Interim US Guidance for Risk Assessment and Public Health Management of Persons with Potential Coronavirus Disease 2019 (COVID-19) Exposure in Travel-associated or Community Settings
Updated February 8, 2020
Revisions were made on February 8, 2020, to reflect the following:
- The term, “congregate settings” was defined and the definition of the term “social distancing” was updated.
- Updated guidance for exposure risk management was expanded to include
- Crews on passenger or cargo flights
- Contacts of asymptomatic people exposed to COVID-19
This interim guidance is effective as of February 3, 2020, and does not apply retrospectively to people who have been in China during the previous 14 days and are already in the United States.
CDC has provided separate guidance for healthcare settings.
CDC is closely monitoring an outbreak of respiratory illness caused by a novel (new) coronavirus (named by the World Health Organization as “COVID-19”) that was first detected in Wuhan, Hubei Province, China and which continues to expand. Chinese health officials have reported thousands of infections with COVID-19 in China, with the virus reportedly spreading from person-to-person in many parts of that country. Infections with COVID-19, most of them associated with travel from Wuhan, also are being reported in a growing number of international locations, including the United States. The first confirmed instance of person-to-person spread of COVID-19 in the United States with this virus was reported on January 30, 2020.
Coronaviruses are a large family of viruses that are common in humans and many different species of animals, including camels, cattle, cats, and bats. Rarely, animal coronaviruses can infect people and then spread between people such as with SARS, MERS, and likely now with COVID-19.
Current knowledge on how COVID-19 spreads is based on what is known about early COVID-19 cases and what is known about similar coronaviruses. Most often, spread from person-to-person happens during close exposure to a person infected with COVID-19. Person-to-person spread is thought to occur mainly via respiratory droplets produced when an infected person coughs, similar to how influenza viruses and other respiratory pathogens spread. These droplets can land in the mouths, noses, or eyes of people who are nearby or possibly be inhaled into the lungs. It is currently unclear if a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes.
CDC created this interim guidance to provide US public health authorities and other partners with a framework for assessing and managing risk of potential exposures to COVID-19 and implementing public health actions based on a person’s risk level and clinical presentation. Public health actions may include active monitoring or supervision of self-monitoring by public health authorities, or the application of movement restrictions, including isolation and quarantine, when needed to prevent the possible spread of COVID-19 in US communities. The recommendations in this guidance apply to US-bound travelers and people located in the United States who may have been exposed to COVID-19. CDC acknowledges that state and local jurisdictions may make risk management decisions that differ from those recommended here. However, a harmonized national approach will facilitate smooth coordination and minimize confusion. The guidance may be updated based on the evolving circumstances of the outbreak.
Definitions Used in this Guidance
Symptoms compatible with COVID-19 infection, for the purpose of these recommendations, include subjective or measured fever, cough, or difficulty breathing.
Self-observation means people should remain alert for subjective fever, cough, or difficulty breathing. If they feel feverish or develop cough or difficulty breathing during the self-observation period, they should take their temperature, limit contact with others, and seek health advice by telephone from a healthcare provider or their local health department to determine whether medical evaluation is needed.
Self-monitoring means people should monitor themselves for fever by taking their temperatures twice a day and remain alert for cough or difficulty breathing. Anyone on self-monitoring should be provided a plan for whom to contact if they develop fever, cough, or difficulty breathing during the self-monitoring period to determine whether medical evaluation is needed.
Self-monitoring with delegated supervision means, for certain occupational groups (e.g., some healthcare or laboratory personnel, airline crew members), self-monitoring with oversight by the appropriate occupational health or infection control program in coordination with the health department of jurisdiction. The occupational health or infection control personnel for the employing organization should establish points of contact between the organization, the self-monitoring personnel, and the local or state health departments with jurisdiction for the location where self-monitoring personnel will be during the self-monitoring period. This communication should result in agreement on a plan for medical evaluation of personnel who develop fever, cough, or difficulty breathing during the self-monitoring period. The plan should include instructions for notifying occupational health and the local public health authority, and transportation arrangements to a pre-designated hospital, if medically necessary, with advance notice if fever, cough, or difficulty breathing occur. The supervising organization should remain in contact with personnel through the self-monitoring period to oversee self-monitoring activities.
Self-monitoring with public health supervision means public health authorities assume the responsibility for oversight of self-monitoring for certain groups of people. CDC recommends that health departments establish initial communication with these people, provide a plan for self-monitoring and clear instructions for notifying the health department before the person seeks health care if they develop fever, cough, or difficulty breathing, and as resources allow, check in intermittently with these people over the course of the self-monitoring period. If travelers for whom public health supervision is recommended are identified at a US port of entry, CDC will notify state and territorial health departments with jurisdiction for the travelers’ final destinations.
Active monitoring means that the state or local public health authority assumes responsibility for establishing regular communication with potentially exposed people to assess for the presence of fever, cough, or difficulty breathing. For people with high-risk exposures, CDC recommends this communication occurs at least once each day. The mode of communication can be determined by the state or local public health authority and may include telephone calls or any electronic or internet-based means of communication.
Close contact is defined as in CDC’s Interim Guidance for Healthcare Professionals.
Public health orders are legally enforceable directives issued under the authority of a relevant federal, state, or local entity that, when applied to a person or group, may place restrictions on the activities undertaken by that person or group, potentially including movement restrictions or a requirement for monitoring by a public health authority, for the purposes of protecting the public’s health. Federal, state, or local public health orders may be issued to enforce isolation, quarantine or conditional release. The list of quarantinable communicable diseases for which federal public health orders are authorized is defined by Executive Order and includes “severe acute respiratory syndromes.” COVID-19 meets the definition for “severe acute respiratory syndromes” as set forth in Executive Order 13295, as amended by Executive Order 13375 and 13674, and, therefore, is a federally quarantinable communicable disease.
Isolation means the separation of a person or group of people known or reasonably believed to be infected with a communicable disease and potentially infectious from those who are not infected to prevent spread of the communicable disease. Isolation for public health purposes may be voluntary or compelled by federal, state, or local public health order.
Quarantine in general means the separation of a person or group of people reasonably believed to have been exposed to a communicable disease but not yet symptomatic, from others who have not been so exposed, to prevent the possible spread of the communicable disease.
Conditional release defines a set of legally enforceable conditions under which a person may be released from more stringent public health movement restrictions, such as quarantine in a secure facility. These conditions may include public health supervision through in-person visits by a health official or designee, telephone, or any electronic or internet-based means of communication as determined by the CDC Director or state or local health authority. A conditional release order may also place limits on travel or require restriction of a person’s movement outside their home.
Controlled travel involves exclusion from long-distance commercial conveyances (e.g., aircraft, ship, train, bus). For people subject to active monitoring, any long-distance travel should be coordinated with public health authorities to ensure uninterrupted monitoring. Air travel is not allowed by commercial flight but may occur via approved noncommercial air transport. CDC may use public health orders or federal public health travel restrictions to enforce controlled travel. CDC also has the authority to issue travel permits to define the conditions of interstate travel within the United States for people under certain public health orders or if other conditions are met.
Congregate settings are public places where close contact with others may occur. Congregate settings include settings such as shopping centers, movie theaters, stadiums, workplaces, and schools and other classroom settings.
Social distancing means remaining out of congregate settings, avoiding local public transportation (e.g., bus, subway, taxi, ride share), and maintaining distance (approximately 6 feet or 2 meters) from others. If social distancing is recommended, presence in congregate settings or use of local public transportation should only occur with approval of local or state health authorities.
Exposure Risk Categories
These categories should be considered interim and subject to change.
CDC has established the following exposure risk categories to help guide optimal public health management of people following potential SARS-CoV-2 exposure. These categories may not cover all potential exposure scenarios and should not replace an individual assessment of risk for the purpose of clinical decision making or individualized public health management. Any public health decisions that place restrictions on a person’s or group’s movements or impose specific monitoring requirements should be based on an assessment of risk for the person or group.
These risk levels apply to travel-associated and community settings. CDC has provided separate guidance for healthcare settings.
All exposures apply to the 14 days prior to assessment and recommendations apply until 14 days after the exposure event.
- Living in the same household as, being an intimate partner of, or providing care in a nonhealthcare setting (such as a home) for a person with symptomatic laboratory-confirmed COVID-19 infection without using recommended precautions for home care and home isolation
- The same risk assessment applies for the above-listed exposures to a person diagnosed clinically with COVID-19 infection outside of the United States who did not have laboratory testing.
- Travel from Hubei Province, China
- Close contact with a person with symptomatic laboratory-confirmed COVID-19 infection, and not having any exposures that meet a high-risk definition.
- The same risk assessment applies for close contact with a person diagnosed clinically with COVID-19 infection outside of the United States who did not have laboratory testing.
- On an aircraft, being seated within 6 feet (two meters) of a traveler with symptomatic laboratory-confirmed COVID-19 infection; this distance correlates approximately with 2 seats in each direction (refer to graphic above)
- Living in the same household as, an intimate partner of, or caring for a person in a nonhealthcare setting (such as a home) to a person with symptomatic laboratory-confirmed COVID-19 infection while consistently using recommended precautions for home care and home isolation
- Travel from mainland China outside Hubei Province AND not having any exposures that meet a high-risk definition
- Being in the same indoor environment (e.g., a classroom, a hospital waiting room) as a person with symptomatic laboratory-confirmed COVID-19 for a prolonged period of time but not meeting the definition of close contact
- On an aircraft, being seated within two rows of a traveler with symptomatic laboratory-confirmed COVID-19 but not within 6 feet (2 meters) (refer to graphic above) AND not having any exposures that meet a medium- or a high-risk definition (refer to graphic above)
No Identifiable Risk
- Interactions with a person with symptomatic laboratory-confirmed COVID-19 infection that do not meet any of the high-, medium- or low-risk conditions above, such as walking by the person or being briefly in the same room.
Recommendations for Exposure Risk Management
State and local authorities have primary jurisdiction for isolation and other public health orders within their respective jurisdictions. Federal public health authority primarily extends to international arrivals at ports of entry and to preventing interstate communicable disease threats.
CDC recognizes that decisions and criteria to use such public health measures may differ by jurisdiction. Consistent with principles of federalism, state and local jurisdictions may choose to make decisions about isolation, other public health orders, and monitoring that exceed those recommended in federal guidance.
The issuance of a public health order should be considered in the context of other less restrictive means that could accomplish the same public health goals. People under public health orders must be treated with respect, fairness, and compassion, and public health authorities should take steps to reduce the potential for stigma (e.g., through outreach to affected communities, public education campaigns). Considerable, thoughtful planning by public health authorities is needed to implement public health orders properly. Specifically, measures must be in place to provide shelter, food, water, and other necessities for people whose movement is restricted under public health orders, and to protect their dignity and privacy.
CDC’s recommendations for management of people with potential exposure to COVID-19, including monitoring and the application of travel or movement restrictions, are summarized in the Table below.
Additional recommendations in specific groups or settings are provided below.
Travelers from China
Travelers who have been in Hubei Province in the previous 14 days are reasonably believed to have a high risk of exposure to COVID-19 based on the scope and magnitude of the epidemic in that area. These travelers should be managed as having high-risk exposure.
For most travelers from areas of mainland China outside Hubei province, the exposure risk is unknown but believed to be lower than that from Hubei Province. Travelers with known exposures to a laboratory-confirmed case of COVID-19 should be managed according to the risk level as defined above. CDC has assigned a medium-risk level to travelers from mainland China outside Hubei Province who have no known high-risk exposures, with recommendations for public health management as provided in the Table below.
In general, these geographic exposures do not apply to travelers who only transit through an airport.
Crews on Passenger or Cargo Flights
Crew members who are based in the United States and who have been on layovers in mainland China outside Hubei Province within the previous 14 days, and who have no known exposure to persons with COVID-19, are assessed as low risk. These crew members should self-monitor under the supervision of the air carrier’s occupational health program in coordination with the health department of jurisdiction for the crew member’s residence in the United States. These crew members have no movement restrictions while in the United States and may continue to work on passenger or cargo flights as long as they remain asymptomatic. This recommendation is based on US-based air crews having limited interaction with the local population in China during a typical layover. If they develop fever, cough, or difficulty breathing, crew members should self-isolate and be excluded from work on flights immediately until cleared by public health authorities.
Crew members who are based in mainland China outside Hubei Province and who are in the United States for layovers are assessed as medium risk but may continue to work on passenger or cargo flights to and within the United States as long as they remain asymptomatic. These crew members should self-monitor under the supervision of the air carrier’s occupational health program. These crew members are also recommended to remain in their hotels, limit activities in public, practice social distancing, and avoid congregate settings while in the United States. The air carrier should coordinate with the health department of jurisdiction for the airport to establish a plan for managing crew members identified as symptomatic while in the United States. If they develop fever, cough, or difficulty breathing, crew members should self-isolate and be excluded from work on commercial flights immediately until cleared by public health authorities.
Crew members who are based outside the United States but not in mainland China are assessed as low risk. These crew members should be managed as for US-based crew members. In this circumstance, the US health department responsible for the airport has jurisdiction.
Air carriers have the authority to adopt occupational health policies for their own employees that exceed CDC recommendations.
People with low-risk exposures to SARS-CoV-2 are not restricted from public places, including workplaces, as long as they remain asymptomatic. Asymptomatic people with low-risk exposures are advised to self-observe until 14 days after their last potential exposure. Employers may choose to recommend that employees with low-risk exposures check their temperature to ensure they are still asymptomatic before arriving at the workplace.
Asymptomatic people with medium-risk exposures are recommended to avoid congregate settings, limit public activities, and practice social distancing. Employers may consider on a case-by-case basis, after consultation with state or local public health authorities, whether asymptomatic employees with medium-risk exposures may be able to work onsite. These decisions should take into account whether individual employees’ work responsibilities and locations allow them to remain separate from others during the entire work day. Asymptomatic employees with medium-risk exposures who are permitted to work onsite should not enter crowded workplace locations such as meeting spaces or cafeterias.
People with Confirmed COVID-19 and Symptomatic People Under Investigation for COVID-19
People with confirmed COVID-19 should remain in isolation, either at home or in a healthcare facility as determined by clinical status, until they are determined by state or local public health authorities in coordination with CDC to be no longer infectious. The location of isolation will be determined by public health authorities and isolation may be compelled by public health order, if necessary. Local or long-distance travel is permitted only by medical transport (e.g., ambulance or air medical transport) or private vehicle. Isolation and travel restrictions are removed upon determination by public health authorities that the person is no longer considered to be infectious. Symptomatic people who meet CDC’s definition of Persons Under Investigation (PUI) should be evaluated by healthcare providers in conjunction with local health authorities. PUIs awaiting results of rRT-PCR testing for COVID-19 should remain in isolation at home or in a healthcare facility until their test results are known. Depending on the clinical suspicion of COVID-19, PUIs for whom an initial rRT-PCR test is negative may be candidates for removal of any isolation and travel restrictions specific to symptomatic people, but any restrictions for asymptomatic people according to the assigned risk level should still apply. Management decisions of PUIs who are not tested should be made on a case-by-case basis, using available epidemiologic and clinical information, in conjunction with guidance in this document.
Contacts of Asymptomatic People Exposed to COVID-19
CDC does not recommend testing, symptom monitoring or special management for people exposed to asymptomatic people with potential exposures to SARS-CoV-2 (such as in a household), i.e., “contacts of contacts;” these people are not considered exposed to SARS-CoV-2.
Table: Summary of CDC Recommendations for Management of Persons with Potential COVID-19 Exposure by Risk Level and Symptoms
The public health actions recommended below apply to people who have been determined to have at least some risk for COVID-19. If people who are being managed as asymptomatic exposed people develop signs or symptoms compatible with COVID-19, they should be moved immediately into the symptomatic category and be managed according to the recommendations for symptomatic people in the applicable risk level.
Note: These risk levels apply to travel-associated and community settings. CDC will provide separate guidance for healthcare settings.
For recommendations for crew members on passenger or cargo flights, see section above.
|Risk Category||Movement Restrictions and Public Activities||Medical Evaluation||Travel|
|High risk||Immediate isolation.||Medical evaluation is recommended; diagnostic testing for COVID-19 should be guided by CDC’s PUI definition but is recommended for symptomatic people with a known high-risk exposure.
If medical evaluation is needed, it should occur with pre-notification to the receiving HCF and EMS, if EMS transport indicated, and with all recommended infection control precautions in place.
|Controlled; air travel only via air medical transport. Local travel is only allowed by medical transport (e.g., ambulance) or private vehicle while symptomatic person is wearing a face mask.|
|Medium risk||Immediate isolation.||Medical evaluation and care should be guided by clinical presentation; diagnostic testing for COVID-19
should be guided by CDC’s PUI definition
If medical evaluation is needed, it should occur with pre-notification to the receiving HCF and EMS, if EMS transport indicated, and with all recommended infection control precautions in place.
|Controlled; air travel only via approved air medical transport. Local travel is only allowed by medical transport (e.g., ambulance) or private vehicle while symptomatic person is wearing a face mask.|
|Low risk||Recommendation to avoid contact with others and public activities while symptomatic||Person should seek health advice to determine if medical evaluation is needed. If sought, medical evaluation and care should be guided by clinical presentation; diagnostic testing for COVID-19 should be guided by CDC’s PUI definition||Recommendation to not travel on long-distance commercial conveyances or local public transport while symptomatic|
|No Identifiable Risk2||No restriction||Routine medical care||No restriction|
|Risk Category||Movement Restrictions and Public Activities||Monitoring||Travel|
|High risk||Remain quarantined (voluntary or under public health orders on a case-by-case basis) in a location to be determined by public health authorities. No public activities.||Daily active monitoring||Controlled|
|Medium risk||To the extent possible, remain at home or in a comparable setting. Avoid congregate settings, limit public activities, and practice social distancing.||Travelers from mainland China outside Hubei Province with no known high-risk exposure: Self-monitoring with public health supervision
All others in this category: Active monitoring
|Recommendation to postpone additional long-distance travel after they reach their final destination. People who intend to travel should be advised that they might not be able to return if they become symptomatic during travel.|
|Low risk||No restriction||Self-observation||No restriction|
|No Identifiable Risk||No restriction||None||No restriction|
EMS = Emergency medical services
HCF = healthcare facility
PUI = Person Under Investigation for COVID-19
2No restrictions on travel, movement, or activities due to COVID-19 concerns; however, restrictions might be recommended if the person is known or reasonably believed to have another communicable disease that poses a public health threat if others are exposed in community or travel settings.