Interim Guidance on Risk Assessment and Management of Persons with Potential Ebolavirus or Marburgvirus Exposure

While guidance for post-arrival management of travelers from countries experiencing outbreaks applies only to Ebola disease and Marburg virus disease, recommendations for management of people with high-risk exposures apply to other viral hemorrhagic fevers* and should be followed regardless of where the exposure occurred (i.e., in an outbreak area overseas, another overseas location, or the United States).

*Lassa, Crimean Congo Hemorrhagic Fever (CCHF) and the South American Hemorrhagic Fevers (i.e., those caused by Junin, Machupo, Chapare, Guanarito and Sabia viruses). Note, for Crimean Congo Hemorrhagic Fever, management should continue until 14 days after the last known high-risk exposure.

There are currently no identified outbreaks of Ebola disease or Marburg virus disease.

Updates to this guidance

March 31, 2023

Revised recommendations to reduce burden to state, tribal, local, and territorial health departments

Generalized guidance to additionally apply to potential marburgvirus exposures

Removed specific guidance issued for the 2022 Sudan ebolavirus outbreak in Uganda

Key Points

  • CDC may recommend public health risk assessment and post-arrival management of travelers from countries with Ebola disease or Marburg virus disease (MVD) outbreaks to mitigate the risk of potential imported cases.
  • For U.S.-based healthcare or emergency response workers returning from Ebola disease or MVD outbreak areas, health departments may elect to delegate post-arrival management to the response workers’ sponsoring organizations. CDC has issued separate guidance for these organizations.

Who is this guidance for?

  • U.S. state, tribal, local, and territorial health departments

What is the purpose of this guidance?

  • To provide U.S. health departments with minimum expectations and guidance for post-arrival management of travelers arriving in their jurisdictions from countries with Ebola disease or MVD outbreaks.
  • To provide guidance for management of people with high-risk exposures who are located in or intend to travel to the United States.

Introduction

This guidance provides recommendations for post-arrival risk assessment and management of potentially exposed travelers as part of the domestic U.S. response to an Ebola disease or MVD outbreak occurring overseas. CDC may recommend such interventions based on an assessment of the risk of travel-associated importation to the United States and may provide outbreak-specific guidance for post-arrival management of travelers.

Definitions

Direct contact means physical contact with a person with Ebola disease or MVD (alive or dead) or with objects contaminated with the blood or other body fluids of a person with Ebola or Marburg (alive or dead) while not wearing recommended personal protective equipment (PPE) or while experiencing a breach in infection control precautions that could result in unprotected contact with the patient or their blood or other body fluids.

Ebola disease or MVD outbreak area means a geographic area where transmission of an ebolavirus or marburgvirus has occurred in the previous 42 days, as determined by surveillance conducted by national health authorities, non-governmental organizations (NGOs), and the World Health Organization (WHO). The list of designated outbreak areas for which CDC recommends post-arrival risk assessment and management of travelers will be maintained according to available information.

Isolation means the separation of a person or group of people, reasonably believed to be infected with a communicable disease and potentially infectious, from those who are not infected to prevent the spread of the communicable disease. Persons could be reasonably believed to be infected if they display the signs or symptoms of the communicable disease of concern and there is some epidemiologic reason to believe that an exposure had occurred. Isolation for public health purposes may be voluntary or compelled by a federal, state, tribal, local, or territorial public health order.

Monitoring period refers to the time from arrival in the United States until 21 days after the person left a designated outbreak area.

Public health orders are legally enforceable directives issued under the authority of a relevant federal, state, tribal, local, or territorial 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 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 viral hemorrhagic fevers such as Ebola disease and MVD.

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 infectious, from others who have not been so exposed, to prevent the possible spread of the communicable disease.

Suspect case refers to the combination of signs and symptoms compatible with Ebola disease or MVD AND an epidemiological risk factor within 21 days before the onset of symptoms, before confirmatory testing occurs. See additional information for Ebola disease or MVD.

International Air Passenger Contact Information

If post-arrival risk assessment and management are recommended, CDC will obtain contact information for travelers arriving from countries or areas with Ebola disease or MVD outbreaks and provide it electronically to health departments through established secure mechanisms.

Risk Assessment and Post-arrival Management

If post-arrival risk assessment and management are recommended, health departments should establish contact with travelers arriving in their jurisdictions from a country with an Ebola disease or MVD outbreak to conduct an initial assessment of exposure risk, provide health education, conduct symptom monitoring (as described below), and track overall success in monitoring incoming travelers, according to resources available in the jurisdiction. The initial assessment should occur as soon as feasible, ideally within 24 hours of receiving CDC’s notification of the traveler’s arrival. A summary of these recommendations is provided in the table below.

CDC has issued separate guidance for organizations sending U.S.-based healthcare or emergency response workers to areas with Ebola disease or MVD outbreaks, including recommendations for a structured pre-departure assessment and post-arrival management. Health departments that maintain contact with these organizations may elect to accept risk assessment and/or monitoring of these workers by the sponsoring organization; they may also request updates from the sponsoring organization or assume direct responsibility for risk assessment and/or monitoring of these workers.

Designated Ebola Disease or Marburg Virus Disease Outbreak Areas

There are currently no designated Ebola disease or MVD outbreak areas for which post-arrival traveler management is recommended.

High-risk Exposure Definition
  • Percutaneous (i.e., piercing the skin), mucous membrane (e.g., eye, nose or mouth), or skin contact with blood or other body fluids1 of a person with known or suspected Ebola disease or Marburg virus disease (MVD)
  • Direct contact with person who has known or suspected Ebola disease or MVD
  • Providing health care to a patient with known or suspected Ebola disease or MVD without use of recommended personal protective equipment (PPE)2, or experiencing a breach in infection control precautions that results in the potential for percutaneous, mucous membrane, or skin contact with the blood or other body fluids of a patient with Ebola disease or MVD while working in an Ebola disease or MVD treatment unit or associated facility (e.g., laboratory) or while taking care of a patient with Ebola disease or MVD
  • Direct contact with, or the occurrence of a breach in infection control precautions while handling, a dead body in an Ebola disease or MVD outbreak area, the body of a person who died of Ebola disease or MVD or had an illness compatible with Ebola disease or MVD, or who died of unknown cause after any potential exposure to an ebolavirus or marburgvirus
  • Living in the same household as a person with symptomatic known or suspected Ebola disease or MVD

1 Body fluids include but are not limited to feces, saliva, sweat, urine, vomit, sputum, breast milk, tears, and semen.

2 Recommended PPE should be sufficient to prevent skin or mucous membrane exposure to blood or body fluids.

Situations with Additional Exposure Potential

The following situations have potential for unrecognized ebolavirus or marburgvirus exposures and should be taken into account in the assessment of people who have been in an area affected by an Ebola disease or Marburg virus disease (MVD) outbreak in the previous 21 days but have no reported high-risk exposures.

Nonoccupational

  • Visiting a health care facility or traditional healer in an outbreak area
  • Attending a funeral or burial in an outbreak area

Occupational1

  • Providing health care or environmental cleaning in an Ebola disease or MVD treatment unit (E/MTU)
  • Entry into a patient care area of an E/MTU for any other reason
  • Providing health care in an outbreak area to acutely ill patients not known to have Ebola disease or MVD
  • Environmental cleaning in a non-E/MTU healthcare facility in an outbreak area
  • Clinical laboratory work associated with an E/MTU or other health care setting in an outbreak area
  • Burial work in an outbreak area

1These occupational exposure situations assume correct and consistent use of personal protective equipment (PPE). Correct and consistent use of PPE during situations with occupational exposure risk is highly protective and prevents transmission to healthcare or other personnel.  However, unrecognized errors during the use of PPE (e.g., self-contaminating when removing contaminated PPE) may create opportunities for transmission to personnel.

State, tribal, local and territorial authorities have primary jurisdiction for isolation and other public health orders within their borders. Federal public health authority primarily extends to international arrivals at ports of entry and to preventing interstate spread of communicable diseases.

CDC recognizes that decisions and criteria regarding when and how to use such public health measures may differ by jurisdiction. Consistent with principles of federalism, state, tribal, local, and territorial jurisdictions may choose to make decisions about the use of public health orders for isolation or quarantine, monitoring, and other precautions that provide a greater level of public health protection than is recommended in federal guidance.

Risk Assessment

An initial risk assessment for an ebolavirus or marburgvirus exposure should include whether the traveler:

  • was present (other than just transiting en route to airport) in a designated Ebola disease or MVD outbreak area
  • had any epidemiologic risk factors for exposure to an ebolavirus or marburgvirus or a person with Ebola or Marburg, e.g., as a caregiver, healthcare provider, laboratory worker, or burial worker
  • used personal protective equipment and other recommended infection control measures during any potential exposure
  • had any potential high-risk exposures

CDC has provided a list of situations with additional exposure potential to help guide traveler assessment, including decisions regarding testing for ebolaviruses or marburgviruses should a traveler develop compatible symptoms during the monitoring period.

A sample exposure screening and assessment tool is available here. [PDF – 2 pages]

Travelers should also be assessed for signs and symptoms of Ebola disease or MVD during the initial evaluation.

Health departments can consult CDC’s Viral Special Pathogens Branch (VSPB): call CDC’s Emergency Operations Center [770-488-7100] and ask to speak to VSPB’s on-call epidemiologist or email spather@cdc.gov) if they identify symptomatic or potentially exposed travelers, including travelers who were outside of designated outbreak areas. CDC requests notification regarding any travelers identified with potential high-risk exposures.

Health Education

Health departments should ensure all travelers from a country with a designated Ebola disease or MVD outbreak understand:

  • the signs and symptoms of Ebola disease or MVD and how to self-monitor
  • the need to self-isolate immediately if symptoms develop
  • how to notify public health officials should symptoms develop

CDC has posted After Travel recommendations for travelers from countries with Ebola disease or MVD outbreaks (also available in French, Spanish and Swahili). Health departments may choose to use this resource as part of their health education activities.

Monitoring and Other Public Health Interventions

Symptom monitoring for people with a potential ebolavirus or marburgvirus exposure can be conducted by phone, video conferencing, other electronic means (e.g., text message, email, app, web form), or in person, according to resources available in that jurisdiction, while the person is in the United States. The decision to monitor and frequency and method of monitoring should be guided by the results of the risk assessment, as specified below.

High-risk Exposures

Until 21 days after their last potential high-risk exposure, people with high-risk exposures should be:

  • Quarantined
  • Monitored daily
  • Restricted from traveling by commercial transport

CDC requests notification regarding any individuals identified with high-risk exposures. To make these notifications, health departments should call CDC’s Emergency Operations Center (770-488-7100) and ask to speak to the on-call epidemiologist for the Viral Special Pathogens Branch, or email spather@cdc.gov. See additional information in the section below.

Presence in a Designated Ebola disease or MVD Outbreak Area but no High-risk Exposures

In addition to an initial symptom screening during the risk assessment process, health departments should monitor travelers from a designated outbreak area who report having been in situations with additional exposure potential intermittently, at a minimum mid-way through and at the end of the 21-day period after the person left the outbreak area. For those who do not report having been in these situations, health departments may opt for self-monitoring, ideally with a single follow-up at the end of the 21-day period, to confirm the outcome of self-monitoring. All travelers from an outbreak area, regardless of health department oversight, should be advised to self-monitor and notify the health department if they develop symptoms during the 21-day period. CDC may additionally provide specific guidance for monitoring based on the assessed risk of case importation for an outbreak.

For guidance on healthcare providers’ return to work in the United States after caring for a patient with suspected or confirmed Ebola disease or MVD, visit Infection Prevention and Control Recommendations for Hospitalized Patients Under Investigation (PUIs) for Ebola Virus Disease (EVD) in U.S. Hospitals.

Presence in Country with Ebola disease or MVD Outbreak but not in Designated Outbreak Area

People who were present in an outbreak country but not in a designated outbreak area and who have no other epidemiologic risk factors should be advised to self-monitor and notify the health department if they develop symptoms during the 21 days after departing the outbreak country. CDC may provide additional guidance for these travelers based on the assessed risk of case importation for an outbreak.

Travel by People with No Known High-risk Exposures

People who have no high-risk exposures, and are asymptomatic, do not need movement restrictions and may travel. If they have been in a designated outbreak area and plan to travel to another U.S. jurisdiction during the monitoring period, they should notify the monitoring health department. The health department should notify the destination health department (for travel within the United States). The two health departments should agree as to whether responsibility for monitoring will be transferred, depending on the timing within the monitoring period and the duration of travel.

Table. Summary of Post-arrival Management Recommendations for Asymptomatic Travelers by Exposure Category

Table. Summary of Post-arrival Management Recommendations for Asymptomatic Travelers by Exposure Category
Intervention Reported high-risk exposure No reported high-risk exposures
Present in designated outbreak area and reports situations with additional exposure potential Present in designated outbreak area and reports NO situations with additional exposure potential Present in outbreak country but not designated outbreak area
Initial risk assessment Yes Yes Yes Yes
Health education Yes Yes Yes Yes
Symptom monitoring Daily Intermittent monitoring until 21 days after departure from outbreak area Self-monitoring, ideally with a single follow-up at the end of the 21-day period Self-monitoring
Movement restrictions Quarantine None None None
Travel Not permitted Advance notification to health department and coordination with destination health department Advance notification to health department and coordination with destination health department No recommendations

Symptomatic people with suspected or confirmed Ebola disease or MVD, and asymptomatic people with reported high-risk exposures

Health departments should conduct an assessment of any potentially exposed person with signs or symptoms compatible with Ebola disease or MVD to determine if the suspect case definition for Ebola disease or MVD is met and coordinate additional medical evaluation as needed. The purpose of the public health assessment is to ensure appropriate infection control precautions are in place during transport (see below) and at the healthcare facility for a patient who meets the definition of suspect case of Ebola disease or MVD. The assessment is also intended to minimize potential unintended consequences in managing a symptomatic traveler as a suspect case if the exposure risk is very low, including unnecessary implementation of infection control precautions suitable for Ebola disease or MVD or delayed recognition and management of other potentially life-threatening conditions while ruling out Ebola disease or MVD. CDC has published clinical guidance for assessing viral hemorrhagic fever risk in an international traveler and specific guidance for Ebola disease and MVD. The lists of high-risk exposures and situations with additional exposure potential provided in this guidance may also be useful in conducting these assessments.

If a diagnosis of Ebola disease or MVD is considered, state, tribal, local, or territorial public health officials should coordinate with CDC to ensure appropriate precautions are taken to help prevent potential spread of Ebola disease or MVD and to arrange for testing. As a resource for public health departments, CDC’s Viral Special Pathogens Branch (VSPB) is available 24/7 for consultations regarding suspected viral hemorrhagic fever or Ebola disease or MVD cases by calling the CDC Emergency Operations Center at 770-488-7100 and requesting VSPB’s on-call epidemiologist, or by emailing spather@cdc.gov.

Symptomatic people with suspected or confirmed Ebola disease or MVD should remain in isolation until they have been determined not to have Ebola disease or MVD (if suspected) or to be no longer infectious (if confirmed). Asymptomatic people with high-risk exposures to an ebolavirus or marburgvirus should remain in quarantine until 21 days after their last high-risk exposure. Quarantine or isolation may be voluntary or under public health orders, at the discretion of the health department of jurisdiction. Health departments may request use of federal public health travel restrictions for individuals with suspected or confirmed Ebola disease or MVD or with high-risk exposure, if they intend to travel before being cleared to do so by public health authorities, by contacting the CDC Port Health Station with jurisdiction for the area where the person is located.

People with suspected or confirmed ebolavirus or marburgvirus infection, and asymptomatic persons with high-risk exposures, are not permitted to travel by commercial transport until cleared by public health officials. If travel is necessary (e.g., to obtain medical care that is not available locally), transportation should be conducted in a manner that does not expose operators (e.g., air crews, bus drivers) or other travelers. The mode of transportation (e.g., ground vs. air transportation) should be determined by distance to final destination as well as the clinical condition of the traveler (i.e., whether medical care may be needed en route).

For international air transport of a person with suspected or confirmed ebolavirus or marburgvirus infection or high-risk exposure to a destination within the United States, per CDC regulations (42 Code of Federal Regulations, Part 71: Foreign Quarantine), the aircraft operator must notify CDC in advance through the CDC Port Health Station with jurisdiction for the port of entry or the CDC Emergency Operations Center (770-488-7100 or eocreport@cdc.gov). The aircraft operator should also coordinate with the U.S. embassy or consulate and health authorities for the country where the individual is located, CDC, the Federal Aviation Administration, and U.S. Customs and Border Protection, as well as appropriate foreign, state, tribal, local, and territorial governments to ensure compliance with all applicable laws and regulations; CDC can facilitate communications with U.S. jurisdictions as needed.