What is Monkeypox?

Monkeypox is a viral infectious disease caused by a family of viruses called orthopoxviruses. This family of viruses includes smallpox and cowpox. These viruses can be spread from animals to people and between people.  

People infected with monkeypox frequently develop a rash characterized by lesions. The lesions go through several stages before healing. At first, the lesions can look like pimples or blisters. They fill with fluid before drying up and falling off. The number of lesions varies from a few to several thousand.

Monkeypox lesions can be painful or itchy. They can appear on any part of the body.

The monkeypox rash frequently begins 1-3 days after the development of a fever. 

Other symptoms that may precede or follow the rash include:

  • headache (may be severe)
  • muscle aches
  • fatigue and exhaustion
  • swollen lymph nodes

Less common symptoms include:

  • cough
  • sore throat
  • vomiting
  •  diarrhea

Secondary complications from monkeypox infections include pneumonia, sepsis, encephalitis, keratitis, and/or vision loss.

Anyone can be infected with monkeypox. People who have had the smallpox vaccine are less likely to develop symptoms.

Monkeypox rash progression


Monkeypox is primarily transmitted through person-to-person contact, including skin-to-skin contact and contact with bodily fluids. It can also be transmitted through touching contaminated surfaces, like clothing, towels, or bedding.

Monkeypox can also be spread through respiratory secretions. The extent of transmission from large droplets and fine particles remains unclear. Until further data is available, CUPE recommends treating monkeypox as if it can be spread through both large droplets and fine particles. Large droplets are expelled when an infected person coughs, sneezes, or talks near another person. Fine particles are created by medical procedures like intubations, open suctioning, or bronchoscopies. They can also be created when large droplets evaporate. Fine particles may remain suspended in the air for some time.

Transmission window

Monkeypox symptoms typically start within 3 weeks of exposure, but can appear as early as 5 days after exposure.

The virus can be spread starting five days before the symptoms appear until the rash has completely healed.

Monkeypox usually lasts 2-4 weeks.


Employers should implement an exposure control plan (including up to date risk assessments). This should be done with the input of CUPE members like the Joint Health and Safety Committee.

The goal of an exposure control plan must be to eliminate exposure to the infectious virus as much as possible.

The methods of control against monkeypox infection should be the same as for other occupational hazards, and should follow the hierarchy of controls:

  • Engineering controls
  • Administrative controls
  • Personal protective equipment (PPE)

Monkeypox exposure control plan – elements to consider

Engineering controls (changes to physical equipment and processes)

  • Proper screening and management of suspected case
  • Using isolation and negative pressure rooms
  • Ensuring proper ventilation with appropriate level filtration units
  • Using source control masking
  • Adopting droplet transmission precautions
  • Adopting contact transmission precautions especially for handling linens, bedding, towels, clothing, etc.
  • Practicing physical distancing when possible

Administrative controls (changes to work practices)

  • Practicing regular and thorough hand hygiene
  • Stocking and managing the distribution of personal protective equipment (PPE)
  • Maintaining staffing that accommodates high rates of sick leave
  • Educating workers and the public
  • Adopting cleaning and laundering procedures to reduce the spread (including cleaning of high traffic areas, use of hospital grade laundry detergent, water temperature at a minimum of 70 degrees Celsius, disinfectants for equipment)
  • Ensuring infected or exposed persons are assessed by a healthcare professional and monitored for symptoms for 21 days
  • In the case of infection, self-isolating for up to one month or as determined by regional health authorities
  • In the case of infection, covering lesions with bandages when in contact with others.

Personal protective equipment (PPE)

Workers must have the proper PPE. This should include:

  • Fit-tested N95 respirators or more protective NIOSH-certified respirators
  • Gloves, face shields, and gowns
  • Annual fit-testing (or more often as required) droplet transmission precautions
  • Training and testing of workers on how to put on and take off equipment safely.

Monkeypox vaccine

The Imvamune® vaccine is authorized by Health Canada for immunization against monkeypox and orthopoxvirus infections in adults 18 years of age and older who are at high risk of exposure.

The National Advisory Committee on Immunization (NACI) recommends the Imvamune® vaccine be offered to people with high-risk exposures to a probable or confirmed case of monkeypox, or within a setting where transmission is happening.

The vaccine has been shown to significantly reduce symptomatic illness if received within 4 days of exposure to a person infected with the virus. It can be provided up to 14 days following exposure, which may lessen symptoms.

At the time of publication, most provinces experiencing monkeypox outbreaks are offering targeted vaccination campaigns. To find out if you are eligible, contact your local public health provider by calling 811 or by visiting your provincial health authority’s monkeypox information page (tip: Search with keywords “monkeypox vaccine” and the name of your province).

Additional information about monkeypox

Public Health Agency of Canada (PHAC) monkeypox outbreak home page:

PHAC Travel Health Notice:

CDC Information page on monkeypox: