Interim Guidance for SARS-CoV-2 Testing and Screening at Institutions of Higher Education (IHEs)
For College and University Administrators
Summary of Recent Changes
- Updates were made to reflect changes to CDC’s Overview of Testing for SARS-CoV-2.
- Updates were made to recommend universal entry screening prior to the beginning of each term and serial screening testing when testing capacity is sufficient.
- Updates were made to reflect CDC revised quarantine guidelines and include considerations for a shortened quarantine period in consultation with local health departments.
- Updates were made to include considerations for COVID-19 surveillance, vaccination, and health equity.
- The following guidance is meant to help college and university administrators protect students, faculty, staff, and adjacent communities to slow the spread of SARS-CoV-2, the virus that causes COVID-19.
- IHEs should implement an entry screening strategy prior to the beginning of each term.
- IHEs should implement a universal serial screening testing strategy in the context of moderate, substantial, or high community transmission of SARS-CoV-2 if sufficient testing capacity is available.
- All COVID-19 prevention plans should be developed in consultation with local public health authorities and should include testing strategies and actions to support testing (e.g., isolation and quarantine).
Testing to rapidly detect and isolate infectious individuals can reduce transmission of SARS-CoV-2, the virus that causes COVID-19. People living and working in congregate settings, including institutions of higher education (IHEs), are at increased risk for COVID-19.1 As such, there are special considerations for college and university administrators when planning for SARS-CoV-2 screening and diagnostic testing.
The following guidance is meant to help college and university administrators protect students, faculty, staff, and adjacent communities and slow the spread of SARS-CoV-2. All prevention plans, including testing strategies, should be developed in consultation with local public health authorities. Testing capacity and needs will vary widely across IHEs and the communities in which they are situated, and over time, as SARS-CoV-2 transmission fluctuates. This document provides recommendations for entry screening and serial screening testing strategies and discusses general actions to support testing. This document is intended to provide guidance on the types of testing and intended uses of testing for SARS-CoV-2 in light of additional testing capacity throughout the country and does not address decisions regarding payment for or insurance coverage of such testing. This guidance is an update to the “Interim Considerations for Institutions of Higher Education Administrators for SARS-CoV-2 Testing” initially posted on June 30, 2020.
Testing to rapidly detect and isolate infectious individuals can reduce SARS-CoV-2 transmission, and should be one component of written comprehensive COVID-19 prevention plans for IHEs. If IHEs offer widespread testing, individuals with mild symptoms, those who have symptoms but thought they were not ill with COVID-19, and those with pre-symptomatic and asymptomatic infections might be identified. Implementation of CDC testing guidance can help IHEs protect students, faculty, staff, and adjacent communities and slow the spread of SARS-CoV-2.2 Prevention strategies (e.g., vaccination, physical distancing, correct and consistent use of face masks, hand hygiene, cleaning regularly, and appropriate ventilation) should be implemented along with all testing strategies.3
CDC has no regulatory authority over testing. Therefore, the information in this document is meant to assist health departments and IHEs in making decisions rather than establish any regulatory requirements. IHEs are encouraged to work closely with their local public health authorities to develop plans and protocols appropriate for their jurisdiction.
IHEs vary considerably in geographic location (which can differ in levels of community transmission), size, administrative structure, funding, and organization. IHEs also vary considerably in the proportion of total student population living on campus, in off-campus housing near the IHE, or commuting. Testing capacity and needs also vary in IHEs and adjacent communities. Given these variations, IHE officials should determine, in collaboration with local public health departments, the best strategies for screening testing and diagnostic testing of symptomatic cases. IHEs and health departments should have a plan for actions to be taken for those with positive test results and their close contacts.1
SARS-CoV-2 testing may be incorporated as part of a comprehensive approach to reducing transmission. Symptom screening, testing, and contact tracing are strategies to identify people infected with SARS-CoV-2 so that actions can be taken to slow and stop the spread of the virus.
COVID-19 vaccine is currently available in limited doses; therefore, CDC’s Advisory Committee on Immunization Practices (ACIP) described recommendations for prioritization during the early phases of the vaccination program. As vaccine supply increases and additional priority groups receive vaccine, CDC’s priorities for SARS-CoV-2 testing will change and the guidance will be updated. For example, as more IHE faculty are vaccinated, SARS-CoV-2 testing priorities may shift to focus on unvaccinated faculty, staff, and students. For guidance on quarantine and testing of fully vaccinated people, please visit Interim Public Health Recommendations for Fully Vaccinated People.
People undergoing testing should receive clear information on
- the manufacturer and name of the test, the type of test, the purpose of the test, the performance specifications of the test, any limitations associated with the test, who will pay for the test, how the test will be performed, how and when they will receive test results, and;
- how to understand what the results mean, actions associated with negative or positive results, the difference between testing for workplace screening versus for medical diagnosis, who will receive the results, how the results may be used, and any consequences for declining to be tested.
Individuals tested are required to receive patient fact sheets as part of the test’s emergency use authorization (EUA)external icon.
There are many categories of tests used to detect SARS-CoV-2. The selection and interpretation of SARS-CoV-2 tests should be based on the context in which they are being used.
Viral tests authorizedexternal icon by the Food and Drug Administration (FDA) are used to diagnose infection with SARS-CoV-2, the virus that causes COVID-19. Viral tests evaluate whether the virus is present in respiratory or other specimens. Results from these tests help public health officials identify and isolate people who are infected to minimize SARS-CoV-2 transmission. See FDA’s list of In Vitro Diagnostics Emergency Use Authorizationsexternal icon for more information about the performance of specific authorized tests.
- Nucleic acid amplification tests (NAATs), such as real-time reverse transcription-polymerase chain reaction (RT-PCR), detect viral ribonucleic acid (RNA) and indicate a current infection or a recent infection with prolonged viral RNA detection but without direct evidence for virus capable of replicating or of being transmitted to others. NAATs are high-sensitivity, high-specificity tests for diagnosing SARS-CoV-2 infection. Most NAATs need to be processed in a laboratory with variable time to results (~1–2 days), but some NAATs are point-of-care tests with results available in about 15–45 minutes.
- Antigen tests detect the presence of a specific viral antigen. Most can be processed at the point of care with results available in about 15–30 minutes. Antigen tests generally have similar specificity but are less sensitive than NAATs. Depending on the pre-test probability, antigen test results may need confirmation with a NAAT (e.g., a negative test in persons with symptoms or a positive test in persons without symptoms). Use of the Antigen Testing Algorithm pdf icon[147 KB, 1 page] is recommended to determine when confirmatory testing is needed.
Antibody (or serology) tests are used to detect previous infection with SARS-CoV-2 and can aid in the diagnosis of Multisystem Inflammatory Syndrome in Children (MIS-C) and in adults (MIS-A). CDC does not recommend using antibody testing to diagnose current infection. Depending on the time when someone was infected and the timing of the test, the test might not detect antibodies in someone with a current infection. In addition, it is not currently known whether a positive antibody test result indicates immunity against SARS-CoV-2; therefore, at this time, antibody tests should not be used to determine if an individual is immune against reinfection. Antibody testing is being used for public health surveillance and epidemiologic purposes. Because antibody tests can have different targets on the virus, specific tests might be needed to assess for antibodies originating from past infection versus those from vaccination. For more information about COVID-19 vaccines and antibody test results, refer to Interim Clinical Considerations for Use of mRNA COVID-19 Vaccines Currently Authorized in the United States.
For more information, please refer to Overview of Testing for SARS-CoV-2.
For more detailed information about tests to detect SARS-CoV-2, visit Overview of Testing for SARS-CoV-2. CDC recommendations for SARS-CoV-2 testing are based on what is currently known about the virus. SARS-CoV-2 is a newly identified pathogen and knowledge about the virus and the course of disease continues to emerge. Information on testing for SARS-CoV-2 will be updated as more information becomes available.
Diagnostic testing is intended to identify current infection in individuals and is performed when a person has signs or symptoms consistent with COVID-19, or when a person is asymptomatic but has recent known or suspected exposure to SARS-CoV-2.
Examples of diagnostic testing include:
- Testing people who have symptoms consistent with COVID-19 and who present to their healthcare provider
- Testing people as a result of contact tracing efforts
- Testing people who indicate that they were exposed to someone with a confirmed or suspected case of COVID-19
- Testing people who attended an event where another attendee was later confirmed to have COVID-19
Screening tests are intended to identify infected people who are asymptomatic and do not have known, suspected, or reported exposure to SARS-CoV-2. Screening helps to identify unknown cases so that measures can be taken to prevent further transmission.
Examples of screening include:
- Testing employees in a workplace setting
- Testing students, faculty, and staff in a school or university setting
- Testing a person before or after travel
- Testing at home for someone who does not have symptoms associated with COVID-19 and no known exposures to someone with COVID-19
When choosing which test to use, it is important to understand the purpose of the testing (e.g., diagnostic, screening), analytic performance of the test within the context of the level of community transmission, need for rapid results, and other considerations. Table 1 summarizes some characteristics of NAATs and antigen tests to consider. Most antigen tests that have received EUA from FDAexternal icon are authorized for testing symptomatic persons within the first 5, 7, 12, or 14 days of symptom onset. Given the risk of transmission of SARS-CoV-2 from asymptomatic and presymptomatic persons with SARS-CoV-2 infection, use of antigen tests in asymptomatic and presymptomatic persons can be considered. FDA has provided a list of FAQ for healthcare providers who are using diagnostic tests in screening asymptomatic individualsexternal icon, and the Centers for Medicare & Medicaid Services will temporarily exercise enforcement discretionexternal icon to enable the use of antigen tests in asymptomatic individuals for the duration of the COVID-19 public health emergency under the Clinical Laboratory Improvement Amendments of 1988 (CLIA). Laboratories that perform screening or diagnostic testing for SARS-CoV-2 must have a CLIA certificate and meet regulatory requirements. Tests that have received an EUA from FDA for point of care (POC) use can be performed with a CLIA certificate of waiver.
Table 1. NAAT and Antigen Test Differences to Consider When Planning for Diagnostic or Screening Use
Detect current infection*
Detect current infection
Viral Ribonucleic Acid (RNA)
Nasal, Nasopharyngeal, Oropharyngeal, Sputum, Saliva
Varies by test, but generally high for laboratory-based tests and moderate-high for POC tests
Varies depending on the course of infection, but generally moderate-to-high at times of peak viral load*
Varies by Test
Relatively Easy to Use
Authorized for Use at the Point-of-Care
Most are not, some are
Most are, some are not
Most 1-3 days. Some could be rapid in 15 minutes
Ranges from 15 minutes to 30 minutes
Most sensitive test method available
Short turnaround time for NAAT POC tests, but few available
Usually does not need to be repeated to confirm results
Short turnaround time (approximately 15 minutes)
When performed at or near POC, allows for rapid identification of infected people, thus preventing further virus transmission in the community, workplace, etc.
Comparable performance to NAATs in symptomatic persons and/or if culturable virus present, when the person is presumed to be infectious
Longer turnaround time for lab-based tests (1–3 days)
Higher cost per test
A positive NAAT diagnostic test should not be repeated within 90 days, since people may continue to have detectable RNA after risk of transmission has passed
May need confirmatory testing
Less sensitive (more false negative results) compared to NAATs, especially among asymptomatic people
*The decreased sensitivity of antigen tests might be offset if the point-of-care antigen tests are repeated more frequently (i.e., serial testing at least weekly).
§Costs for: NAATsexternal icon, Antibody testsexternal icon
Testing persons with signs or symptoms consistent with COVID-19
People with COVID-19 signs or symptoms, regardless of vaccination status, should be immediately separated from others (e.g., students, employees, visitors), masked (if not already), and sent home to isolate or to a campus-sponsored isolation room/floor/building. If symptoms are severe, they should be sent to a healthcare facility for medical care. The Coronavirus Self-Checker is a tool to help people make decisions on when to seek testing and appropriate medical care. CDC recommends that anyone with signs or symptoms of COVID-19 get tested and follow the advice of their healthcare provider. People with COVID-19 signs or symptoms should only leave isolation to get tested or receive medical care. For more information on test result interpretation, see the Overview of Testing for SARS-CoV-2.
Positive test results using a viral test (NAAT or antigen) in people with signs or symptoms consistent with COVID-19 indicate that the person has COVID-19. A negative antigen test in people with signs or symptoms of COVID-19 should be confirmed by a laboratory-based NAAT, a more sensitive test. Results from NAATs are considered the definitive result when there is a discrepancy between the antigen and NAAT test. For more information, see the Antigen Test Algorithm pdf icon[457 KB, 1 page].
People with positive results should isolate at home, in a campus-sponsored isolation room/floor/building, or if in a healthcare setting, be placed in an area with appropriate precautions. They should remain in isolation until they have met the criteria established by CDC for discontinuing home isolation or for discontinuing precautions in a healthcare setting. Positive test results should be promptly reported to public health authorities to allow for case investigation and contact tracing.
Testing of asymptomatic persons with recent known or suspected exposure to SARS-CoV-2
In partnership with the local health department, IHEs should consider how they will conduct case investigations and contact-trace known and potential close contacts of students, faculty and staff diagnosed with COVID-19. Identifying close contacts can help reduce the spread of SARS-CoV-2 when these close contacts quarantine themselves. Close contacts should be tested using a viral test immediately after being identified, and if negative, tested again in 5–7 days after last exposure or immediately if symptoms develop during quarantine (symptomatic close contacts should be tested regardless of vaccination status). If feasible, broader testing beyond close contacts may be done simultaneously with other strategies to control transmission of SARS-CoV-2 on campus.
The feasibility of identifying and testing close contacts may vary by IHE and the local health department. If individual contact tracing is not feasible, IHEs may consider testing all people who were in the proximity of a person confirmed to have COVID-19 (e.g., those who shared communal spaces or bathrooms) or testing all individuals within a shared setting (e.g., testing all residents on a floor or an entire residence hall).
Testing to determine resolution of infection
Accumulating evidence supports ending isolation and precautions for persons with COVID-19 using a symptom-based strategy. Adults with more severe illness or who are immunocompromised may remain infectious up to 20 days or longer after symptom onset, so a test-based strategy could be considered in consultation with infectious disease experts for these people. For all others, a test-based strategy is no longer recommended except to discontinue isolation or precautions earlier than would occur under the symptom-based strategy.
Testing asymptomatic persons without known or suspected exposure to SARS-CoV-2 for early identification, isolation, and disease prevention
In an IHE setting, with frequent movement of faculty, staff, and students between the IHE and the community, entry screening at the start of each term combined with serial screening testing can help prevent or slow the spread of COVID-19. One study suggests that 96% of infections could be prevented from routine screening testing on college campuses in conjunction with extensive physical distancing and mandatory mask policies 4. Incentivizing voluntary testing may also be considered.
Prior to the beginning of each term, IHEs should implement entry screening testing for all students, including those who live off campus, and should consider implementing entry screening testing for faculty and staff. Individuals undergoing entry screening testing should be quarantined pending return of test results. In screening settings where antigen tests are used, confirmatory laboratory-based NAAT testing is recommended for individuals who test positive. For interpretation of screening test results, please see the Antigen Test Algorithm pdf icon[457 KB, 1 page].
In the context of low community transmission of SARS-CoV-2 (Table 2), entry screening alone prior to the beginning of each term may be sufficient. In the context of moderate community transmission (Table 2), CDC recommends IHEs implement both universal entry screening and expanded serial screening testing at least weekly if sufficient testing capacity is available. In the context of substantial or high community transmission (Table 2) CDC recommends universal entry screening and expanded serial screening testing at least twice weekly if sufficient testing capacity is available. See Table 3.
Regardless of the level of community transmission, in the context of an outbreak at an IHE, CDC recommends initiation of increased serial screening testing among the IHE population (students, faculty, and staff), in addition to rapid case investigation and contact tracing, to reduce the spread of SARS-CoV-2. Testing a random sample of asymptomatic students, faculty, and staff is one strategy to increase the timeliness of outbreak detection 5. Additional testing could also be triggered by indications of increased community transmission (e.g., from positive testing results from wastewater surveillance).
If sufficient testing capacity is not available, expanded screening testing of specific groups (e.g., testing all students from a particular residential hall based on density of housing or if a cluster is detected) or less frequent serial testing may be considered to help rapidly identify and isolate infectious people. Pooled testing is another strategy that may reduce the burden of testing.
Testing strategies may also include increasing availability of testing for asymptomatic people who frequently come into contact with students, faculty, and staff (e.g., individuals who work in businesses that serve the IHE community), or who frequently visit campus (e.g., at community places of worship, public coffee shops, etc.), but are not formally affiliated with the IHE, in addition to current diagnostic and screening testing efforts.
CDC’s IHE testing recommendations are similar to testing guidelines set forth by the American College Health Associationexternal icon, which state that all students and IHE faculty and staff be tested for SARS-CoV-2 at least twice a week, with results available within 48 hours. As more people are vaccinated, SARS-CoV-2 testing priorities may shift to focus on unvaccinated faculty, staff, and students.
Table 2. Community Indicators at the County Level@
|Cumulative number of new cases per 100,000 persons within the last 7 days*||<10||10-49||50-99||≥100|
|Percentage of NAATs that are positive during the last 7 days†||<5%||5%-7.9%||8%-9.9%||≥10%|
Indicators should be calculated for counties or core based statistical areas, although in rural areas with low population density, multiple jurisdictions might need to be combined to make the indicators more useful for decision-making. The indicators listed can be found by county on CDC’s COVID Data Tracker Website under “county view.”
@ If the two indicators suggest different transmission levels, the higher level should be selected.
* Number of new cases in the county (or other administrative level) in the last 7 days divided by the population in the county (or other administrative level) and multiplying by 100,000.
† Number of positive tests in the county (or other administrative level) during the last 7 days divided by the total number of tests resulted in the county (or other administrative level) during the last 7 days. Calculating Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Laboratory Test Percent Positivity: CDC Methods and Considerations for Comparisons and Interpretation.
Table 3. Potential Actions based on Community Indicator Level
|Prevention Strategy||Low Transmission
|Implement universal entry screening|
|Implement universal entry screening and expanded screening testing at least weekly if there is sufficient testing capacity|
|Implement universal entry screening and expanded screening testing twice weekly if there is sufficient testing capacity|
Actions to Support Testing
IHE administrators should follow state and local laws as well as guidance from the Equal Employment Opportunity Commissionexternal icon when offering testing to faculty, staff, and students who are employed by the IHE. IHEs also should follow guidance from the U.S. Department of Education on the Family Educational Rights and Privacy Act (FERPA) and the Health Insurance Portability and Accountability Act (HIPAA)external icon and their applicability to students and COVID-19 contact tracing and testing.
Isolation and Quarantine
Students, faculty, or staff with SARS-CoV-2 infection should isolate, and their close contacts should quarantine and be tested immediately after being identified. If negative when first tested, close contacts should be tested again in 5–7 days after their last exposure or, regardless of vaccination status, immediately if they develop symptoms. Those who live on campus should remain on campus during isolation and quarantine periods, if possible. Isolating or quarantining on campus may prevent further spread to communities and to those at higher risk of severe illness and death but requires planning for healthcare as well as support services for affected students, faculty, or staff.
Isolation is used to separate people infected with SARS-CoV-2 from those who are not infected. People who are in isolation should stay home until it’s safe for them to be around others. At home, anyone sick or infected should separate from others, stay in a specific “sick room” or area, and use a separate bathroom (if available).
IHEs should refer symptomatic individuals for immediate testing and to an appropriate healthcare provider if needed. For symptomatic individuals, isolation should start at the onset of symptoms. Individuals should not wait for test results to begin isolation.
If well enough for self-care, individuals should follow CDC guidance for caring for themselves. IHEs can also encourage individuals to watch for emergency warning signs and seek emergency medical care if these symptoms occur.
For most people with COVID-19, isolation and precautions can generally be discontinued 10 days after symptom onset and resolution of fever for at least 24 hours, without the use of fever-reducing medications, and with improvement of other symptoms.
For people who never develop symptoms, isolation and other precautions can be discontinued 10 days after the date of specimen collection for their first positive RT-PCR test for SARS-CoV-2 RNA.
Quarantine is used to keep someone who might have been exposed to SARS-CoV-2 away from others. Quarantine helps prevent spread of disease that can occur before a person knows they are sick or if they are infected with the virus without experiencing symptoms. People in quarantine should stay home, separate themselves from others, monitor their health, and follow directions from their state or local health department.
Known close contacts of a positive individual, such as roommates, suitemates, those sharing an apartment, instructors with in-person contactand colleagues of faculty/staff should be quarantined and tested for SARS-CoV-2. All quarantined individuals should follow existing CDC guidance, stay in their current place of residence (in a separate room, if possible) or make alternative housing arrangements, and monitor their health for the prescribed quarantine period after last contact with a person who has COVID-19.
Close contacts should quarantine for 14 days whether initial test result is positive or negative. Based on local circumstances and resources, options to shorten quarantine might include a 10-day quarantine or a 7-day quarantine combined with testing.
IHE administrators and healthcare providers should provide options to immediately separate students with COVID-19 and their close contacts by providing virtual learning options and self-isolation and self-quarantine rooms in residence halls or other housing facilities. Students should receive support managing COVID-19 symptoms, including medical care when necessary, as well as support managing emotional issues related to isolation or quarantine and the provision of alternative food service arrangements for those who live on campus.
For Faculty and Staff
IHE administrators should offer alternative teaching and work-from-home options for faculty, instructors, and staff who have COVID-19 or have been identified as a close contact, provided that they are well enough to continue working remotely. IHEs should consider implementing flexible sick leave and supportive policies and practices.
IHEs should implement communications campaigns using behavior-based and actionable strategies to increase prevention, testing, isolation, and quarantine. Communication plans for prevention should also include any relevant guidance on returning to campus after traveling (e.g., holiday breaks, sports-related travel, etc.).
In accordance with state, territorial, tribal, and local laws and regulations, IHEs should make a plan to communicate with individuals who have a confirmed COVID-19 diagnosis and those suspected of having COVID-19, as well as to communicate relevant information about known cases to other students, faculty, and staff in a way that protects personally identifiable information. If privacy can be ensured, the IHE may also want to be made aware of SARS-CoV-2 test results and symptoms through voluntary reporting by their students, faculty, and staff.
Testing of Previously Positive Individuals
CDC does NOT recommend retesting individuals who do not have symptoms and had a positive test within 3 months of the initial testing date. Data currently suggest that some individuals who were previously infected with SARS-CoV-2 will continue to test positive due to residual virus material but are unlikely to be infectious.
Vaccination and SARS-CoV-2 Testing
Prior receipt of a COVID-19 vaccine will not affect the results of SARS-CoV-2 viral tests (NAAT or antigen). Antibody testing is not currently recommended to assess for immunity to SARS-CoV-2 following COVID-19 vaccination or to assess the need for vaccination in an unvaccinated person. Guidance on testing strategies for individuals who are fully vaccinated will be provided once more information is available.
Health Equity in SARS-CoV-2 Testing
CDC’s COVID-19 Response Health Equity Strategy outlines a plan to reduce the impact of COVID-19 among racial and ethnic minority populations and other population groups (e.g., essential and frontline workers, people living in rural or frontier areas) who have experienced a disproportionate burden of COVID-19. Efforts should be made to address barriers that might overtly or inadvertently create inequalities in testing. IHEs should work to ensure equitable access to testing among all students, faculty, and staff, particularly staff who are considered “essential.” Upon the return of a positive test result, IHEs should work to ensure that actions taken for students, faculty, and staff (e.g., isolation on or off campus, work-from-home, and virtual learning options) are implemented in a manner that considers health equity and ensures equitable access to resources and support services.
In addition, completeness of race and ethnicity data is an important factor in understanding the impact of COVID-19 on racial and ethnic minority populations. The U.S. Department of Health and Human Services has required laboratories and testing facilities to reportexternal icon race and ethnicity data to health departments, in addition to other data elements, for individuals tested for SARS-CoV-2 or diagnosed with COVID-19. Healthcare providers and public health professionals need to ask and record race and ethnicity for anyone receiving a reportable test result and ensure these data are reported with the person’s test results in order to facilitate understanding the impact of COVID-19 on racial and ethnic minority populations.
- The CDC Field Epidemiology Manual: Community and Congregate Settings. https://www.cdc.gov/eis/field-epi-manual/chapters/community-settings.html
- Fox MD, Bailey DC, Seamon MD, Miranda ML. Response to a COVID-19 Outbreak on a University Campus — Indiana, August 2020. MMWR Morb Mortal Wkly Rep 2021;70:118–122. DOI: http://dx.doi.org/10.15585/mmwr.mm7004a3external icon.
- Honein MA, Christie A, Rose DA, et al. Summary of Guidance for Public Health Strategies to Address High Levels of Community Transmission of SARS-CoV-2 and Related Deaths, December 2020. MMWR Morb Mortal Wkly Rep 2020;69:1860-1867. DOI: http://dx.doi.org/10.15585/mmwr.mm6949e2external icon
- Losina E, Leifer V, Millham L, et al. College campuses and COVID-19 mitigation: clinical and economic value. Ann Intern Med. September 2020. DOI :10.7326/M20-6558.
- National Academies of Sciences, Engineering, and Medicine 2020. COVID-19 Testing Strategies for Colleges and Universities. Washington, DC: The National Academies Press. https://doi.org/10.17226/26005external icon.