Author: COVID-19 NEWS

The U.S. Centers for Disease Control and Prevention (CDC) is working closely with international partners to respond to the coronavirus disease 2019 (COVID-19) pandemic. CDC provides technical assistance to help other countries increase their ability to prevent, detect, and respond to health threats, including COVID-19.
This document is provided by CDC and is intended for use in non-US healthcare settings.

This slide deck is a reference for content on this page and can be used for training

1. Overview
This document provides guidance on the identification or screening of healthcare workers1 and inpatients with symptoms of suspected COVID-19. Rational, requirements, and considerations will be discussed for three broad case identification strategies:
Passive strategies: Reporting/alerts are initiated by the data source (e.g., healthcare worker or treating clinician) based on a known set of rules or regulations.
Enhanced passive strategies: Reporting/alerts are initiated by the data source with an added mechanism to prompt data collection, review, and/or reporting.
Active strategies: Reporting/alerts are initiated by the centralized health authority (e.g., Ministry of Health, facility infection preventionist, facility administration) using a known set of rules or regulations.
Additional guidance on managing visitors to healthcare facilities and triage of suspected COVID-19 patients in non-US healthcare settings is also available.
While, epidemiologic, virologic, and modeling reports support the possibility of SARS-CoV-2, the virus that causes COVID-19,  transmission from persons who are presymptomatic (SARS-CoV-2 detected before symptom onset) or asymptomatic (SARS-CoV-2 detected but symptoms never develop), critical knowledge gaps remain regarding the benefit of routine or repeated screening of healthcare workers and inpatients without symptoms for prevention of COVID-19 spread within health facilities outside of an outbreak response scenario.2 Therefore, discussion around optimal testing strategies for the identification of healthcare workers with presymptomatic and asymptomatic SARS-CoV-2 infection are outside the scope of this guidance.
 2. Signs and Symptoms Consistent with COVID-19
Presenting signs and symptoms of COVID-19 vary, limiting the definition of a generalizable set of characteristic signs and symptoms for COVID-19. At best, current evidence suggests substantial variability ranging from mild to severe and based on only partially described patient-level factors. The WHO interim guidance for clinical management of COVID-19external icon provides the following summary of published COVID-19 symptom descriptions and observed frequency (see box):

Among persons who develop symptoms, most experience fever (83%–99%), cough (59%–82%), fatigue (44%–70%), anorexia (40%–84%), shortness of breath (31%–40%), and myalgias (11%–35%). Other non-specific symptoms, such as sore throat, nasal congestion, headache, diarrhea, nausea, and vomiting, have also been reported. Loss of smell (anosmia) or loss of taste (ageusia) preceding the onset of respiratory symptoms has also been reported.
Older people and immunosuppressed patients in particular may present with atypical symptoms such as fatigue, reduced alertness, reduced mobility, diarrhea, loss of appetite, delirium, and absence of fever.
Symptoms such as dyspnea, fever, gastrointestinal (GI) symptoms or fatigue due to physiologic adaptations in pregnant women, adverse pregnancy events, or other diseases such as malaria, may overlap with symptoms of COVID-19.
Children might not have reported fever or cough as frequently as adults.

Given these limitations, facilities should define a standardized set of signs and symptoms (e.g., fever and/or cough/shortness of breath) to screen healthcare workers and patients for suspected COVID-19. A high level of suspicion is critical to ensure cases do not go unrecognized due to a substantial proportion of patients and healthcare workers presenting with atypical or minimal symptoms.
3. General Best Practices
In addition to a specific strategy for the identification of suspected COVID-19 cases, there are general best practices that will improve both healthcare worker and inpatient COVID-19 screening. Some examples include:
Monitor and Manage Ill and Exposed Healthcare Workers
Facilities and organizations providing healthcare should implement sick leave policies for healthcare workers that are non-punitive, flexible, and consistent with public health guidance.
Movement and monitoring decisions for healthcare workers with exposure to COVID-19 should be made in consultation with public health authorities.
Train and Educate Healthcare Workers
Provide healthcare workers with job- or task-specific education and training on identifying and preventing transmission of infectious agents, including refresher training.
Ensure that healthcare workers are educated, trained, and have practiced the appropriate use of personal protective equipment (PPE) prior to caring for a patient.
Provide job-aids and up-to-date reference materials.
Encourage and support a high index of suspicion in healthcare workers regarding suspect COVID-19 cases.
Establish Reporting within and between Healthcare Facilities and to Public Health Authorities
Implement mechanisms and policies that promote situational awareness for facility staff about confirmed or suspected COVID-19 patients and facility plans for response, including:
Infection control
Healthcare epidemiology
Facility leadership
Occupational health
Clinical laboratory
Frontline staff

Communicate and collaborate with public health authorities.
Communicate information about confirmed or suspected COVID-19 patients to appropriate personnel before transferring to other departments in the facility and to other healthcare facilities.
4. Surveillance Capacities
Facility-based surveillance for healthcare-associated infections (HAIs), including infections in healthcare workers and inpatients, is one of the WHO’s eight core components of infection prevention and control (IPC)external icon.  While surveillance is a critical component of providing safe healthcare, it is important to recognize that it requires expertise, good quality data, and an established IPC program and thus, may require time to set up. For this reason, during public health emergency response, healthcare facilities are encouraged to initially implement facility-based, suspect COVID-19 patient case finding (surveillance) that is feasible with existing surveillance capacities.
Health facility surveillance capacity varies greatly even within health systems.  A realistic appraisal of capacity can help identify the best strategy for a given context.  A general description of surveillance capacities based on existing HAI surveillance activity is provided for guidance.
5. Identification of Healthcare workers with suspected COVID-19
Objective:  Prevent exposure of at-risk patients and staff to symptomatic COVID-19 positive healthcare workers.

Figure: Passive identification of healthcare workers with suspected COVID-19

Passive strategy
All healthcare workers self-assess for fever and/or a defined set of newly present symptoms indicative of COVID-19.  If fever or respiratory symptoms are present, healthcare workers:
Remotely report this information4
Do not go to their health facility
Are provided with immediate medical assessment and follow-up actions
Rationale:
Establishes mechanisms for the identification of healthcare workers at increased likelihood of infection with minimal resource requirements.
Requirements:
List of symptoms and thermometer for self-assessment.
Staff and mechanism (e.g., telephone line) for remote reporting of fever and/or presence of symptoms consistent with COVID-19. Ideally this system is always available for quick medical assessment. If reporting system is not available, symptomatic healthcare workers should not report to their facility until they can be evaluated.
Decision algorithms for response to healthcare worker reports and the results of secondary assessment.
Standardized medical assessment and movement and monitoring forms.
Considerations:
Adherence is highly dependent on healthcare worker motivation and appropriate self-assessment of risk.
Can result in reduction in work force, particularly among some critical staffing categories.
Provision of paid sick leave/compensation for all healthcare workers not allowed to work is often critical for success, requiring substantial resources.

Figure: Enhanced passive identification of healthcare workers with suspected COVID-19

Enhanced passive strategy
In addition to passive strategy, establish a plan to remind or prompt workers to self-assess for symptoms consistent with COVID-19. Common reminders include automated text messages or phone calls.
Rationale:
Evidence suggests that simple automatic reminders can increase adherence.
Requirements:
All requirements of Passive Strategy
Automated (e.g., mass texting service) or manual system (e.g., direct messaging or phone calls) to contact healthcare workers as prompt for self-assessment
Requirements (Automated System):
Mass Text Messaging Services capable of sending text messages to groups of people simultaneously. Mass Text Messaging Services are sometimes provided by independent internet-based service companies or are sometimes provided by cellular service providers.
Database of contacts (i.e., healthcare workers under monitoring). In addition to contact number, database fields may include name, position, work unit/area, and monitoring end date.
An effective and informative text message including frequency of messaging, timing of delivery, and any interactivity of interventions5.
Requirements (Manual System):
Database of contacts (i.e., healthcare workers under monitoring). Because of the effort required in manual systems, this database should be carefully targeted to minimize workload and maximize benefit. Considerations for targeting might include:
Documented COVID-19 exposure
Serving a population at high-risk for severe illness from COVID-19
Serving a population at increased risk of being COVID-19 positive cases

Staff available to contact monitored healthcare workers with reminders.
Phone and phone credit to support messaging and or calls.
Considerations:
Same as Passive Strategy
Funding may be required to support bulk text messaging

Figure: Active identification of healthcare workers with suspected COVID-19

Active strategy
All healthcare workers present for in-person evaluation of symptoms and fever prior to each shift. If symptoms consistent of COVID-19 are reported or observed, healthcare workers are provided with immediate follow-up actions.
Remote active strategy
All healthcare workers report (e.g., by call or text) the absence or presence of symptoms consistent with COVID-19 remotely each day. Staff that fail to report or report symptoms are followed up.
Rationale:
While there is limited evidence for the benefit of active healthcare worker monitoring, active strategies will theoretically result in increased healthcare worker adherence to self-evaluation of symptoms, thus enhancing patient and healthcare worker protection.
Requirements (Active strategy):
All requirements of Passive Strategy
Dedicated staff to evaluate healthcare workers before their shift (active) or respond and monitor healthcare worker reports
Physical area for staff evaluations that will allow recommended social distancing (i.e., at least one meter according to WHO recommendations (CDC recommendation is at least 6 feet (1.8 meters)) and includes adequate hand hygiene stations (soap and running water or alcohol-based hand rub)
No touch thermometers
Implementation plan that includes a method to ensure that staff present at a given place for pre-shift evaluation
Accountability system to ensure all healthcare workers have been evaluated (e.g., work slip sign-off)
Requirements (Remote Active Strategy):
All requirements of Passive Strategy
Accountability system to ensure all healthcare workers report in remotely prior to their work shift
Considerations:
Same as Passive Strategy.
Active monitoring of healthcare workers can be highly resource-intensive. There is limited evidence of increased effectiveness in prevention of nosocomial transmission beyond passive strategies.
Acceptance by staff can be limited by perceptions of mistrust in ability to monitor and appropriately report symptoms.
Active monitoring can decrease the likelihood that healthcare workers self-monitor signs and symptoms. Ideally, healthcare workers are checking their own temperature and symptoms and will not present if not indicated. Any action that weakens self-monitoring should be implemented with caution.
To decrease workload, and if accountability can be maintained, the following can be delegated to unit/immediate supervisors (e.g., head/charge nurses, department heads):
Responsibility for receiving symptom/temperature reports
Monitoring staff compliance for the remote active strategy

6. Identification of Inpatients with suspected COVID-19
The development of acute respiratory infection and healthcare-associated pneumonia are common complications of hospitalization. However, it is important that clinicians maintain a high level of suspicion for COVID-19 when there is a compatible presentation. Because healthcare facilities often represent a gathering of individuals at higher risk of infection and adverse outcomes, the potential for outbreaks and harm to patients requires special effort to ensure any inpatient COVID-19 cases are identified.
A goal of identifying inpatients with suspected COVID-19 is to guide IPC strategies to prevent or limit transmission in healthcare setting.  See interim WHO guidance on infection prevention and control during health care when COVID-19 is suspectedexternal icon.

Figure: Passive strategy for identification of inpatients with suspected COVID-19

Passive Strategy:
Clinicians are kept informed6 on:
Clinicians are also made aware of what to do if they suspect COVID-19 in a hospitalized patient, including isolation precautions, PPE use, reporting/informing IPC focal point at the facility and public health authorities, and how to obtain testing, if available.
Recommended Surveillance Capacity Level:
Applicable at all HAI surveillance capacity levels (i.e., very low to high)
Rationale:
Minimal disruption of existing clinical practice and no requirement for standardized data collection or form completion. Strategy seeks to encourage recognition and reporting by astute clinicians.
Requirements:
Regular and up-to-date educational materials/job aids provided to and accessible by clinicians
COVID-19 case definitions
Standard operating procedure (SOP) for response to identified suspect case patients (e.g., isolation, cohorting, PPE).
Acceptable reporting/communication channels to hospital administration and public health authorities
Considerations:
Strategy is dependent on participation and skill of available clinicians and an understanding of local epidemiology and clinical presentation of COVID-19, which may differ in different populations.
Limited access to diagnostic testing will complicate this effort with the most conservative strategy being to treat all suspect cases as confirmed cases (empirical case determination) – potentially wasting resources, and if cases are cohorted, mixing positive and negative patients for extended periods.
The degree of resource waste and case patient mixing will depend on the accuracy of empirical case determination.
Supporting empirical case determination through clinician education and job aids (as described) can help improve accuracy of clinical diagnosis of COVID-19.

Figure: Enhanced passive strategy for identification of inpatients with suspected COVID-19

Enhanced Passive Strategy:
Enhancement of the passive strategy can be achieved through establishing systems that prompt or require clinicians to regularly review all patients for suspected COVID-19. Example enhanced passive strategies might include:
Incorporating consideration of COVID-19 into sign-out reporting
Requiring units to provide a daily clinician-generated list of suspected cases, including if there are zero cases
Sending specific daily requests to clinicians to report and discuss encountered patients with symptoms consistent with COVID-19
Recommended Surveillance Capacity Level:
Applicable in most HAI surveillance capacity levels (very low to high)
Rationale:
Dialogue and accountability for case finding and reporting can improve empirical case determination, ensure patient evaluations are not missed, and help avoid clinician complacency over the long-term
Requirements:
All requirements of Passive Strategy
Strategy to prompt and/or ensure clinician review – requirements will depend on selected strategy
Considerations:
Effective strategies will be context specific and require thought and effort in design and implementation
May represent changes to current practice, which can limit acceptability

Figure: Active strategy for identification of inpatients with suspected COVID-19

Active Strategy:
Active case identification involves targeted data collection and review of patient information by groups specifically responsible for the identification of suspected COVID-19 cases. Examples of groups responsible for case identification and active case identification may include:
Ministries of Health
Sub-national/local public health authorities
Facility infection prevention and control teams
Recommended Surveillance Capacity Level:
High existing surveillance capacity or medium capacity with the provision of additional resources
Rationale:
Smaller more centralized team responsible for case identification can increase overall quality through dedicated training, improved engagement, limiting of competing priorities, and standardization of methods
Requirements:
Team with the information access, resources, and experience necessary for systematic review of patient information in order to appropriately apply standardized suspect case definitions
Group(s) with availability and responsibility for data collection, analysis/presentation, and information sharing
Group(s) with availability and responsibility for review of case-finding information with the authority and willingness to take appropriate action
Considerations:
Highly resource-intensive
Teams with the requisite skills can be difficult to build during outbreak response periods
Separates case finding activities from patient care activities, which can decrease acceptability and impact sustainability
Value of active inpatient case finding, especially the context of limited diagnostic testing, should be carefully considered

1. If HCP have recovered from SARS-CoV-2 infection but have a high-risk exposure within 3 months of their initial infection to a patient with SARS-CoV-2 infection, should they be restricted from work for 14 days after the exposure?
CDC has posted interim guidance for risk assessment and work restrictions for HCP with potential exposure to SARS-CoV-2. Because of their often extensive and close contact with people who are at high risk for severe illness, this guidance recommends a conservative approach to HCP monitoring and applying work restrictions to prevent transmission from potentially contagious HCP to patients, other HCP, and visitors. Review of currently available evidence suggests that most people do not become re-infected in the 3 months after SARS-CoV-2 infection. Testing of asymptomatic people during this 3-month period is complicated by the fact that some people have detectable virus from their prior infection during this period; a positive test during this period may more likely result from a prior infection rather than a new infection that poses risk for transmission.
In light of this, exposed HCP who are within 3 months of their initial infection, could continue to work, while monitoring for symptoms consistent with COVID-19 and following all recommended infection prevention and control practices (e.g., universal use of well-fitting source control). If symptoms develop, exposed HCP should be assessed and potentially tested for SARS-CoV-2, if an alternate etiology is not identified. Some facilities might still choose to institute work restrictions for asymptomatic HCP following a higher risk exposure, particularly if there is uncertainty about a prior infection or the durability of the person’s immune response. Examples could include:
HCP with underlying immunocompromising conditions (e.g., after organ transplantation) or who become immune compromised (e.g., receive chemotherapy) in the 3 months following SARS-Cov-2 infection who might  be at increased risk for reinfection. However, data on which specific conditions may lead to higher risk and the magnitude of risk are not available.
HCP for whom there is concern that their initial diagnosis of SARS-CoV-2 infection might have been based on a false positive test result (e.g., individual was asymptomatic, antigen test positive, and a confirmatory nucleic acid amplification test (NAAT) was not performed).
HCP for whom there is evidence that they were exposed to a novel SARS-CoV-2 variant for which the risk of reinfection might be higher (e.g., exposed to a person known to be infected with a novel variant).
CDC continues to actively investigate the frequency of reinfection and the circumstances surrounding these episodes, including the role that new variants might play in reinfection, and will adjust guidance as necessary as more information becomes available.
2. If HCP within 3 months of their initial infection develop symptoms consistent with COVID-19, should they be excluded from work and retested?
HCP within 3 months of a confirmed SARS-CoV-2 infection who develop symptoms consistent with COVID-19 should be evaluated to identify potential alternative etiologies for their symptoms. If an alternate etiology for the symptoms cannot be identified, they may need to be retested for SARS-CoV-2 infection with the understanding that a positive viral test could represent residual viral particles from the previous infection, rather than new infection. Decisions about the need for and duration of work exclusion should be based upon their suspected diagnosis (e.g., influenza, SARS-CoV-2 infection).
3. Do HCP within 3 months of their initial infection need to wear all recommended personal protective equipment (PPE) when caring for patients with suspected or confirmed SARS-CoV-2 infection? For example, if there are limited respirators, should respirators be prioritized for HCP who have not been previously infected?
Regardless of suspected or confirmed immunity, healthcare personnel should always wear all recommended PPE when caring for patients. In situations of PPE shortages, facilities should refer to CDC strategies for optimizing PPE supply. However, as with other infectious diseases (e.g., measles), allocation of available PPE should not be based on whether HCP have been previously infected or have evidence of immunity.
4. Should HCP within 3 months of their initial infection be preferentially assigned to care for patients with suspected or confirmed SARS-CoV-2 infection?
While individuals who have recovered from SARS-CoV-2 infection might develop some protective immunity, the duration and extent of such immunity are not known. Staffing decisions should be based on usual facility practices. Any HCP assigned to care for patients with suspected or confirmed SARS-CoV-2 infection, regardless of history of infection, should follow all recommended infection prevention and control practices when providing care. Guidance on mitigating staff shortages is also available.

CDC is responding to the COVID-19 pandemic by learning more about how the disease spreads and affects people and communities.
CDC’s Morbidity and Mortality Weekly Report publishes the results of COVID-19 outbreak investigations. CDC’s scientific journal Emerging Infectious Diseases has published dozens of studies by researchers studying COVID-19 since the pandemic began.

If you plan to travel internationally, you will need to get tested no more than 3 days before you travel by air into the United States (US) and show your negative result to the airline before you board your flight, or be prepared to show documentation of recovery (proof of a recent positive viral test and a letter from your healthcare provider or a public health official stating that you were cleared to travel).
On January 12, 2021, CDC announced an Order requiring all air passengers arriving to the US from a foreign country to get tested no more than 3 days before their flight departs and to present the negative result or documentation of having recovered from COVID-19 to the airline before boarding the flight. Air passengers will also be required to confirm that the information they present is true in the form of an attestation. This Order is effective as of 12:01am EST (5:01am GMT) on January 26, 2021.
For the full list of requirements and exemptions, please review the language in the Order.

alert icon

CDC recommends that you do not travel at this time. Delay travel and stay home to protect yourself and others from COVID-19. If you do travel, follow all CDC recommendations before, during, and after travel.

After You Travel Recommendations
Get tested 3-5 days after travel AND stay home and self-quarantine for 7 days after travel.
Even if you test negative, stay home and self-quarantine for the full 7 days.
If your test is positive, isolate yourself to protect others from getting infected.​​

​If you don’t get tested, it’s safest to stay home and self-quarantine for 10 days after travel.​
Avoid being around people who are at increased risk for severe illness for 14 days, whether you get tested or not.
Always ​follow state and local recommendations or requirements related to travel.

Frequently Asked Questions

General
Does this requirement apply to US citizens?
This Order applies to all air passengers, 2 years of age or older, traveling into the US, including US citizens and legal permanent residents.
Are foreign nationals no longer subject to Presidential Proclamation travel restrictions if they can show a negative test or documentation of recovery?
The CDC order does not replace the Presidential proclamations. Therefore, a negative test result for COVID-19 or documentation of having recovered from COVID-19 to the airline before boarding the flight does not exempt a foreign national from the travel restrictions outlined in the Presidential proclamations.
With specific exceptions, several Presidential proclamations suspend and limit entry into the United States, as immigrants or nonimmigrants, all aliens who were physically present within specific countries during the 14-day period preceding their entry or attempted entry into the United States.
For a full list of countries and links to the proclamations on the White House website, visit Travelers Prohibited from Entry to the United States.
Are US territories considered foreign countries for the purposes of this Order?
No, the Order to present a documentation of a negative COVID-19 test or recovery from COVID-19 does not apply to air passengers flying from a US territory to a US state.
US territories include American Samoa, Guam, the Northern Mariana Islands, the Commonwealth of Puerto Rico, and the US Virgin Islands.
If I fly from a US state or territory to another US state or territory, but have to transit through a foreign country, am I still required to get a test before the first flight?
If you booked an itinerary from a US state or territory to another US state or territory and the itinerary has you taking a connecting flight through a foreign country, you do not need to be tested. An example of this situation is an itinerary booked between the Northern Mariana Islands (a US territory) and the US mainland via Japan.
For information about what to do if you have a short trip to a foreign country from the US, see FAQ Can a test taken before departure from the US be used to return within the 3-day timeframe? How will testing requirements be handled for short trips?
Why does the Order specify 3 days rather than 72 hours? What is considered 3 days?
The 3-day period is the 3 days before the flight’s departure. The Order uses a 3-day timeframe instead of 72 hours to provide more flexibility to the traveler. By using a 3-day window, test validity does not depend on the time of the flight or the time of day that the test was administered.
For example, if a passenger’s flight is at 1pm on a Friday, the passenger could board with a negative test that was taken any time on the prior Tuesday or after.
What is an attestation?
An attestation is a statement, writing, entry, or other representation under 18 U.S.C. § 1001 that confirms that the information provided is true. 
Does this Order apply to land border crossings?
No, the requirements of this Order only apply to air travel into the US.
Who is checking to make sure that people have a negative test or documentation of recovery before they board a plane to the US?
The airline will confirm a COVID-19 negative test result or documentation of recovery for all passengers before boarding.
What types of SARS-CoV-2 test are acceptable under the Order?
Passengers must be tested with a viral test that could be either an antigen test or a nucleic acid amplification test (NAAT). Available NAATs for SARS-CoV-2 include reverse transcription polymerase chain reaction (RT-PCR), reverse transcription loop-mediated isothermal amplification (RT-LAMP), transcription-mediated amplification (TMA), nicking enzyme amplification reaction (NEAR), and helicase-dependent amplification (HDA). The test used must be authorized for use by the relevant national authority for the detection of SARS-CoV-2 in the country where the test is administered. A viral test conducted for U.S. Department of Defense (DOD) personnel, including DOD contractors, dependents, and other U.S. government employees, and tested by a DOD laboratory located in a foreign country also meets the requirements of the Order.
Can I get a rapid test?
Rapid tests are acceptable as long as they are a viral test acceptable under the Order.
Does an at home test qualify?
The Order requires a lab report to be presented to the airline or to public health officials upon request. A home specimen collection kit that is tested in a laboratory should meet the requirements, if such methods have been authorized by the country’s national health authorities. A viral test conducted for U.S. Department of Defense (DOD) personnel, including DOD contractors, dependents, and other U.S. government employees, and tested by a DOD laboratory located in a foreign country also meets the requirements of the Order.
What is a verifiable test result?
A verifiable test result must be in the form of written documentation (paper or electronic copy) of a laboratory test result. Testing must be performed using a viral test (NAAT or antigen), and negative results must be presented to the airline prior to boarding. The test result documentation must include information that identifies the person, a specimen collection date and the type of test. A negative test result must show test was done within the 3 days before the flight. A positive test result must show the test was done within the 3 months before the flight.
Does a negative test result or documentation of recovery need to be in English?
Airlines and other aircraft operators must be able to confirm the test result and review other required information, and should determine when translation is necessary for these purposes. Passengers whose documents are in a language other than English should check with their airline or aircraft operator before travel.
If a passenger has tested positive for COVID-19, and then tests negative, can that passenger travel?
Individuals with known or suspected COVID-19 should self-isolate and NOT travel until they have met CDC’s criteria for discontinuing isolation.
If a passenger has a negative test, but was a close contact of a known COVID case, can that passenger travel?
Individuals who have had close contact with a person with COVID-19 (i.e., who are considered exposed to COVID-19), should self-quarantine and NOT travel until they have met CDC criteria for discontinuing quarantine.
Do the requirements of this Order apply to diplomats and special visa holders?
Diplomats and special visa holders are not exempt from this Order.
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Passengers
What if I have had a COVID-19 vaccine or have tested positive for antibodies? Do I still need a negative COVID-19 test or documentation of recovery from COVID-19?
Yes, at this time all air passengers traveling to the US, regardless of vaccination or antibody status, are required to provide a negative COVID-19 test result or documentation of recovery.
When do I need to get a test to travel to the US and what kind of test do I need?
Get tested no more than 3 days before your flight to the US departs. Make sure to be tested with a viral test (NAAT or antigen test) to determine if you are currently infected with COVID-19. Also make sure that you receive your results before your flight departs and have documentation of your results to show the airline.
Do state and local governments in the US have separate testing requirements for air passengers?
Federal testing requirements must be met to board a plane to the US. Some state and local governments may have similar or more restrictive testing requirements for air passengers arriving in their jurisdictions. Always check and follow state and local recommendations or requirements related to travel in addition to federal requirements.
Can a test taken before departure from the US be used to return within the 3-day timeframe? How will testing requirements be handled for short trips?
If a trip is shorter than 3 days, a viral test taken in the United States can be used to fulfill the requirements of the Order as long as the specimen was taken no more than three days before the return flight to the US departs. If the return travel is delayed longer than 3 days after the test, the passenger will need to be retested before the return flight.
Travelers considering this option should additionally consider the availability of appropriate testing capacity at their destinations, and the time frame needed to obtain results, as a contingency when making plans for travel.
What if I recently recovered from COVID-19?
CDC does not recommend getting tested again in the three months after a positive viral test, as long as you do not have symptoms of COVID-19. If you have had a positive viral test in the past 3 months, and you have met the criteria to end isolation, you may travel instead with documentation of your positive viral test results and a letter from your healthcare provider or a public health official that states you have been cleared for travel. The positive test result and letter together are referred to as “documentation of recovery.”
A letter from your healthcare provider or a public health official that clears you to end isolation, e.g., to return to work or school, can be used to show you are cleared to travel, even if travel isn’t specifically mentioned in the letter.
What happens if I don’t take a test and want to travel to the US?
Air passengers traveling to the US are required to present a negative COVID-19 test result or documentation of recovery. Airlines must confirm the negative test result or documentation of recovery for all passengers before boarding. If a passenger chooses not to present a test result or documentation of recovery, the airline must deny boarding to the passenger.
What if I am overseas and can’t get tested before my flight?
Passengers should contact the airline regarding options for changing their departure date to allow time for a test, see if the airline has identified options for testing, or if there are options available for changing their flights to transit through a location where they can get tested before boarding their final flight to the United States.
I am unable to find a testing site that has a turnaround time of 1-3 days abroad. What should I do?
Travelers should consider the availability of appropriate testing capacity at their destinations, and the time frame needed to obtain results, as a contingency when making plans for travel.
For more information on where to obtain a test overseas, travelers should review the relevant U.S. Embassy websiteexternal icon. Travelers may need to consider a routing change to a different country or city in order to meet the testing requirement.
What happens if I test positive?
People should self-isolate and delay their travel if symptoms develop or a pre-departure test result is positive until they have recovered from COVID-19. Airlines must refuse to board anyone who does not present a negative test result for COVID-19 or documentation of recovery.
What kind of documentation of my test result or documentation of recovery do I need to present?
Before boarding a flight to the US, you will need to show a paper or electronic copy of your negative test result for review by the airline and for review upon request by public health officials after you arrive in the US.
If you are traveling with documentation of recovery, you must present paper or electronic copies of your positive test result and a signed letter, on official letterhead that contains the name, address, and phone number of a licensed healthcare provider or public health official, stating that you have been cleared to end isolation and therefore can travel. A letter that states that you have been cleared to end isolation to return to work or school is also acceptable. The letter does not have to specifically mention travel. The letter must be dated no more than 90 days ago.
Can I get an exemption or waiver to the testing requirement?
Exemptions may be granted on an extremely limited basis when emergency travel (like an emergency medical evacuation) must occur to preserve someone’s life, health against a serious danger, or physical safety and testing cannot be completed before travel.
Do passengers also need to have a copy of their attestation as well as the airline retaining it?
Passengers are only required to retain a paper or electronic copy of their negative test result or documentation of recovery for the entirety of their itinerary.  The attestation should be submitted to and retained by the airline or aircraft operator.
Should passengers retain proof of a negative test or documentation of recovery?
Yes, passengers must still retain a paper or electronic copy of the necessary documentation as federal public health officials may request to see these documents at the port of entry. State, territorial, tribal and/or local health departments in the United States may also request them under their own public health authorities.
If I am connecting through the US to another country, do I still need to get tested?
Yes.  Any flight entering the US, even for a connection, will require testing before departure.
If I have one or more connecting flights to the US, does the 3-day period apply to the first flight or the last one?
If your planned itinerary has you arriving via one or more connecting flights, your test can be taken within the 3 days before the departure of the first flight.
If you plan an itinerary incorporating 1 or more overnight stays en route to the US, and more than 3 days passes between the time of your test and your flight to the US, you will need to get retested before your flight to the US.
What happens if my flight (or first flight if itinerary includes connecting flights), is delayed and it goes over the 3-day limit for testing?
If the initial departing flight in your trip is delayed before departure, you will need to get re-tested if the delay causes your test to fall outside of the 3-day pre-departure testing period by more than 24 hours.
What if the 3-days times out due to a connecting flight delay?
If a connecting flight is delayed due to a situation outside of your control (e.g. weather or mechanical problem), you will need to get re-tested if the delay causes your test to fall outside of the 3-day pre-departure testing period by more than 48 hours.
For information about the 3-day period expiring during connecting flights see, If I have one or more connecting flights to the US, does the 3-day period apply to the first flight or the last one?
If I tested negative before my flight, do I need to get another test when I get to the US?
CDC recommends that travelers get tested 3-5 days after travel AND stay home or otherwise self-quarantine for 7 days after travel. Even if you test negative, stay home for the full 7 days. If you don’t get tested, it’s safest to stay home for 10 days. Always follow state and local recommendations or requirements related to travel.
All travelers (including those who have recovered from COVID-19) should remember to wear a mask, stay at least 6 feet apart from people who are not in your household, and wash their hands often with soap and water for at least 20 seconds after blowing their nose, coughing, or sneezing and before eating. Travelers should look for symptoms of COVID-19, and take your temperature if you feel sick. Anyone sick with symptoms of COVID-19 should self-isolate and delay further travel.
For more information, visit After You Travel.
Do I need to get a test before leaving the US?
At this time, CDC does not have a testing requirement for outbound travelers, but recommends that you get tested with a viral test (NAAT or antigen) 1-3 days before you travel internationally. Travelers should check with international destinations for their entry requirements.
What is the justification for letting people who recently recovered from COVID-19 travel without a negative test? What about reinfections?
People who have recovered from COVID-19 can continue to test positive for up to 3 months after their infection. CDC does not recommended retesting within 3 months after a person with COVID-19 first developed symptoms (or the date of their first positive viral diagnostic test if their infection was asymptomatic). Even if they have recovered from COVID-19, people who develop symptoms of COVID-19 should not travel and should seek care for testing and evaluation. This guidance may be updated as additional information about people who have recovered from COVID-19 becomes available.
Can CDC help me get a refund for travel expenses if I have to cancel or delay travel because of testing requirements for air passengers flying to the US?
CDC does not reimburse and is unable to help travelers get reimbursements for travel expenses as a result of canceled or delayed travel because of COVID-19 or testing requirements for air passengers flying to the US. While some companies may base their policies on CDC’s travel recommendations or requirements, each company establishes its own refund policies.
In some cases, trip cancellation insurance can protect your financial investment in a trip if you need to change your itinerary in the event of an international outbreak. Visit CDC’s Travelers’ Health website if you would like to learn more about travel insurance, including trip cancellation insurance.
Will CDC reimburse me for the cost of a COVID-19 test?
CDC is not able to reimburse travelers for COVID-19 testing fees. You may wish to contact your insurance provider or the location that provided your test about payment options.
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Aircraft Operators/Airlines/Crew FAQ
Does this order apply to all flights or just commercial flights?
This order applies to all flights, including private flights and general aviation aircraft (charter flights). Passengers traveling by air into the US are required to have proof of testing regardless of flight type.
Does the Order apply at pre-clearance ports?
Yes, the Order applies to all air passengers arriving from foreign countries.
What types of crew are exempt from the requirements of the Order? What types of travel by crew are exempt from the requirements of the Order?
Crew members on official duty assigned by the air carrier or operator that involves operation of aircraft, or the positioning of crew not operating the aircraft (i.e., on “deadhead” status), are exempt from the requirements of the Order provided their assignment is under an air carrier’s or operator’s occupational health and safety program.
Crew members traveling for training, commuting to or from work, or for business reasons not associated with the operation of the aircraft are not exempt from the testing requirement. Nor are crew traveling for personal reasons, such as leisure travel.
In a positioning or “deadhead” scenario, the crew member is on the “clock” and their time and movement are directed by the air carrier either into, from, or between operational assignments. On the other hand, “commuting” to and from locations where official duty begins and ends is considered personal travel. Crew would not be exempted from the Order when they are in a commuting status.
For the exemption to apply, the occupational health and safety program must follow industry standard protocols for the prevention of COVID-19 as set forth in relevant Safety Alerts for Operators (SAFO) pdf icon[PDF – 7 pages]external icon issued jointly by the Federal Aviation Administration (FAA) and CDC.
Other persons, such as maintenance personnel or contractors, may also be exempted if:
Their travel is for the purpose of operating the aircraft or ensuring the safety of flight operations; AND
The air carrier extends its occupational health and safety program to cover these individuals and ensures these persons follow the protocols contained in SAFO and CDC guidance; AND
The travel cannot be planned with sufficient time to enable the employee to take a COVID-19 test and obtain the results before the operational travel.
Air carriers or operators who assign their crew to travel in an official duty status (i.e., position or deadhead) on another air carrier should coordinate with that air carrier regarding their crew member’s eligibility for an exemption from testing.
CDC expects that air carriers or operators will determine whether their employee’s travel meets the requirements of the exemption. CDC also recommends that crew travel with an official statement (paper or electronic copy) from the carrier or operator that the employee’s travel meets the requirements of the exemption.
Operators of aircraft that are not operating under an air carrier’s or operator’s occupational health and safety program as described above are not exempt from the requirements of the Order.
Are federal law enforcement personnel exempt from the requirements of this Order?
Official travel by federal law enforcement officers is exempt from the requirements of the order if:
Federal law enforcement is carrying out a law enforcement function (e.g., for security purposes) on the aircraft; AND
the urgent need to travel does not allow time for testing
CDC expects that federal law enforcement agencies will determine whether their employees’ travel meets the requirements of the exemption.  CDC recommends that employees travel with a copy of their travel orders and a signed statement (paper or electronic) from their agency stating that the employee’s travel meets the requirements of the exemption.
Are U.S. Department of Defense personnel exempt from the testing requirement?
U.S. Department of Defense (DOD) personnel, which includes military personnel and civilian employees, dependents, contractors (including whole aircraft charter operators), and other U.S. government employees traveling on DOD aircraft or official DOD travel orders are exempt from the requirements of this Order, provided that such individuals are observing DOD testing requirements and recommendations described  in DOD’s Force Protection Guidance Supplement 14 – Department of Defense Guidance for Personnel Traveling During the Coronavirus Disease 2019 Pandemic (December 29, 2020) including its testing guidance.
DOD whole aircraft contract charter operators are also exempt from the requirements of CDC’s order when transporting DOD personnel including military personnel and civilian employees, dependents, other US Government employees, and contractors traveling under competent orders and observing DOD precautions.
CDC expects that DOD will determine what is considered “official travel orders” that would meet the requirements of this exemption. CDC recommends that DOD personnel traveling on non-DOD aircraft carry their official travel orders with them and present to air carrier/operator or public health authorities if needed. DOD personnel, including associated personnel who are traveling on non-DOD aircraft and not on official travel orders, remain subject to CDC’s testing order.
Where can airlines find the industry protocols that crew must follow to qualify for the exemption?
See Safety Alert for Operators pdf icon[PDF – 1 page]external icon for the relevant guidance issued jointly by the Federal Aviation Administration.
Will the US Government release the attestation form in other languages?
At this time, the attestation form is not available in other languages. Airlines and aircraft operators may use a third party to provide translations of the attestation. However, the airline or aircraft operator is responsible for ensuring the accuracy of any translation. The airline or aircraft operator may not shift this responsibility to a third party.
Can air carriers and operators create electronic/digital versions of the attestation? If electronic forms are used, what constitutes ‘signing’?
Air carriers and operators must ensure that the attestation is submitted by each passenger or an authorized representative before the flight’s departure. Boarding processes must incorporate a process by which either a physical signature, an authenticated digital signature, or an electronic system that uses unique identifiers to ensure the person filling out the electronic attestation form is the passenger or an authorized representative. For example, similar methods to those used to verify the identity of a passenger using a pre-boarding kiosk or an air carrier’s or operator’s website or app to obtain a boarding pass could be used to ensure that the passenger or authorized representative is the individual completing the attestation.
Alternatively, the air carrier or operator can use authenticated digital signatures (e.g., DocuSign) or an electronic version of an attestation that ensures only the individual passenger, or their authorized representative, has access to the data entry process (e.g., after keying in username/password or other identifying and/or itinerary-specific information as part of the pre-boarding or check in process).
Either method is acceptable if the air carrier or operator can be reasonably certain that the individual, or their authorized representative, is the only person that has access to the data entry process required to submit the attestation.
Can airlines/aircraft operators use an attestation only in a foreign language (rather than an English translation), so that the only version retained for two years would be in a foreign language?
Yes, airlines/aircraft operators may use and retain an attestation only in a foreign language.
The attestation may be difficult for our passengers to understand. Can the US Government or airlines provide a simpler version?
At this time, there is no alternative form of attestation. Airlines and aircraft operators must use the current attestation without alternation.
What should airlines and operators of private flights or general aviation aircraft do with passenger attestations?
Operators of private flights and general aviation aircraft must maintain passenger attestations for two years, per the Order.
Do airlines and operators of private flights or general aviation aircraft need to keep copies of passenger test results?
No, passengers must show a copy of their test results to airline employees or the aircraft operator before boarding, but the airline or aircraft operator does not need to retain copies of test results.
Is there specific guidance operators of private flights or general aviation aircraft need to follow if they want to transport a patient who has tested positive, or exposed contacts?
For transporting patients that have tested positive for COVID-19, operators must adhere to  CDC’s Interim Guidance for Transporting or Arranging Transportation by Air into, from, or within the United States of People with COVID-19 or COVID-19 Exposure.
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This document is intended to provide guidance on the appropriate use of testing among healthcare personnel and does not dictate the determination of payment decisions or insurance coverage of such testing, except as may be otherwise referenced (or prescribed) by another entity or federal or state agency.
The CDC recommendations for SARS-CoV-2 testing have been developed based on what is currently known about COVID-19 and are subject to change as additional information becomes available.

Summary of Recent Changes

Added a recommendation from the CDC Decision Memo that asymptomatic people who have recovered from SARS-CoV-2 infection may not need to undergo repeat testing or quarantine in the case of another SARS-CoV-2 exposure within 3 months of their initial diagnosis.

Key Points
Testing of healthcare personnel (HCP) can be considered in four situations:
Testing HCP with signs or symptoms consistent with COVID-19
Testing asymptomatic HCP with known or suspected exposure to SARS-CoV-2
Testing asymptomatic HCP without known or suspected exposure to SARS-CoV-2 as part of expanded screening
Testing HCP who have been diagnosed with SARS-CoV-2 infection to determine when they are no longer infectious
Introduction
This document provides a summary of considerations and current Centers for Disease Control and Prevention (CDC) recommendations regarding testing HCP for SARS-CoV-2. This document does not apply to individuals who do not meet the definition of HCP as defined below.
Testing should be prioritized for HCP with signs and symptoms consistent with COVID-19 and HCP with high-risk exposures to SARS-CoV-2 as described below.
Viral tests (authorized nucleic acid or antigen detection assays) are recommended to diagnose acute infection. Testing practices should aim for rapid turnaround times (i.e., less than 24 hours) in order to facilitate effective interventions. Testing the same individual more than once in a 24-hour period is not recommended.
HCP undergoing testing should receive clear information on:
the purpose of the test
the reliability of the test and any limitations associated with the test
who will pay for the test and how the test will be performed
how to interpret results and any next steps related to the results
who will receive the results
how the results may be used
any consequences for declining testing
Recommended practices to prevent occupational exposure to SARS-CoV-2 are described in the Interim Infection Prevention and Control Recommendations for Healthcare Personnel During the Coronavirus Disease 2019 (COVID-19) Pandemic.
Guidance for assessing HCP exposure risk and determining the need for work restrictions is available in the Interim U.S. Guidance for Risk Assessment and Work Restrictions for Healthcare Personnel with Potential Exposure to COVID-19
Testing HCP with signs or symptoms consistent with COVID-19
HCP with signs or symptoms of COVID-19 should be prioritized for SARS-CoV-2 testing.  Because HCP often have extensive and close contact to vulnerable populations, even mild signs or symptoms (e.g., sore throat) of possible COVID-19 should prompt consideration for testing.  Clinicians should use their judgment to determine if HCP have signs or symptoms compatible with COVID-19 and whether HCP should be tested.
CDC recommends using authorized nucleic acid or antigen detection assaysexternal icon that have received an FDA Emergency Use Authorization to test persons with symptoms when there is a concern of potential COVID-19. Tests should be used in accordance with the authorized labeling. Providers should be familiar with the tests’ performance characteristics and limitations.
Testing asymptomatic HCP with known or suspected exposure to SARS-CoV-2*
As part of community contact tracing efforts, viral testing is recommended for HCP who have had close contact with persons with SARS-CoV-2 infection in the community (including household contacts).
Exposures encountered by HCP are unlike those that might occur the community, and trained HCP generally use personal protective equipment (PPE) to reduce the risk of transmission. Because of this, assessment of HCP exposures should be performed as described in the Interim U.S. Guidance for Risk Assessment and Work Restrictions for Healthcare Personnel with Potential Exposure to COVID-19. Due to their often extensive and close contact with vulnerable individuals, this guidance recommends managing occupationally exposed HCP conservatively:
For certain exposures believed to pose a higher risk for transmission, CDC recommends that exposed HCP be excluded from work for 14 days following the exposure.
For other, lower risk exposures, HCP may continue to work; however, CDC recommends screening for symptoms prior to starting work each day and using source control measures as described in CDC’s infection control recommendations.
Similar to exposures in the community, testing initially and, if negative, again about 5-7 days post exposure could be considered for HCP with higher-risk exposures to more quickly identify pre-symptomatic or asymptomatic HCP who could contribute to SARS-CoV-2 transmission in the community. However, HCP with higher-risk exposures should still be excluded from work for 14 days, even if testing during this period does not identify SARS-CoV-2 infection. However, facilities with staffing shortages can refer to CDC’s staffing mitigation guidance, which describes considerations for allowing HCP with higher-risk exposures to work during their 14-day post-exposure period including options for shortening the quarantine period.  For HCP with lower-risk exposures, CDC continues to recommend symptom screening and source control measures while at work. As resources allow, facilities could consider testing HCP with lower-risk exposures for SARS-CoV-2 as described above.
Facilities that elect to perform post-exposure testing of HCP should be aware that testing is logistically challenging and has limitations. For example, testing only identifies the presence of virus at the time of the test. It is possible that HCP can test negative because they are very early in their infection when their sample is collected. In such situations, they could test positive later and transmit the virus to others; for this reason, repeat testing about 5-7 days after the exposure should be considered. Also, when there is SARS-CoV-2 transmission occurring in the community, positive tests in HCP do not necessarily indicate transmission due to exposures in the workplace.
If testing of exposed HCP is instituted, test results should be available rapidly (i.e., within 24 hours), and there should be a clear plan to respond to results. The Occupational Safety and Health Administration’s rules for Recording and Reporting Occupational Injuries and Illness (29 CFR part 1904external icon) should be consulted regarding requirements for certain employers to make and keep records of related cases of COVID-19.
In nursing homes, expanded viral testing of all HCP is recommended in response to an outbreak in the facility. Testing of all residents is also recommended in this situation.  See the Interim SARS-CoV-2 Testing Guidelines for Nursing Home Residents for more information.  An outbreak is defined as a new SARS-CoV-2 infection in any HCP or any nursing home-onset SARS-CoV-2 infection in a resident. Expanded viral testing includes initial testing of all HCP followed by repeat testing of all previously negative HCP, generally between every 3 days to 7 days, until the testing identifies no new cases of SARS-CoV-2 infection among residents or HCP for a period of at least 14 days since the most recent positive result. Expanded viral testing of HCP could also be considered in other healthcare settings in some situations (e.g., when multiple instances of SARS-CoV-2 transmission are identified among patients or HCP).
*Asymptomatic HCP who have recovered from SARS-CoV-2 infection may not need to undergo repeat testing or quarantine in the case of another SARS-CoV-2 exposure within 3 months of their initial diagnosis.  Additional information is available here.
Testing asymptomatic HCP without known or suspected exposure to SARS-CoV-2 as part of expanded screening
CDC continues to recommend that testing be prioritized for HCP with symptoms consistent with COVID-19 and for asymptomatic HCP with known or suspected exposure to SARS-CoV-2 as described above.
Currently, testing asymptomatic HCP without known or suspected exposure to SARS-CoV-2 is recommended for HCP working in nursing homespdf iconexternal icon.
Testing asymptomatic HCP who do not work in nursing homes can be considered if resources are available; general guidance is available in the CDC Guidance for Expanded Screening Testing to Reduce Silent Spread of SARS-CoV-2. When contemplating such expanded testing in other healthcare settings, the following should be considered:
Testing asymptomatic HCP without known or suspected exposure to SARS-CoV-2 is most valuable when it is repeated frequently, especially if testing is conducted with a test with a lower sensitivity. Testing less frequently than once per week increases the risk of missing HCP who are infected between scheduled tests. Additional considerations about frequency and scope of testing are described in the CDC Guidance for Expanded Screening Testing to Reduce Silent Spread of SARS-CoV-2.
Facilities and health departments should consider the resources necessary to sustain these efforts before implementation. This might include an increased demand for confirmatory testing as false positives will occur, particularly when testing people who are less likely to be infected, such as HCP with no known exposure.
Testing might be most impactful when conducted on HCP who have regular close contact (within 6 feet) with large numbers of patients or who regularly care for persons with risk factors or medical conditions that increase the risk of severe illness.
As described in the section above, testing may not be recommended for asymptomatic HCP who have recovered from SARS-CoV-2 infection and are within 3 months of their initial diagnosis.
Testing to determine when HCP with SARS-CoV-2 infection are no longer infectious
A test-based strategy, which requires serial tests and improvement in symptoms, could be considered to allow HCP with SARS-CoV-2 to return to work earlier than the symptom-based strategy. However, in most cases, the test-based strategy results in prolonged work exclusion of HCP who continue to shed detectable SARS-CoV-2 RNA but are no longer infectious. A test-based strategy could also be considered for some HCP (e.g., severely immunocompromised) in consultation with local infectious diseases experts if concerns exist for the HCP being infectious for more than 20 days. In all other circumstances, the symptom-based strategy should be used to determine when HCP may return to work.
Definitions
Healthcare personnel (HCP): HCP refers to all paid and unpaid persons serving in healthcare settings who have the potential for direct or indirect exposure to patients or infectious materials, including body substances (e.g., blood, tissue, and specific body fluids); contaminated medical supplies, devices, and equipment; contaminated environmental surfaces; or contaminated air. HCP include, but are not limited to, emergency medical service personnel, nurses, nursing assistants, home health personnel, physicians, technicians, therapists, phlebotomists, pharmacists, students and trainees, contractual staff not employed by the healthcare facility, and persons not directly involved in patient care, but who could be exposed to infectious agents that can be transmitted in the healthcare setting (e.g., clerical, dietary, environmental services, laundry, security, engineering and facilities management, administrative, billing, and volunteer personnel). For this guidance, HCP does not include clinical laboratory personnel.
Healthcare settings refers to places where healthcare is delivered and include, but are not limited to, acute care facilities, long-term acute care facilities, inpatient rehabilitation facilities, nursing homes and assisted living facilities, home healthcare, vehicles where healthcare is delivered (e.g., mobile clinics), and outpatient facilities such as dialysis centers, physician offices, and others.
History of Updates
Updates as of December 14, 2020
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Background
Schools are an important part of the infrastructure of communities. They provide safe, supportive learning environments for students and employ teachers and other staff.1 Schools also provide critical services including school meal programs and social, physical, behavioral, and mental health services.1,2 Schools have indirect benefits to the community, including enabling parents, guardians, and caregivers to work.1,3 In the spring of 2020, all public kindergarten to grade 12 (K-12) schools in the United States closed for in-person instruction as a strategy to slow the spread of SARS-CoV-2. With the beginning of the fall term 2020, K-12 schools have variably used several models of instruction, including in-person, virtual, and hybrid models of instruction. Other countries have opened schools at varying points in the pandemic. Their experiences have contributed to our knowledge of the nature of SARS-CoV-2 transmission in schools and their surrounding communities.
COVID-19 among children and adolescents
Although children can be infected with SARS-CoV-2, can get sick from COVID-19, and can spread the virus to others, less than 10% of COVID-19 cases in the United States have been among children and adolescents aged 5–17 years (COVID Data Tracker). Compared with adults, children and adolescents who have COVID-19 are more commonly asymptomatic (never develop symptoms) or have mild, non-specific symptoms.4-11 Similar to adults with SARS-CoV-2 infections, children can spread SARS-CoV-2 to others when they don’t have symptoms or have mild, non-specific symptoms and thus might not know that they are infected and infectious. Children are less likely to develop severe illness or die from COVID-19.6,12-15 Nonetheless, 203 COVID-19 deaths among persons ages 0–18 have been reported to the National Center for Health Statistics through January 27, 2021. Although rates of severe outcomes from COVID-19 including mortality and hospitalization in school-aged children are low,16,17 health disparities in the occurrence of severe disease are evident in childhood. Hispanic ethnicity and Black race are associated with increased risks for hospitalization and ICU admission among children.16 Underlying medical conditions are also more commonly reported among children who are hospitalized or admitted to an ICU.16
Evidence from several studies suggests that children and adolescents may be less commonly infected with SARS-CoV-2 than adults.18-25 The proportion of persons infected among those exposed to SARS-CoV-2 is one measure of susceptibility to infection. The biological mechanisms underlying children’s decreased susceptibility to COVID-19 are unclear; proposed mechanisms include decreased expression of ACE2 receptors26 in the respiratory tract and age-related differences in immune response to SARS-CoV-2.14,27,28 However, children generally have a lower risk of cumulative exposures and a lower likelihood of being tested compared with adults. For these reasons, it is difficult to determine how much of an observed difference in detected infection rates between children and adults may be attributed to biological differences. Household transmission investigations and population screening studies during periods when schools are open for in-person instruction likely provide the strongest methods to evaluate risk of infection in children relative to adults. Some studies using such methods have demonstrated infection rates in children similar to those observed in adults.7 Other evidence suggests that differences in susceptibility between children and adults is not entirely due to lack of testing because children are more likely to be asymptomatic or show mild symptoms.5,18-20,22,29,30 For example, several population screening studies found lower incidences of SARS-CoV-2 infection among children under age 10 compared with adolescents or adults.18,21,24 Studies that traced household contacts and tested all contacts of index cases, regardless of symptom status, have also found lower rates of infection among children compared with adults.19,20,23,25 The questions of susceptibility and infectivity among children and adolescents require further study to explore potential explanations and mechanisms.
Younger children (

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Links with this icon indicate that you are leaving the CDC website.The Centers for Disease Control and Prevention (CDC) cannot attest to the accuracy of a non-federal website.
Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website.
You will be subject to the destination website’s privacy policy when you follow the link.
CDC is not responsible for Section 508 compliance (accessibility) on other federal or private website.

For more information on CDC’s web notification policies, see Website Disclaimers.