FAQs Regarding SARS-CoV-2 PCR Testing

Updated: October 29, 2021

These FAQs provide information and guidance for Columbia University faculty, staff, and students who are undergoing diagnostic testing for SARS-CoV-2, the virus that causes COVID-19, through the Columbia University testing and contact tracing program. This guidance describes the type of test being used and the current understanding of the meaning of positive and negative PCR results in individuals with (symptomatic) and without (asymptomatic) symptoms.

Individuals who are SARS-CoV-2-positive, even without any symptoms, should self-isolate at home as described below.

Guidance for return to work and class is also described below.

There are two different types of tests for COVID-19; one determines whether one has it now (being the time the test was collected), and the other determines if one had it at some point in the past.

  • To diagnose a SARS-CoV-2 infection now, a nasal swab is used to detect the RNA of SARS-CoV-2 virus. This is the COVID-19 PCR test
  • To detect that an infection occurred at some point in the past, a serology blood test is done to detect antibodies to SARS-CoV-2

Note: The remainder of these FAQs apply to the COVID-19 PCR test.

Updated: October 29, 2021

All Columbia faculty, staff, and students are required to have initial COVID-19 gateway testing upon their first return to campus. For any affiliate not having been tested through the University program in 2021, tests must be done in the University surveillance program managed by Columbia Health and completed upon return to campus.

Tests performed at any other location (including NYP) will NOT fulfill the campus testing requirement.

If you are returning to University campuses and facilities after the gateway period ends on September 9, 2021, you will need a test before you can access Columbia facilities and campuses.  In general you will have the test one day and be able to have a greenpass on the ReOpenCU app the next day.  Please plan accordingly.

All students, faculty and staff are required to have a COVID-19 PCR test during the gateway period ending September 9, 2021, or upon their return to campuses and facilities if later in the term.

This graphic shows the process for gateway testing for Morningside students.

Barnard affiliates will be tested through Barnard's testing program.

Individuals who have had a positive COVID-19 diagnostic test in the prior 90 days may not need to undergo gateway testing or surveillance testing during the three months since COVID-19 diagnosis, unless they have symptoms of COVID-19. Please read the COVID-19 FAQs for more details.

The sites listed below are NOT for testing of individuals with symptoms, for family/household members, or for any other reason outside of the required Columbia University Test and Trace Program. Please visit the New York City Health and Hospitals website for additional testing resources.

Columbia University has five sites for COVID-19 testing for those who are eligible. The full details included addresses, dates and times of operation, and populations served can be found on the Testing Page.

Updated:  July 20, 2021

  • Testing schedules are opened 7-10 days in advance
  • Testing is available by appointment only; walk-ins are not accepted
  • If you arrive more than 10 minutes early you will be directed to wait outside the building until your scheduled time
  • If you arrive more than 10 minutes late you will be directed to leave the building and schedule a new appointment
  • Appointments cannot be scheduled by phone
  • If the date you prefer at a given location is not displaying options it indicates testing is not available at that location on that day (see above for locations and days/times) or all appointments are fully book. 
  • If the date and location is an available testing date and fully booked you should check other sites or the portal periodically to see if more capacity has been added or there have been cancellations. 
  • It is not possible to add to a fully booked schedule.
  • If you are unable to schedule through the Online Patient Portal, email [email protected] for assistance


Step by Step Instructions

  • To schedule your appointment, go to the Columbia Health Online Patient Portal
  • Sign in with your UNI and UNI password
  • Select "Appointments" from the main menu and select "schedule an appointment"
  • Select “COVID-19 testing” by location 
  • Answer the question regarding symptoms (these locations are for asymptomatic testing only)
  • Provide your callback number if prompted
  • Select the appointment day and time
  • Once your appointment is scheduled, the system will display a QR code. We encourage you to save the QR code to your phone as a screenshot or print it out. You can always access the code by logging back into the Online Patient Portal. The QR code is a touchless way to check in for your testing appointment
  • Complete your symptom self-screening (ReopenCU app) prior to coming to the testing center. Do not come if you are experiencing symptoms of COVID-19 (e.g., fever, cough, shortness of breath, sore throat, fatigue, muscle aches, loss of sense of smell or taste, or stomach upset). Those who are experiencing symptoms should self-isolate and contact their health care provider
  • Face covering is required when coming to your testing appointment
  • Bring your Columbia ID (if you have one) to your appointment. If you do not have your CUID yet, bring a photo ID and staff will be able to locate your record using your UNI or the QR code
  • Arrive at the time of your appointment; follow all directional signage and staff instructions
  • Individuals arriving early may be accommodated no more than 10 minutes before their scheduled time. If you are earlier you must wait outside of the respective buildings until your scheduled time
  • Individuals arriving late may be accommodated no more than 10 minutes after their scheduled time. If you are more than 10 minutes late you will not be admitted and must self-reschedule using the online system.
  • Have your ReOpenCU greenpass and appointment QR code ready to show on entry and to scan as you reach check-in
  • At the check-in desk, present your QR code for scanning. This will check you in for your appointment
  • You will be given a label for your specimen. This is your personal label and must not be dropped or lost
  • Complete the consent form (first time only)
  • You will then be directed into a testing booth
  • You will be instructed to:
    • Immediately apply your label to the specimen tube
    • Lower your face covering to under your nose but keep your mouth covered
    • Blow your nose well using the tissues provided, and dispose used tissues into the garbage can
    • Use the hand sanitizer provided
    • Follow the directions on the table with the observer watching you to collect your nasal swab, including opening the packaging, collecting the swab, and placing it back into the tube
    • Leave the tube containing your swab on the table in the testing booth
    • Use the hand sanitizer provided
    • Replace your face covering
  • Exit following the directional signage
  • The entire process should take less than 10 minutes

In general results are available within 72 hours.  You will receive either an email or a phone call when your results are available. In the event of a positive test result, you will be contacted by telephone and provided with guidance for isolation, care, and follow-up.

Emails will provide you with instructions on how to access your results:

  • When your results are available, you will receive an email to your Columbia email address from [email protected]
  • The email will alert you that your recent laboratory results are available and will require you to click a link contained in the email to register, using the registration code provided
  • Once you click the link, you will be brought to the Broad Institute Care Evolve page, where you will need to enter your Columbia email address and the registration code. For those with an @cumc.columbia.edu address, if this results in an error code, please try @columbia.edu format instead.
  • After confirming your identity, you will be asked to enter 2 security questions and answers, as well as a password
  • You will receive confirmation of your registration, and a second email will be sent with a link to your results
  • Once you click that link, you will have to enter the new code your received, and then log into the system using your email and password
  • You will be able to view and download your results by clicking on the test and date
  • Registration is only required the first time
  • For issues with registering to view your results, email [email protected].

On occasion the lab may not be able to process a sample.  In these events you will receive a secure message (patient portal), an encrypted email, or a phone call notifying you to return for a repeat of the test.  

Columbia is using an observed, self-collected nasal swab to detect SARS-CoV-2. You will be observed inserting a sterile, small, cotton-tipped swab gently into the anterior (front) part of both of your nostrils to obtain respiratory tract secretions. The swab is rotated, removed, and placed in a viral transport media and sent to the laboratories where the test will be done.  Written and verbal directions are available at all testing locations.  

Studies have noted that SARS-CoV-2 testing can show positive results for several weeks after confirmed COVID-19 disease. This may be due to detection of viral remnants, low level viral shedding or intermittent shedding, with no evidence that these individuals can transmit the infection to others.   

As such, the current CDC recommendation is that individuals with a positive SARS-CoV-2 diagnostic test in the prior 90 days do not need to undergo gateway testing or surveillance testing, unless they have symptoms of COVID-19.

If you are scheduled for a gateway or surveillance COVID-19 test and have had a positive COVID-19 test in the prior 90 days, you may be exempt from a repeat test during that period of time. In order to evaluate your exemption, here are the steps required:

  • Provide documentation of prior positive COVID-19 diagnostic test (antibody tests are not acceptable).    
    • This should be in a laboratory report; doctors notes are not acceptable
    • Report must contain your name and date of birth, as well as the type of test done, date of the test, and the result
  • Upload the documentation through the Columbia Health Online Patient Portal:
    • After log in, select “Downloadable Forms” from the left side menu
    • Select “Upload Positive COVID19 Test Results”
    • Select “Upload” and browse your computer for the file you would like to upload – PDF, .PNG, .JPG, .JPEG, or .GIF file formats are all acceptable
    • Verify upload; edit if needed or select “looks good” if you are satisfied with the image
    • Click the “save” button at the bottom of the page after uploading your document
  • Your documentation will be reviewed by a medical provider, and if it meets the criteria for an exemption, you will be notified that you have completed the University’s testing requirements, and the date of expiration of the exemption.
  • If you do receive an exemption but then become symptomatic, you should reach out to your health care provider as they may recommend a repeat COVID-19 test.

The laboratories that analyze the specimens will use assays to detect the SARS-CoV-2 viral genetic material (RNA). PCR assays can detect live virus, dead virus, or fragments of virus.

A positive PCR test from an individual with symptoms means that a person has COVID-19 and can transmit the infection to others. These individuals need to be isolated. In order to return to work or class, all of the following criteria must be met:

  • At least 10 days have passed since the onset of symptoms
  • At least 24 hours have passed without fever without the use of antipyretic medications, e.g., acetaminophen (Tylenol), ibuprofen (Advil, Motrin)
  • Marked improvement in symptoms

Note: When these individuals return to work/class, they need to continue to use all protective measures against COVID-19 (e.g., use of face covering, adherence to physical distancing) because we do not know yet if someone can be re-infected with SARS-CoV-2.

The PCR test can detect both live and dead virus, or viral RNA fragments.

A positive PCR result in someone without symptoms could mean any of the following:

  • A person is pre-symptomatic or asymptomatic, meaning they may or may not develop symptoms, but is shedding the virus. Asymptomatic or pre-symptomatic people who are PCR-positive can sometimes transmit SARS-CoV-2 to others
  • A person has recovered from the virus, but is still shedding the virus and could transmit SARS-CoV-2 to others
  • A person has recovered from COVID-19, but the PCR is detecting dead virus or viral RNA fragments, and SARS-CoV-2 cannot be transmitted to others

This is why asymptomatic individuals who are SARS-CoV-2-positive will need to self-isolate. They can return to work or class as long as they remain symptom free after 10 days have passed since the date that their swab was obtained. The nasal swab PCR testing should NOT be repeated before the individual can return to work or class.

Individuals with positive PCR tests should obtain guidance regarding their health and how to protect their close contacts from their primary care provider or campus health service.

Note: When these individuals return to work or class, they need to continue to use all protective measures against COVID-19 because we do not know yet if someone can be re-infected with SARS-CoV-2.

No, individuals can return to work or class as described above. No further PCR testing is required to return to work or class.

A person can potentially test positive for up to 90 days after infection even though they would not be able to infect others.  As such repeat testing in the 90-day period is not advised.

Contact health provider to seek advice and care. Before seeking care, an individual should call their provider to help coordinate care.

  • Individuals should put a face mask before being around anyone else and before entering a health care facility
  • Call 911 if there is a medical emergency like significant shortness of breath

People with symptoms consistent with COVID-19 may have a negative test for several reasons:

  • A negative test from an individual who previously had symptoms and is now well may mean that a person has cleared the virus and can’t transmit the virus to others
  • This may be a false negative test meaning that the person does have COVID-19, but that the PCR test did not detect the virus because the level of viral RNA was below the limit of detection. Levels of viral RNA are usually highest in the first 5 days of illness
  • False negative tests can also occur due to inadequate or improper nasal swab collection or problems in the transport of the specimen
  • Symptoms may not be indicative of COVID-19 as most of the symptoms are not specific for COVID-19 and could indicate another infection or seasonal allergies or asthma

It is highly likely that a person without symptoms with a negative PCR test does not have COVID-19 at this point in time. These individuals should observe all preventive measures and  self-monitor for symptoms of COVID-19.

If an individual has a negative PCR test result but has had close contact with a person who is known to be positive, this individual should self-quarantine and continue to self-monitor for symptoms of COVID-19 for 10 days from the time of last exposure as there is continued risk of transmission.

Updated: October 29, 2021

Vaccinated individuals can participate in campus activities while waiting for their initial gateway PCR test result. For unvaccinated individuals with approved exemptions, gateway PCR tests must be completed PRIOR to participation in campus activities (work or class).

Note: All unvaccinated Columbia affiliates (faculty, staff, and students) arriving from outside the United States are required to quarantine for 7 days upon arrival as recommended by CDC and complete a tests on day 3-5 of their quarantine.

For individuals undergoing testing through the ongoing surveillance program (after the gateway test), either regularly or as part of the weekly random sample, the individual can continue to work, go to class, and participate in campus activities while waiting for their test result, as long as they have no symptoms. They should continue to observe all prevention measures. If asymptomatic individuals with close contact of a COVID-19 case get tested, such individuals should self-quarantine for 10 days from the time of exposure, even if they receive a negative test result during the self-quarantine period.

Note: For individuals in patient-facing positions, self-quarantine of close contacts is not required, consistent with NewYork-Presbyterian Hospital policies for health care workers.

Occasionally, a person will have an invalid or unsatisfactory (TNP) PCR test result. There are many reasons for these incomplete results and individuals should make no assumptions regarding an invalid or unsatisfactory test.  This person SHOULD have a repeat swab sent for SARS-CoV-2 testing through the Columbia testing site.  Undergraduate students should not schedule an additional test, simply be sure to have your next required test.

Yes.  If an individual tests positive through the Columbia Test and Trace Program, both the Columbia Test and Trace Program and the New York City Department of Health will be notified of the test result.  Those testing positive outside of the University testing program are required to report their positive test to [email protected] so that contact tracing can be completed.

The Columbia University Test and Trace Program assists the city and state with their efforts in contact tracing. The Columbia program will interview the individual to assess other Columbia close contacts and will notify these individuals of their potential exposure (without disclosure of the index case’s name or other information). They will be provided appropriate guidance regarding self-quarantine and testing, and provided the necessary support, in addition to maintaining confidentiality. New York City or state is responsible for identifying and tracing the contacts of the case outside of Columbia.

If you test positive for SARS-CoV-2, you will be contacted by a Columbia University health care provider to discuss your positive result and provide you with guidance on isolation and self-care.

Faculty and staff should also notify their health care provider of their positive test.

Students will be connected with their campus health service (Columbia Health for Morningside students and CUIMC Student Health Service for CUIMC students) for care and support. This will include daily telehealth medical check-ins and access to psychological and mental health support.

You must follow the guidance of your health care provider regarding discontinuation of isolation. For those with symptoms, this usually occurs when:

  • At least 10 days have passed since symptom onset and
  • At least 24 hours have passed since resolution of fever without the use of fever-reducing medications and
  • Other symptoms have improved

For those with a positive test who never develop symptoms, isolation can be discontinued 10 days after the date of the first positive PCR test.

Repeat testing for individuals in isolation is not recommended by the Centers for Disease Control and Prevention (CDC), based on evidence that individuals who have completed the time course described above are no longer infectious and that some individuals may continue to have positive PCR tests due to viral debris or noninfectious particles that may be detected by the PCR assay.

Students who test positive should contact Columbia Health (Morningside campus) or Student Health Service (CUIMC) for clearance to return to campus activities. Faculty and staff may be asked to provide appropriate documentation to Human Resources prior to their return.

There will not be a charge for the visit or for the swabbing to obtain a sample through the Columbia Test and Trace Program for those eligible for the gateway testing or ongoing surveillance testing, and costs will be covered in full by the University.

It depends. Please follow the guidance on the Quarantine section of this website. 

The information provided herein is based on current knowledge and is subject to change as new information becomes available.