Interim Guidance: Public Health Management of Cases and Contacts of Ebola Virus Disease in the Community Setting in Canada

June 22, 2015

The strategy outlined in this guidance is rapid case and contact management (i.e., to reduce opportunities for transmission to contacts and ensure timely assessment of contacts).  The objective of this guidance document is containment.

This guidance document updates the previous Public Health Management of Cases and Contacts of Human Illness Associated with Ebola Virus Disease (EVD) (Aug 23, 2014).  This updated guidance document:

This guidance document is based on currently available scientific evidence, expert opinion and guidance provided by other countries and agencies, e.g., World Health Organization (WHO), European Centre for Disease Prevention and Control (ECDC), United Kingdom (UK) and United States Centers for Disease Control and Prevention (CDC). This guidance document is subject to change as new information becomes available.  It should be read in conjunction with relevant federal, provincial and territorial (F/P/T) and local legislation, regulations and policies, and adapted to local context as required. This document has been developed based on the Canadian situation and therefore may differ from guidance developed by other countries.

Target audience and scope

The Public Health Measures Expert Task Group (PHM ETG) has developed this updated guidance with Public Health Agency of Canada (PHAC) Program Experts to support F/P/T and local public health authorities in the event that a case or contact of EVD is identified within their jurisdiction. The purpose of the PHM ETG, which consists of selected individuals who are recognized public health experts within Canada in the field of community based disease control strategies, is to provide a forum for expert public health measures discussions related to the prevention, control and mitigation of the spread of infectious diseases, including emerging infectious diseases, in the community.

Using a risk assessment approach, this guidance document provides advice regarding the management of symptomatic and asymptomatic contacts in the community. As with any guidance document, clinical judgement remains essential and this, along with jurisdictional policies, may result in decisions that differ from recommendations provided in this guidance document. Guidance pertaining to Laboratory/Specimen testing; Clinical Care; Infection Prevention and Control (IPC) measures in other settings (e.g., Canadian points of entry, healthcare settings, pre-hospital care settings, passenger conveyances, and airline cabins) are addressed in other guidance documents.

Beyond the scope of this document are requirements for:

Background

Although the risk of acquiring EVD in Canada is considered to be very low, it is conceivable that the introduction of a small number of cases connected to the outbreaks in EVD-affected African countries could occur.  It is anticipated that public health authorities at all levels (F/P/T and local) would be involved in the management of cases and contacts of EVD.  Public health activities are intended to rapidly identify EVD cases, with subsequent immediate actions for the management of cases and contacts of EVD to prevent spread. 

National case definitions for EVD have been established.  Published data on EVD are relatively limited; however, as more cases occur, Canadian public health authorities are taking every opportunity to learn from these experiences and to adjust recommended practices in Canada as required.

PHAC is working closely with its national and international partners to track and monitor EVD activity around the world and is assessing the risks of EVD in Canada on an ongoing basis.  Up-to-date case counts and further information on the ongoing outbreaks in West Africa can be found on the World Health Organization (WHO) website.

Epidemiology of EVD

EVD is a severe acute viral illness characterized by sudden onset of fever, fatigue, body aches, and severe headache, followed by sore throat, vomiting, diarrhea and, in some cases, maculopapular rash.Footnote2  Hemorrhagic symptoms may also occur in the later stages of disease.Footnote3 There is no licensed prophylaxis, treatment or vaccine available for protection against EVD; cases require hospitalization for supportive care and strict IPC management.

Incubation

The incubation period of EVD ranges from 2 to 21 days; there is no risk of transmission during the incubation period when the person has no symptoms.Footnote4 Footnote5

Mode of transmission

EVD is transmitted by direct contact (through broken skin or mucous membranes) i.e., touching the blood and/or other body fluids (e.g., feces, urine, emesis, saliva, sweat, breast milk and semen) of an infected individual, dead body or animal; and indirect contact through touching surfaces and fomites (e.g., needles) that are contaminated with blood and/or body fluids from an infected person or animalFootnote2.  EVD is not spread from human to human through airborne transmission or through casual interactions. Examples of casual interactions include sharing a seating area on public transportation or sitting in the same waiting room but no direct or indirect contactFootnote6.

Individuals infected with EVD are not considered to be communicable before the onset of symptoms, but communicability increases with increasing viral load which corresponds to worsening illness and the case remains communicable as long as blood and body fluids contain the virusFootnote5.  This timeframe includes the post-mortem period; the dead body of someone who died of EVD is highly infectious. Guidance regarding handling bodies of deceased EVD patients is available from Infection Prevention and Control Expert Working Group: Advice on Infection Prevention and Control Measures for Ebola Virus Disease in Healthcare Settings.

Convalescence

Surviving cases have fever for several days and typically improve around day 6-11Footnote7. Convalescence however is extended and often associated with sequelae such as myelitis, recurrent hepatitis, psychosis, or uveitisFootnote5.  During convalescence, Ebola virus may persist for weeks to months in some body fluids (e.g., semen, urine, and breast milk)Footnote8 Footnote9 Footnote10 Footnote11.  Sexual transmission of EVD can occur during the acute and possibly the convalescent periodsFootnote12.

Public Health Management of Cases, Persons Under Investigation and Convalescent Individuals

The role of public health in EVD detection and management is multifaceted and includes the early identification of cases and contacts through surveillance, conducting contact tracing, providing public and health care professional education and participating in communication activities.

Confirmed Cases

It is understood that confirmed cases of EVD will be hospitalized to provide appropriate management of the illness and to ensure effective isolation. It is recommended that public health liaise daily with hospital staff for the duration of the patient's hospitalization to monitor progress and be actively involved with discharge planning.

Persons under Investigation

The national case definition for a Person Under Investigation (PUI) is available.

In evaluating a person with possible EVD symptoms, healthcare providers and public health professionals should evaluate the person's epidemiologic risk, including a history of travel to a country with widespread EVD transmission or contact with a person with symptoms of EVD within 21 days prior to onset of symptoms.

Convalescent Cases

Convalescence following EVD is extended and often associated with sequelae such as myelitis, recurrent hepatitis, psychosis, or uveitis.  During convalescence, Ebola virus may persist for weeks to months in some body fluids (e.g., semen, urine, and breast milk).  Sexual transmission of EVD can occur during the acute and possibly the convalescent periods.Footnote12

Liaison between local public health authorities and hospital discharge planning staff regarding discharge planning is essential. Upon discharge of an EVD case from hospital, it is important that the case receives education and counselling as required for the associated sequelae resulting from the disease AND to prevent potential transmission to others during the convalescent period.

Key counselling points

  • Provide instructions regarding any medical follow-up that may be required;
  • Provide information regarding possible sexual transmission of EVD and:
    • Recommend that the individual either abstain from sexual contact or observe safe sex practices through correct and consistent condom use until the semen has twice tested negative.
    • Recommend semen testing at 3 months after onset of disease and then, for those who test positive, every month thereafter until semen tests negative twice, with an interval of one week between tests. Please refer to PHAC guidance on Ebola Specimen Testing for relevant specimen testing information.
    • If semen testing is not done, recommend that abstention or safe sex practices be continued for at least 6 months after onset of symptoms. This interval may be adjusted as additional information becomes available on the prevalence of Ebola virus in the semen of survivors over time. Additional information is available regarding sexual transmission of the Ebola Virus Disease.
  • Recommend that breastfeeding be discontinued until breast milk is confirmed negative for Ebola virus.

Public Health Management of Contacts

A contact is a person who has been or may have been exposed to a case (confirmed case or person under investigation), a case's body fluids or an Ebola virus contaminated environment.

The purpose of contact tracing is to:

  • Identify any symptomatic contacts as early as possible
  • Facilitate prompt laboratory diagnostic testing and treatment; and
  • Reduce the risk of transmission to others.

Contact Tracing

Should a confirmed EVD case be identified in Canada, local PH authorities would begin contact tracing.  Should a Person under Investigation (PUI) be identified, it is anticipated that PH authorities would consider the epidemiological and clinical suspicion that the PUI has EVD to assess the need to commence contact tracing.

For contact tracing purposes, the following factors would be taken into consideration:

  • Communicable period and communicability
    • only symptomatic individuals can transmit the infection;
    • infectiousness starts from the time of symptom onset;
    • evidence shows that in the early phase of EVD symptoms, the risk of transmission is low;Footnote13
    • individuals become more infectious with later stage symptoms such as diarrhea, vomiting or bleeding indicating a greater viral load;
  • Nature of the contact: transmission may only occur through direct contact with a confirmed EVD case or with their blood/body fluids, including deceased persons, or indirect contact with objects contaminated by blood or body fluids.
  • Incubation period (two to 21 days) to determine the length of time contact follow-up is required.

Risk Assessment of Contacts

All contacts of a confirmed case should be assessed by public health for their risk of exposure and to determine the appropriate public health recommendations. To facilitate the public health recommendations, contacts are classified as having low-risk exposure or high-risk exposure.

Contact with high-risk exposure includes any of the following:

  • Living in the same household and having direct contact with a confirmed case with EVD symptoms, such as bathing the individual, assisting with toileting, etc.
  • Direct contact with a confirmed case with EVD symptoms, their  body fluids, their dead body, or any other known source of Ebola virus without adhering to recommended IPC precautions;
  • Sexual contact with an acute or convalescent EVD case (see section Convalescent Cases - key counseling points, above).

Contact with low-risk exposure includes any of the following:

  • Living in the same household but did not have direct contact with the case; or
  • Having only casual interactions and no direct contact with an EVD case or their body fluids.  Examples of casual interactions include sharing a seating area on public transportation or sitting in the same waiting room.

Contact Management

The goal of contact management is to monitor an individual at risk of developing EVD symptoms and to minimize the risk of transmission to others. The public health guidelines for contact management in the Canadian community setting are detailed below and a supporting algorithm is located in Algorithm: Public Health Management of Cases and Contacts of Ebola Virus Disease in the Community.

It is acknowledged that public health authorities may need to enhance or tailor the recommendations to best manage various situations such as a situation of non-compliance and potential risk to public; in addition, in rare circumstances, the public health authority may choose to implement full quarantine measures or to issue an order under relevant provincial/territorial public health legislation to compel a person to comply with instructions.

Recommendations for all EVD contacts without symptoms, with low or high risk exposures

During the 21 day period following the last potential contact with EVD, it is recommended that all EVD contacts, regardless of their risk exposure:

  • receive active public health monitoring for symptoms check and counselling,
  • self-monitor for symptoms of EVD; including checking and documenting oral temperature twice daily and report to public health authority as directed (Temperature Recording Form for Contacts of Ebola Virus),
  • be prepared to immediately self-isolateFootnote14 and contact relevant public health authority should  EVD-compatible symptoms develop,
  • advise all healthcare providers that they encounter, including paramedic services, of their potential EVD exposure
  • try to avoid medications that are known to lower fever (e.g., acetaminophen, ibuprofen, acetylsalicylic acid) as these medications  could mask an early symptom of EVD; if these must be taken, advise your public health authority,
  • postpone elective medical visits and other elective procedures (e.g., elective dental visits, elective blood tests),
  • not donate blood or any other body fluid or tissue,
  • maintain good respiratory and hand hygiene practices, and
  • report any travel intentions outside of the public health jurisdiction to the public health authority.

Additional recommendations for contacts without symptoms who have had high-risk exposure

In addition to the recommendations for all EVD contacts, it is recommended that contacts who have had high-risk exposure:

  • remain near an acute care facility (e.g., within one hour's drive, if possible, in order to facilitate rapid transfer to the facility) where medical care with  appropriate IPC measures can be implemented.  Consider an EVD designated facility if possible.
  • avoid attending public places (e.g.,  grocery store, shopping mall, medical clinic, school, funeral, religious congregation).
  • avoid travel on public/commercial conveyances (e.g. bus, train, taxi, airplane).
  • further limit contact with others (e.g., quarantine) if appropriate based on the individual's risk assessment.
  • Limit or avoid contact with pets.

Recommendations for contacts who have developed EVD compatible symptoms

If a contact develops EVD compatible symptoms, public health authorities would:

  • arrange, as per P/T protocols, for the individual to have a medical assessment at an acute care facility (an EVD-designated facility, if located in close proximity to the individual) to confirm or rule out EVD. It is recommended that the individual not take public conveyances (bus, train, taxi) to that facility.  Depending on the nature/severity of symptoms and proximity to the facility, the individual may be able to take a private vehicle to the hospital and avoid direct contact with others or may need to take an ambulance to the hospital.Footnote15 It is important to ensure the Paramedic Services (if involved) and the receiving acute care facility are informed of the EVD-compatible symptoms in advance to help ensure that appropriate IPC measures are in place during transport and before their arrival at the acute care facility.
  • advise the individual to:
    • immediately self-isolate (maintain a 2 metre distance and no physical contact) if not already isolated from others,
    • wash hands, especially after vomiting or toileting,
    • ensure that others do not come into contact with their blood or body fluids (including urine, feces, emesis, saliva, sweat, and semen) or anything that may have come in contact with their blood or body fluid (e.g. linens, clothing, toilet, toiletries).  Refer to Measures for the Management of Ebola Virus Disease-associated Waste in Home or Alternate Settings for management of EVD associated waste.
      • urine, stool and emesis may be disposed of through the normal sanitary sewer system, or in accordance with municipal/regional regulations.Footnote16 Footnote17

Public health recommendations for specific groups and community settings

Community-based EVD-control strategies should be considered in the context of the current epidemiology of the disease and the evidence on effective public health measures.  The likelihood of EVD transmission from person to person in the community is dependent on the nature and timing of the exposure (directly from the infected individual or their body fluids while they are symptomatic).

Given the abundance of precaution being exercised for all potential contacts of EVD as described earlier, the risk to others through casual interactions is considered to be very low and therefore it is considered unlikely that EVD transmission will occur in a public setting such as in schools, at a shopping mall, grocery store, funeral or religious congregation in Canada.  Public health authorities should continually assess the potential risk for EVD transmission within the community and communicate relevant disease prevention advice as necessary.

Algorithm: Public Health Management of Cases and Contacts of Ebola Virus Disease in the Community Setting in Canada

Description of Algorithm

This algorithm describes the process for the Public Health Management of Cases of Ebola Virus Disease (EVD) in the Community Setting in Canada. It begins when a case of Ebola Virus Disease is identified in Canada with the subsequent identification of the case's contacts.

The advice contained in this algorithm should be read in conjunction with its parent document Interim Guidance: Public Health Management of Cases and Contacts of Ebola Virus Disease in the Community Setting in Canada and relevant federal, provincial, territorial and local legislation, regulations, and policies. Recommended measures should not be regarded as rigid standards, but principles and recommendations to inform the development of guidance.

Stage 1

This is a decisive point. Once the contacts have been identified, the following question should be asked: Does the contact have symptoms compatible with Ebola Virus Disease?

Stage 2

If the answer to the question in stage 1 is YES, the decision making pathway continues through stage 5 and these recommendations apply:

  • The person is contacted immediately to self-isolate and maintain a 2 metre distance from other people.
  • Advise that others in the household should not touch linens or waste that may be contaminated with the individual with possible Ebola Virus Disease's blood and or body fluids, until Ebola Virus Disease is ruled out.
  • Ensure appropriate transport to relevant health care facility (no public conveyances).
  • Ensure the Paramedic Services (if involved) and receiving acute care facility are informed of the Ebola Virus Disease-compatible symptoms in advance.
  • Ensure appropriate public health partners are identified.

Stage 3

This is a decisive point. An Ebola Virus Disease diagnostic test is conducted.

Stage 4

If Ebola Virus Disease is confirmed, commence a contact tracing cycle for this case.

Stage 5

If the Ebola Virus Disease diagnostic test is negative, continue to monitor until the end of the 21 day monitoring period.

Stage 6

This is a decisive point. If the answer to the question in stage 1 is NO, conduct an exposure and clinical risk assessment to determine if contact has had low risk exposure or high risk exposure.

Stage 7

Factors to determine if there has been a low risk of exposure include:

  • Living in the same household but did not have direct contact with the case or,
  • Having only casual interactions and no direct contact with an Ebola Virus Disease case or their body fluids. Examples of casual interactions include sharing a seating area on public transportation or sitting in the same waiting room but no direct or indirect contact.

Stage 8

Factors to determine if there has been a high risk of exposure include:

  • Living in the same household and having direct contact with a symptomatic Ebola Virus Disease case, such as bathing the individual, cleaning vomit, assisting with toileting.
  • Having direct contact with a confirmed case with Ebola Virus Disease symptoms, their body fluids, their dead body, or any other known source of Ebola virus (for example, their laboratory specimens) without adhering to recommended Infection Prevention and Control precautions, including selection and use of appropriate personal protective equipment.
  • Having sexual contact with an acute or convalescent Ebola Virus Disease case.

Stage 9

This is a decisive point. Once the risk exposure level has been determined, Ebola Virus Disease contact management should be implemented.

Stage 10

For ALL Ebola Virus Disease contacts (both low and high risk exposures); it is recommended that contacts:

  • Perform self-monitoring twice daily and receive active public health monitoring.
  • Self-isolate immediately if Ebola Virus Disease-compatible symptoms develop and advise public health authority and health care providers.
  • If possible, avoid medications that are known to lower fever and inform health authority if these must be taken.
  • Postpone elective medical visits and procedures.
  • Do not donate blood or any other body fluid or tissue.
  • Maintain good respiratory and hand hygiene practices.

Stage 11

Additional recommendations for contacts with HIGH risk exposures:

  • Remain near an acute care facility (for example, within one hour's drive, if possible, in order to facilitate rapid transfer to the facility) where medical care with appropriate Infection Prevention and Control measures can be implemented. Consider an Ebola Virus Disease designated facility if possible.
  • Avoid attending public places.
  • Avoid travel on public and or commercial conveyances.
  • Further limit contact with others, if appropriate as a result of individual risk assessment.

Stage 12

This is a decisive point. The question should be asked: Has the person developed Ebola Virus Disease compatible symptoms during the 21 day waiting period?

Stage 13

If the answer to stage 12 is NO, the recommendation is to discharge the patient.

Stage 14

If the answer to stage 12 is YES, The decision making pathway for stages 2, 3, 4 and 5 apply.

Tools and Templates

To support Public Health follow up of contacts, the following tools and templates can be found appended to this document:

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