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Updated guidance for infection prevention and control in health care settings when COVID-19 is suspected or confirmed – April 2024

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Introduction

Preamble

This document updates the previous guidance document "Update with consideration of omicron: Interim COVID-19 infection prevention and control in the healthcare setting when COVID-19 is suspected or confirmed-December 23, 2021" with revised recommendations for:

Background

This document, which updates previous national Infection Prevention and Control (IPC) guidance developed for health care settings for IPC interventions to prevent and control COVID-19, was informed using expert advice from the National Advisory Committee on Infection Prevention and Control (NAC-IPC), by reviewing available scientific evidence and completion of an environmental scan of international, provincial and territorial guidance.

For the purposes of this document, the term "patient" includes persons receiving health care who are traditionally/routinely referred to as patients, clients or residents.

Risk and transmission

SARS-CoV-2 proved to be a rapidly mutating virus, with the development of multiple variants impacting transmissibility, and vaccine effectiveness. Factors affecting the risk of acquisition of healthcare-associated SARS-CoV-2 infections include:

Respiratory particles (respiratory droplets and small aerosol particlesFootnote a) continue to be the primary source of transmission for SARS-CoV-2. Infections can occur when respiratory mucosa (eyes, nose or mouth) are exposed to infectious respiratory particles. Individuals who are infected with SARS-CoV-2 virus can release infectious respiratory particles in a range of sizes when talking, breathing, singing, exercising, coughing, sneezing. These particles can remain suspended in the air and be inhaled into the respiratory tract of another person and cause infection. It is also assumed that some degree of contact transmission occurs through contaminated surfaces or objects.

Aim and scope

The Public Health Agency of Canada (PHAC) develops national evidence-informed IPC guidance to complement provincial and territorial public health efforts in monitoring, preventing, and controlling healthcare-associated infections. Guidance will evolve with new scientific evidence, as well as with careful consideration of implications for practice in areas of uncertainty. National-level guidance should always be used in conjunction with relevant provincial, territorial and local policies and regulations. PHAC guidance does not supersede provincial, territorial, and local policies and regulations. PHAC will continue to consider new evidence as it becomes available. This guidance is for all healthcare settings (acute care, long-term care, home care and ambulatory/outpatient care). For guidance on public health measures for COVID-19, please refer to Coronavirus disease (COVID-19) - Canada.ca

Hierarchy of controls

Continue to implement and re-evaluate the hierarchy of controls within the healthcare environment including:

Engineering controls

Administrative controls

Screening and surveillance

Patient placement and accommodation

A patient who is suspected or confirmed to have COVID-19 should be cared for in a single room, on precautions with a toilet and sink designated for their use. If no single rooms are available, cohorting patients with confirmed COVID-19 could be considered in consultation with IPC. All facilities should have a pre-established cohorting plan.

Clear signage (universal infographics/multilingual as required) indicating Droplet and Contact precautions with appropriate PPE (for COVID-19) should be in place, and posted in such a way that is clearly visible to all entering the patient room or bed space.
Posters illustrating the correct method for donning on and doffing PPE should be considered for display inside and outside of each room of a patient who is suspected or confirmed to have COVID-19 for easy visual cues.

Personal protective equipment

Recommended PPE for all patient encounters should be based on a Point of Care Risk Assessment (PCRA) which should include consideration of:

Recommended PPE for direct care of patients with suspected or confirmed COVID-19:

Every HCW should have access to a fit-tested respirator, so that they can put it on quickly if the need is identified during the PCRA.

Consider implementing universal use of respirators for all HCWs during all patient care encounters in specific units or areas of facility at higher risk of SARS-CoV-2 transmission, e.g., COVID-19 designated units, emergency departments, open space critical care areas, areas with high frequency of aerosol-generating medical procedures (AGMPs), etc.

Routine practices and additional precautions

Routine practices, including hand hygiene, are in place for the care of all patients. In addition to routine practices, droplet and contact precautions with appropriate PPE for COVID-19 should be used when caring for patients with suspected or confirmed COVID-19. Please refer to PHAC's Routine Practices and Additional Precautions for Preventing the Transmission of Infection in Healthcare Settings (2013) guidance document.

Information should be provided to staff, visitors, and patients who are asked to wear a respirator or medical mask about the importance of performing hand hygiene prior to putting on, and after removing or touching their mask, to reduce risk of self-contamination.

Individuals should also be informed about the steps for proper hand hygiene, and that wearing a respirator or medical mask does not lessen the need to adhere to other measures to reduce SARS-CoV-2 transmission.

Communication materials for visitors should consider the needs of diverse populations such as those with disabilities and those who may not be fluent in either English or French.

Aerosol exposure and aerosol-generating medical procedures (AGMPs)

Historically, certain medical procedures, known as AGMPs, were thought to pose a higher risk for HCWs on the basis of case–control studies, mainly from SARS-CoV-1, which reported associations between selected procedures and HCW infections. As evidence is evolving it remains prudent to continue to use fit-tested, seal-checked N95 respirators, eye protection, gowns and gloves for all AGMPs on patients with suspected or confirmed COVID-19.

Discontinuation of additional precautions

The duration and discontinuation of additional precautions for an individual patient or unit (where precautions may be universally applied during a COVID-19 outbreak) should be determined on a case-by-case basis, in consultation with the IPC program and in accordance with local, provincial or territorial public health guidance and organizational policies. The duration of additional precautions for a symptomatic patient with COVID-19 should be for a minimum of 10 days from onset of symptoms (and a minimum of 10 days from first positive testing for patients who remain asymptomatic), and may be longer dependent upon duration of symptoms, disease severity and the presence of any underlying immunocompromising conditions.

Masking for source control

Medical masks can be worn by HCWs, staff, patients, visitors, caregivers, and any other individual present in the healthcare setting for the purpose of protecting others by preventing the spread of bacteria and virus to others. This is known as masking for source control. This can be applied at the individual level (e.g., individual with respiratory signs or symptoms) or more broadly (e.g., all HCWs, visitors, and patients). Masks used for the purpose of source control should be of medical grade and well-fitting.

Individual masking for source control

Broader masking for source control

If implementing broad masking for source control, consider the impact on persons with cognitive impairment or where masks could impede communication or otherwise hinder the ability to provide equitable care.

Implementation of broad source masking may vary based on jurisdictional and facility-specific context, including organizational risk assessment.

Patients who are unable or unwilling to mask should not be denied care. Protocols should be in place to allow for the safe assessment and treatment of symptomatic, unmasked patients. Patient masking is not recommended for paediatric patients two years of age or younger or for any patient unable to tolerate masking for medical or developmental reasons.

Visitors

Visitation policies and restrictions may vary across jurisdictions and facilities depending on the degree of local transmission of SARS-CoV-2. Policies should aim to balance the risk of introduction and transmission of SARS-CoV-2, and the promotion of patient and family-centered care including physical, psychological, emotional and spiritual needs of patients.

Visitors exhibiting signs or symptoms of an acute respiratory infection, including COVID-19, should not enter the facility. However, if visitation is required (e.g., end of life decisions), refer to institutional policies and procedures.

IPC information including the importance of adherence to IPC measures should be provided to visitors.

Communication materials for patients and visitors should address the needs of diverse populations such as those with disabilities and those who may not be fluent in either English or French.

Footnotes

Footnote 1

There is a transition away from the use of the terms "droplet" and "aerosol" as evidence suggests that respiratory particles exist on a continuum of sizes. As these terms are still commonly used in practice, they are included for clarity and to ensure appropriate application of IPC precautions.

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