Infectious Agent

Mpox virus is a poxvirus (Family Poxviridae, genus Orthopoxvirus; other members include variola and vaccinia viruses)

Mode of Transmission


Close contact with an infected person or animal, or with material contaminated with the virus, such as bedding. Human-to-human transmission can occur through:

  • close contact with lesions on the skin, including during sexual contact
  • body fluids, including respiratory particles, containing infectious material
  • fomites, such as contaminated linen, clothing, or towels


  • Transmission via respiratory particles usually requires prolonged face-to-face contact, which puts health workers, household members and other close contacts of active cases at greater risk
  • Aerosol-generating procedures (AGP) are also a transmission risk
Incubation period

7-14 days with a range of 5-21 days. The rash usually evolves over 2-3 weeks

Infectious period

From the onset of the prodrome until the vesicles have scabbed over and the scabs have fallen off

Signs and SymptomsSigns and symptoms include:
  • prodromal period (initial symptoms) may include fever or chills, headache, myalgia, arthralgia, back pain, lyphandenopathy, fatigue.
  • later stage - A distinctive rash (lesions) usually begins within 1-3 days of onset of fever.  The rash typically begins in the oropharynx and then may appear on the:
    • face (95% of cases)
    • palms of the hands and soles of the feet (75% of cases)
    • inside of the mouth (70% of cases)
    • genitalia (30% of cases)
    • eyes (20% of cases)
The number of lesions vary from a few to several thousand and progress through four stages: macular, (lesions with a flat base) papular, (lesions slightly raised and firm), vesicular (filled with clear fluid) to pustular (filled with yellowish fluid), before scabbing over and resolving (usually takes 2-3 weeks). Unlike chickenpox where lesions in different stages can be present at a given time, all the lesions develop uniformly through the stages over 4-5 days. Lesions can be localised to a specific area of the body.


Atypical presentations have been observed e.g., patients with no or a mild prodrome, or a rash with few lesions or a single lesion only on genitalia or peri-anal region. Some cases present with proctitis (painful inflammation of the rectum) in the absence of rash or lesions. Hospitalisation is uncommon, and is usually for pain management, secondary skin infections, or other complications. More severe complications of Mpox can include cellulitis, pneumonia, sepsis, encephalitis and corneal infection.

* Although the virus is not considered to be a sexually transmitted infection, transmission can occur through intimate physical contact during sex. In this case, it is likely that infectious skin rashes, blisters or sores are the mode of transmission. In the current outbreak, men who have sex with men have been disproportionately impacted while noting that Mpox can effect anyone and as such vigilance is required with all patient cohorts

Precautions required

Contact and Droplet/Airborne:


  • Gloves
  • P2/N95 respirator (Fit tested and checked)
  • Eye protection
  • Gown/coveralls
  • Patient to wear a surgical mask if able to tolerate

Vehicle airflow

Ensure vehicle airflow set per WIAMB22 Ambulance Airflow (Login required)

Cleaning required

See Vehicle Cleaning and Spills Management - after transporting a patient requiring transmission-based precautions (contact, droplet/airborne)

Waste management

Heavily soiled items should be disposed of as clinical waste

Linen management

Items should not be shaken or handled in a manner that may disperse any infectious particles into the environment. All clothing and linen should be bagged at the location of use and placed within an impermeable bag. Seek guidance from the healthcare facility where the linen is being disposed

Shared transport

Patients who are symptomatic with suspected or confirmed Monkeypox must not share transport with other patients

Further resources

Clinical Resources Website

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