Communicable Illnesses

Policy

A worker is entitled to benefits for a communicable illness arising out of and in the course of the worker’s employment. 

Purpose

The purpose of this policy is to provide entitlement guidelines for claims for communicable illnesses.

Guidelines

For the purposes of this policy, a "communicable illness" is defined as an illness resulting from infectious agents such as viruses, bacteria, and fungi. The transmission of these agents can be direct or indirect and varies based on the specific agent. Common transmission routes include person-to-person contact, animal-to-person interactions, ingesting contaminated food or water, contact with contaminated surfaces or objects, and exposure to infected soil or environmental sources. 

Entitlement criteria

In deciding whether a worker has initial entitlement to benefits for a communicable illness, a decision-maker determines whether: 

  • the worker contracted a communicable illness, and 
  • the worker's communicable illness arose out of and in the course of employment, in that the employment made a significant contribution to contracting the communicable illness.

Immunization status

Entitlement to benefits will not be denied solely because the worker is not immunized against the communicable illness for which there is a claim for benefits.

Standard of proof

The standard of proof that applies to all issues when making entitlement decisions in communicable illness claims is balance of probabilities. However, when the evidence for and against an issue related to a worker’s claim is evenly balanced, the worker must be given the benefit of the doubt, see 11-01-13, Benefit of Doubt. 

Gathering and assessing the evidence

Work-related communicable illnesses are caused by various infectious agents. Although not all communicable illnesses are widespread, illnesses like influenza, COVID-19, and norovirus can be prevalent in the community. Consequently, individuals may encounter multiple potential sources of infection, both within and outside of employment. 

When adjudicating communicable illness claims, decision-makers must gather and weigh all of the relevant evidence, including medical records and evidence from both employment and non-employment contexts, to evaluate potential sources of infection. In all cases, to allow the claim, the decision-maker must be satisfied that the evidence supports that the worker contracted a specific communicable illness and that it is or is most probably work-related. 

The central consideration is the strength of the evidence linking the communicable illness to employment. If this evidence is sufficiently strong, on balance, the identification of a specific contact source within the employment setting is not necessary to establish the illness as work-related. Conversely, if this evidence is lacking, or if there is more persuasive evidence supporting that the source of the illness is outside of employment, the illness may be found to be non-work-related.

Determining whether the worker contracted a communicable illness

The nature of the evidence required to establish that a worker contracted a communicable illness can vary based on the diagnostic criteria for the communicable illness and the unique circumstances of the case.

Generally, to establish that a worker contracted a specific communicable illness, one or both of the following will be necessary:

  • confirmatory testing of infection (i.e., a positive result from a laboratory or diagnostic test that establishes the presence of the infection), 
  • a diagnosis by a treating health professional qualified to provide such a diagnosis based on a clinical assessment of the worker during the period of illness.

In certain situations, other evidence may be sufficient to establish that a worker contracted a specific communicable illness, including:

  • a serology test to detect a past infection,
  • results of a Health Canada approved point-of-care test showing a current infection, provided it aligns with public health guidance, 
  • a report from a coroner, indicating the cause of death or a contributing factor to the death,
  • the worker’s signs and symptoms, where they align with a communicable illness known to be prevalent in the employment setting, especially considering the worker’s exposure history (e.g., norovirus).

Delay in seeking health care attention

Decision-makers use the “five-point check system” when determining initial entitlement. One of the five points is establishing proof of accident. In the context of a communicable illness claim, valid reasons for a delay in seeking healthcare attention that will not detract from establishing proof of accident, include, but are not limited to:

  • the worker cannot access or does not qualify for laboratory or diagnostic testing, 
  • the worker was following the guidance or direction of a public health authority (e.g., quarantine or self-isolation).

For more information on proof of accident, see 11-01-01, Adjudicative Process.

Determining whether the communicable illness arose out of and in the course of employment

A communicable illness is considered to arise out of and in the course of employment when, after evaluating all the relevant evidence, including any evidence suggesting the illness was contracted outside of employment, the decision-maker is satisfied that the worker's employment significantly contributed to contracting the illness through the performance of a work-related duty or an activity reasonably incidental to employment. For more information on the application of the criteria of place, time, and activity, see 15-02-02, Accident in the Course of Employment.

In determining if a worker’s employment significantly contributed to contracting a communicable illness through the performance of a work-related activity, one of the following must generally be met: 

  1. Established work-related source:
    There is clear and convincing evidence that the communicable illness was contracted from an established work-related source of the illness during the performance of a work-related activity, in a manner consistent with the recognized mode of transmission for the illness. For example, a laboratory worker gets splashed to the eyes with blood known to be infected with hepatitis B while transporting it. 
  2. Increased risk due to employment: 
    The worker’s employment placed the worker at an increased risk (i.e., increased likelihood) of contracting the communicable illness compared to the risk experienced by the general public during typical daily activities. As elaborated in the following subsections, the evidence must support that it is probable, rather than merely possible, that the worker’s employment significantly contributed to their contracting of the communicable illness. For example, a childcare worker contracts norovirus after multiple cases among children on the floor of their childcare facility. The childcare worker is at an increased risk compared to the public, who would not be exposed to multiple norovirus cases during typical daily activities.

Increased risk factors
A worker's employment will generally place the worker at an increased risk of contracting a communicable illness compared to the risk experienced by the general public during typical daily activities when:

  • the rate of the communicable illness is higher in the employment setting than in the general population (e.g., widespread outbreak in the workplace, treatment or care of populations with a significantly higher rate of the illness, or travel to a region with a significantly higher rate of the illness), or
  • the worker's employment activities create opportunities for exposure to and transmission of the communicable illness in excess of the opportunities associated with typical daily activities, such as:
    • activities that require a worker to have contact with one or more person(s) known to have or suspected of having the communicable illness in the context of delivering health care, personal care, emergency aid, custody, or transport to these persons,
    • activities that require contact with animals known to be or suspected to be carriers of the communicable illness or, where applicable, with environments heavily contaminated with their excrement,
    • activities that require handling or contact with materials susceptible to fungal contamination (e.g., soils),
    • activities that require the worker to have contact with infectious substances, or with objects or surfaces contaminated with these substances, such as the body fluids of persons known to have or suspected of having the communicable illness, and
    • staying in employer-provided accommodations with one or more person(s) known to have or suspected of having the communicable illness (e.g., accommodations in remote mining camps, accommodations provided to temporary foreign agricultural workers). 

Relevant factors to consider in determining work-relatedness

Relevant factors that a decision-maker should consider when determining whether the infection occurred as a result of work-related activities include: 

  • Potential exposure to the communicable illness within as well as outside of the worker's employment: Comparing exposure risk in employment settings versus personal settings, including contact with known sources of the communicable illness, can help identify high-risk exposures and, therefore, assess the most likely source of a worker's infection. 
  • Mode of transmission of the communicable illness: Understanding the mode of transmission (e.g., contact, droplet, airborne, oral) in relation to the employment setting helps assess the likelihood of the employment as the source of the worker’s infection. For instance, riskier environments for airborne diseases are enclosed spaces without adequate ventilation.
  • Duration, frequency, and intensity of potential exposures: The quality and quantity of different exposures can have varying risks. For instance, direct and prolonged exposures may heighten the risk of infection. The frequency of exposures can also be a strong indicator of the likelihood of infection. 
  • Control measures implemented in the workplace: Control measures implemented in the workplace, including the use of personal protective equipment to protect workers from exposure to communicable illnesses, may lower the risk of infection. The extent to which control measures lower risk depends on the totality of the circumstances. This includes the specific control measure(s) in place, the employment environment, the mode of transmission and other characteristics of the communicable illness, and the duration, frequency, and intensity of potential exposures. 
  • Compatibility with incubation period: If the time elapsed between symptom onset and a probable transmission event falls within the incubation period, it strengthens support for a specific event being the source of the infection. Alternatively, if the time elapsed between symptom onset and the probable transmission event falls outside the incubation period for the communicable illness, the transmission event is less likely to be the source of the infection.

Community-acquired communicable illnesses

Communicable illnesses, like influenza and COVID-19, are easily transmitted and often widespread in the general population. In-person interactions that can easily spread these communicable illnesses are a part of everyday life and occur both within and outside of employment, including in the home, community, and public settings. Outside of a public health emergency, evidence that a worker has frequent in-person interactions at work (e.g., with colleagues, customers, and clients) is too speculative, on its own, to support a conclusion that the worker’s employment significantly contributed to their contracting of the communicable illness. For initial entitlement to benefits, there must be evidence which makes it probable, rather than merely possible, that the worker’s employment significantly contributed to their contracting of the communicable illness.

Public health emergency

During a government-declared public health emergency related to a communicable illness, a worker’s employment-related risk of contracting that communicable illness may be increased when:

  • the public health emergency results in the implementation of public health measures to control or prevent the spread of the communicable illness in the general public (e.g., stay-at-home orders), and
  • the worker is employed as an essential worker at a workplace that continues operations during the public health measures and has in-person interactions as part of their job duties. 

Loss of earnings (LOE) benefits and period of communicability

In this section, "period of communicability" means the time during which an infectious agent may be transferred directly or indirectly from an infected person to another person. During this period, a worker with a communicable illness poses a risk of transmitting it to others in the workplace. 

When a claim for a communicable illness has been allowed, a worker may be entitled to LOE benefits for the period of communicability, even if the worker is asymptomatic or only has mild symptoms, if the communicability of the worker prevents or limits their ability to return to work, see 18-03-02, Payment and Reviewing LOE Benefits (Prior to Final Review) and 19-02-08, RTW Co-operation Obligations.

No entitlement for prevention of communicable illnesses

A worker exposed to a communicable illness in the workplace but showing no symptoms and having no laboratory confirmation or clinical diagnosis of illness may be legally required to self-isolate or may be sent home by the employer. Workers who do not have a work-related communicable illness are not entitled to benefits under the Workplace Safety and Insurance Act, 1997 for the time they remain out of the workplace on a precautionary basis. However, if a worker subsequently develops symptoms or tests positive for the communicable illness, they may be entitled to benefits. 

NOTE

The WSIB may provide benefits for post-exposure prophylaxis (PEP) following an established work-related exposure to a communicable illness through accidents, such as needlesticks, bites, or cuts, provided there is a substantial risk of infection and an available PEP treatment. See 23-01-01, Post-exposure Prophylaxis for Occupational Exposure to HIV.

Application date

This policy applies to all claims for a communicable illness with an accident date on or after December 1, 2023.

Document history

This is a new document. 

Policy review 

This policy will be reviewed within two years of the application date.

References

Legislative authority 

Workplace Safety and Insurance Act, 1997, as amended
Sections 2, 13, 43, 159 

Minute

Administrative
#1, November 3, 2023, page 625