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Screening for Respiratory Infectious Diseases (RIDs)

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This tip sheet helps employers and workers understand how screening can be used to reduce the transmission of respiratory infectious diseases in the workplace.

Pathogens (germs that cause disease) vary in their ability to spread and the severity of illness they cause. It is important to assess the risks associated with health hazards and implement multiple public health measures and workplace controls in a layered approach.

Screening is one of the controls that can help reduce the likelihood of a pathogen entering and spreading in the workplace.

Screening methods can help identify people who are:

  • Symptomatic: showing signs or experiencing symptoms of being infected with a respiratory infectious disease
  • Asymptomatic: not showing signs or experiencing symptoms but carrying the pathogen and can infect others
  • Pre-symptomatic: infected with the pathogen but not yet showing signs or symptoms. Some respiratory infections, like influenza and COVID-19, are contagious 24-48 hours before signs and symptoms appear

Screening can be placed into two major categories:

Screening is not required under normal working conditions in most workplaces. However, the local public health authority may advise that screening be done during a pandemic or similar serious public health occurrence, and compliance is recommended. If there is no legal requirement but an employer determines that screening would be an effective control for a respiratory infectious disease, they may follow guidance from the local public health authority or develop their own screening procedure.

Screening can be implemented in workplaces, even if not legally required, when there is increased risk of infection such as during a season of circulating respiratory infectious disease (e.g., flu season), or in settings where people at are greater risk of complications (e.g., long term care homes). A risk assessment can be a useful tool to help identify workplaces, tasks, and people at increased risk.

Note that diseases often have different signs and symptoms. Screening methods must be tailored to the respiratory infectious disease of concern.

Active Screening

Active screening occurs when information is gathered from individuals to determine if they might have a respiratory infectious disease. Note: this is not a clinical assessment or medical advice.

To be effective, all individuals (including visitors) should be screened before entering the workplace. Screening can also be useful before allowing work to be done at customer locations. Workers who live on-site (e.g., congregate housing, work camps, dorms) should be screened before starting their shift.

Several tools may be used to gather the required evidence:

  • Questionnaires: an individual answers screening questions in paper or electronic formats
  • Verbal screening: a designated person asks the individual a series of screening questions and may also record their answers on a questionnaire form
  • Observation: the screener observes individuals for obvious signs and symptoms of a disease. While in the working environment, workers should also be attentive for anyone displaying signs of illness
  • Temperature check: if a disease is known to cause fever, a contactless device designed to measure a person’s body temperature may be used in addition to screening questions
  • Testing: most respiratory infectious diseases can be identified with a test. This is the most reliable method of active screening but has limitations (e.g., cost, time to receive results, errors). A test is conducted on an individual’s sample (such as a nasal swab). Learn more about diseases and conditions to find out test options

Passive Screening

All individuals should self-monitor and self-report potential illness or exposure to a respiratory infectious disease. That is, if someone starts feeling sick or was exposed to a sick individual, they should inform their supervisor or employer. Passive screening should be continuous while in the workplace but is also important before entering the premises and beginning work.

Passive screening information can be communicated using:

  • Posters in locations where they can be easily seen, such as at entrances or notice boards
  • Workplace communication platforms (e.g., e-mails, company intranet, etc.)
  • Training

It should include:

  • The signs and symptoms of the respiratory infectious disease of concern
  • How and when to self-report

Screening Questions

Screening questions are used to identify potential illness or exposure situations. The questions must be appropriate for your jurisdiction, work setting, and the respiratory infectious disease of concern.

Consider these questions:

  • Have you recently tested positive for or been diagnosed with a respiratory infectious disease?
  • Are you experiencing any symptoms of a respiratory infectious disease like fever, coughing, or sore throat?
  • Have you been recently exposed to anyone who has tested positive for or has been diagnosed with a respiratory infectious disease?
  • Have you been recently instructed to isolate or quarantine by public health authorities?

Note that the above questions are non-specific. If there is a particular respiratory infectious disease that is the target of the screening, focus the questions on that disease (e.g., if screening for COVID-19, add questions about known COVID-19 symptoms, etc.).

Screening questionnaires may be used in verbal, paper, or electronic formats.

Symptoms of Respiratory Infectious Diseases

Symptoms vary between respiratory infectious diseases, and they only become noticeable after an incubation period (which may be days to weeks in duration). Many diseases share the same symptoms, making it difficult to confirm the cause of illness without a test or consultation with a healthcare provider.

Common signs and symptoms of respiratory infectious diseases include:

  • Fever
  • Cough
  • Sore throat
  • Nasal congestion

Diseases usually have more symptoms, some of which may be used to identify the pathogen. Learn more about the respiratory infectious diseases of concern to know the signs and symptoms to look out for.

How to Screen Workers, Customers, and Others

Any combination of screening tools suitable to your workplace may be used and tailored to the respiratory infectious diseases of concern (with the help of a risk assessment).

Customers, clients, and other visitors could be asked applicable screening questions when they are booking an appointment, and again at reception upon arrival at the premises. They could also be asked to read a checklist and confirm that they meet the criteria (such as not having any symptoms, etc.) to enter or be served.

When Someone Passes the Screening

If the individual passes the screening process, allow them to enter the premises or access your goods and services. Your jurisdiction may also require that you record everyone’s:

  • Name
  • Contact information (e.g., phone number or e-mail address)
  • Time spent on the site

All personal information must be safely stored and destroyed as required by privacy laws. Do not collect personal information if it is not necessary to do so.

When Someone Does Not Pass Screening

Anyone failing any part of the screening process should trigger a response appropriate to the situation and circumstances. Consider the following examples and possible responses:

  • An individual with a stable, chronic cough and no other symptoms of infection: allow entry
  • An individual with a cough that may be caused by a respiratory infectious disease seeking entry to a workplace with low risk of severe illness to others: allow entry and request that a suitable mask be worn (preferably a respirator or medical mask)
  • An individual with a cough that may be caused by a respiratory infectious disease seeking entry to a workplace with vulnerable individuals (e.g., medical facility with immunocompromised occupants): deny entry

Passive screening by individuals who are already in the workplace can result in a suspected positive case at any time. If this happens, the individual must be treated as if infected.

Follow your emergency response plan that is specific to the respiratory infectious disease of concern. The plan should follow guidance from the local public health authority while also meeting workplace-specific needs. A typical response to a respiratory infectious disease in the workplace can include the following steps:

  • Have the individual wear a mask (ideally a respirator or medical mask)
  • Request that they leave immediately and seek medical care

Call 911 for medical assistance if anyone experiences severe symptoms (e.g., difficulty breathing or loss of consciousness). Notify their emergency contact if the person is a worker.

Investigate all confirmed occupational diseases. Refer to guidance from your health and safety regulator and worker compensation board to determine legal reporting requirements.

For further information on respiratory infectious diseases, including COVID-19, refer to the Public Health Agency of Canada.

Disclaimer: As public and occupational health and safety information may continue to change, local public health authorities should be consulted for specific, regional guidance. This information is not intended to replace medical advice or legislated health and safety obligations. Although every effort is made to ensure the accuracy, currency, and completeness of the information, CCOHS does not guarantee, warrant, represent or undertake that the information provided is correct, accurate or current. CCOHS is not liable for any loss, claim, or demand arising directly or indirectly from any use or reliance upon the information.

Document last updated September 12, 2023