBiotech@mylabbill.com or fax it to 440-788-2137. Alternatively, you can contact Adaptive at 855-236-9230 to find out if you might qualify for Adaptive Assist prior to placing your order.

If you have already purchased the test and your application for Adaptive Assist is approved to provide the test at a reduced cost, a refund will be processed to your credit card.

Contact us at 833-T-DETECT (833-833-8328) within 24 hours if you wish to change or cancel your order. No refunds or cancellations can be made after 24 hours.

If we are unable to provide a laboratory report after you submit your blood sample, a refund will automatically be issued to the credit card you used and will be net of any costs for telehealth, phlebotomy, or other processing fees deducted. Contact us by phone at 833-T-DETECT (833-833-8328) or email.

ExamOne is a national mobile phlebotomy service provider that Adaptive Biotechnologies has partnered with to help provide blood draw services to patients.

Mobile phlebotomy is a mobile blood draw service in which a certified phlebotomist (someone trained to draw blood) visits your home or other location to collect a blood sample.

Labcorp is one of the largest clinical network laboratories in the U.S., with approximately 2,000 Patient Service Centers. If you select a Labcorp blood draw, a licensed phlebotomist (blood draw technician) will draw your blood at the Labcorp location you select after ordering T-Detect COVID.

Labcorp facilities are not available in North Dakota, Vermont or Hawaii.

PWNHealth is an independent healthcare provider network that provides oversight services to patients in connection with the laboratory testing they requested. PWNHealth and its services are independent from the laboratory and company from which patients request and register for T-Detect COVID.

Adaptive Biotechnologies follows all state and federal privacy rules, including the Health Insurance Portability and Accountability Act (HIPAA). Under the CARES Act, we are required to report results to appropriate public authorities.

Adaptive Biotechnologies follows all state and federal privacy rules, including the Health Insurance Portability and Accountability Act (HIPAA).

The Coronavirus Aid, Relief, and Economic Security (CARES) Act, requires “every laboratory that performs or analyzes a test that is intended to detect SARS-CoV-2 or to diagnose a possible case of COVID-19” to report the results from each such test to the Secretary of the Department of Health and Human Services (HHS). Additionally, the CDC states that the CARES Act requires laboratories to report all data to state or local public health departments using existing public health data reporting channels (in accordance with state law or policies).

Individuals with mild or asymptomatic COVID-19 may not mount a detectable antibody response and may instead resolve infection through a cellular immune response.^1,2

Traditional antibody (serology) tests measure IgM, IgG, and/or neutralizing antibodies to SARS-CoV-2 (the humoral component of the adaptive immune response). T-Detect COVID instead measures the cellular adaptive immune response to SARS-CoV-2 through T cell receptor sequencing.^1,3

When T-Detect COVID was compared with serology testing:

• In one study, 15 or more days after symptom onset with PCR-diagnosed COVID-19, T-Detect COVID identified 94.5% of patients, while leading serology (antibody) tests had a test range from 88.0–90.4% % at least 15 days post-diagnosis.³
• In another study, five months after symptom onset, T cell testing detected 95% of COVID positive patients, while the serology (antibody) test had a range of 50-70% in detection of COVID-19 positive patients.⁴
• In one study, T-Detect COVID showed a specificity of >99%.³

1. Long Q., et al. “Clinical and Immunological Assessment of Asymptomatic SARS-CoV-2 Infections.” Nat Med. 2020.
2.  Shields A.M., et al. “SARS-CoV-2 Seroconversion in Health Care Workers.” medRxiv. 2020.
3. Dalai, S., et al. “Clinical Validation of a Novel T-cell Receptor Sequencing Assay for Identification of Recent or Prior SARS-CoV-2 Infection.” medRxiv. 2021.
4. Elyanow, R., et al. “T-cell Receptor Sequencing Identifies Prior SARS-CoV-2 Infection and Correlates with Neutralizing Antibody Titers and Disease Severity.” medRxiv. 2021.

T-Detect COVID results are positive or negative. A positive test result with T-Detect COVID indicates that an adaptive T cell immune response to SARS-CoV-2 (the virus that causes COVID-19) was detected. A negative result indicates that past exposure to SARS-CoV-2 probably did not occur. T-Detect COVID has been shown to have high sensitivity. However, in certain circumstances, including but not limited to the number of days since infection, the test may be negative despite a prior SARS-CoV-2 infection.

The clinical performance has not been established in all circulating variants but is anticipated to be reflective of the prevalent variants in circulation at the time and location of the clinical evaluation. Performance at the time of testing may vary depending on the variants circulating, including newly emerging strains of SARS-CoV-2 and their prevalence, which change over time.

The impact of vaccination on results has not been established. The results from this test should not be interpreted as a degree of protection from infection after vaccination. A recent research study showed that 75% of 333 patients with no known history of natural infection had a positive T-Detect COVID result after being vaccinated against SARS-CoV-2.¹ More research is needed to better understand these results and Adaptive is actively gathering additional data.

1. Snyder TM, Gittelman RM, Klinger M, et al. Magnitude and Dynamics of the T-Cell Response to SARS-CoV-2 Infection and Vaccination. Oral presentation at: Infectious Disease (ID) Week. September, 2021; virtual conference.

Partner with Adaptive by signing a business agreement, establishing an account and prepaying for kits. Contact us  to learn more.

Contact us or call Clinical Services at 833-833-8328 to be connected to the team that handles contract pricing and to discuss an ordering process that works best for you and your employees.

We have several options. Adaptive will work with you to determine the ordering process that works best for you and your employees.

T-Detect COVID is not indicated for use in patients under age 18.

Adaptive does not share individual protected health information (PHI) with employers.

Results will be made available to the prescribing physician, who will then share the results with the patient.

Employers can access aggregated results that have been de-identified.

Employers can ask employees to consent to testing. Employer COVID-19 testing and screening protocols and policies should adhere to relevant state and local guidelines, which vary greatly by jurisdiction. Furthermore, general fundamental privacy law principles of transparency, notice, choice, and fairness should guide your practices.

T-Detect COVID is a T cell test, which determines recent or past exposure to SARS-CoV-2, the virus that causes COVID-19. It should not be used to determine active COVID-19 infection.

An employer may choose to administer COVID-19 RT-PCR testing to employees before initially permitting them to enter the workplace and/or periodically to determine if their presence in the workplace poses a direct threat to others.

The ADA does not interfere with employers following recommendations by the CDC or other public health authorities regarding whether, when, and for whom testing or other screening is appropriate. Federal and state guidelines should be consulted when determining back to work criteria and appropriateness of testing.

The immunoSEQ® Assay sequences the full repertoire in your samples and you will receive the immune receptor sequencing data on your samples where you can apply the immunoSEQ® T-MAP™ COVID Tool to identify SARS-CoV-2-specific TCRs in your samples.

T-Detect COVID should be applied where a positive/negative result will suffice for your research.

If you’d like to learn more about how you can use immunoSEQ or T-Detect in your research or clinical trials, please contact us.

Contact T-DetectResearch@adaptivebiotech.com with a brief description of your project or study and Adaptive will respond to discuss next steps.