Information on the viral zoonotic disease mpox for clinicians including signs and symptoms, primary and sexual health care, and on further guidance.
Last updated: 22 December 2022
On this page:
- Current situation
- Mpox signs and symptoms
- Primary health and sexual health care
- Further guidance and information
Current situation
Mpox is a zoonotic viral disease that can be transmitted by close contact with skin lesions, body fluids,and contaminated materials.
Mpox can also be passed on through breathing in droplets that have been exhaled by someone who has the virus. As this requires prolonged contact and for people to be very close together, the risk of the virus spreading in this way is very low. It is uncertain whether mpox is also spread through other bodily fluids (eg, semen).
A global mpox outbreak commenced in May 2022. Cases have now been reported in more than 100 countries. See mpox outbreak 2022 on the World Health Organization website.
The disease has spread to New Zealand, with the first case identified in July 2022. Cases have acquired the infection both overseas and in New Zealand.
See About mpox for more information.
Mpox signs and symptoms
Most people with mpox will develop a rash, spots or blisters on the infection site. These may spread to other parts of the body such as the palms of the hand, soles of the feet, inside the mouth, or on the genitals.
Other common symptoms can include:
- cold and flu symptoms such as a fever, chills or swollen glands
- headache
- muscle and body aches
- backache
- tiredness.
The rash associated with mpox may be generalised or localised and typically progresses through four stages:
- macular – flat, discoloured lesions
- papular – solid, raised lesions
- vesicular – fluid-filled lesions
- pustular – pus-filled lesions.
Once the rash associated with mpox has progressed through these stages, the lesions typically turn to scabs that will crust, dry or fall off.
Mpox symptoms usually resolve by themselves within two to four weeks.
Primary health and sexual health care
Clinicians are asked to look out for signs and symptoms consistent with mpox.
This is particularly important when seeing patients from groups disproportionately impacted by the current global mpox outbreak, which includes:
- men who have sex with men (MSM)
- people who have sex with MSM including transgender, cisgender and non-binary people
- anyone with two or more sexual partners or any anonymous sexual partners.
Information about all recent travel, sexual history and smallpox immunisation history should be collected where mpox is suspected.
Ensure that appropriate infection prevention controls such as a well-fitting mask and good hand hygiene are in place ahead of the consultation.
If mpox is suspected
When testing for MPX, clinicians should assess the case against the risk assessment criteria available in the Communicable Diseases Manual and on HealthPathways. Based on this assessment, inform the case whether they are required to isolate while their test result is awaited. All cases under investigation should be advised to avoid close contact (including kissing or sexual contact).
Confirmed cases are required to isolate for a minimum of seven days from onset of the first lesion or sign of skin rash. From day eight onwards, clinicians should then assess whether the case needs to isolate for longer, or if they can leave isolation with precautions in place to prevent spreading the virus to others.
Read more about people with mpox and isolation guidance.
Patients at higher risk of severe disease
While most people fully recover from mpox with supportive care only, some people are at an increased risk of potentially severe disease outcomes from mpox. We encourage healthcare providers who assess any suspected cases who meet any of the following criteria to have a further discussion with an infectious diseases or sexual health specialist about appropriate treatment options.
This includes people who are:
- Severely immunocompromised
- Children under 10 years of age
- Pregnant
- Older adults, particularly anyone over 60 years of age and Māori or Pacific peoples over 50 years of age
- Experiencing distressing symptoms or complications (eg, particularly uncomfortable lesions)
This is a guiding list based on the limited information currently available due to the relatively new nature of the mpox outbreak from the current viral variant. Healthcare providers are encouraged to seek further advice about anyone else for who they hold a clinical uncertainty, but does not otherwise fall into the above criteria of being at risk of severe disease.
Note: Medical care and therapy for the prevention and treatment of mpox is funded by Te Whatu Ora - Health NZ.
Further guidance and information
- Mpox infection prevention and control interim guidance for healthcare providers and health settings
- About mpox – includes guidance on testing, vaccination and preventing mpox transmission
- Advice for people with mpox and close contacts
- Communicable Disease Control Manual
- HealthPathways