Mpox (formerly known as monkeypox) is a virus that can cause a rash, lesions or blisters. Before developing a rash, there is normally a period of fever, muscle aches and pains, and fatigue. Both animals and humans can contract the monkeypox virus, and it is spread by prolonged, close contact.
Prior to 2022, most cases of mpox were located in central and western Africa, and cases outside of these areas were very rare.
There have been 1,515 cases of mpox in Canada as of September 29th 2023.
The mpox outbreak in Canada peaked in 2022 and cases substantially dropped in 2023. However, in early 2024 there was a small increase in cases in Ontario.
As of February 26th, 2024, Ontario had seen 26 mpox cases this year compared to 23 cases in all of 2023. None of these new cases were in people who had been fully vaccinated (for more information on vaccines, see below).
For a more up-to-date count of reported mpox cases, we recommend you check out the Canadian government's official website.
Symptoms will often show after about 6-13 days of exposure but can take up to 21 days to appear.
These symptoms can include:
- Fever and chills
- Swollen lymph nodes
- Muscle aches and pains
- Headaches
- Exhaustion
- Rash or what appear to be blisters in your mouth, palms of the hands, soles of the feet, facial, genital area and/or in and around your butt
These symptoms can last from 2 to 4 weeks and will resolve on their own over time.
Mpox lesions can be flat or slightly raised and filled with clear or yellow fluid. They often will crust, dry up and fall off. Some people have very few lesions, while others may have thousands.
The mpox rash is typically located on the face, palms of the hands and soles of the feet. The recent outbreak of cases in Europe and North America has included cases with lesions limited to the mouth, eyes and/or genital area.
While severe cases can occur, this is very rare.
Fatality rates for mpox are usually estimated around 1-5%, but the strain detected in Europe and North America in 2022 is milder. In Canada there have been no deaths recorded as of September 29, 2023.
In the U.S. there have been 58 deaths out of 32,063 cases as of January 10, 2024. This represents a 0.18% fatality rate.
It is important to remember that anyone can contract the mpox virus, regardless of their gender, sexuality or sexual behaviour.
However, there are a number of factors that can increase risk:
- multiple sexual partners
- living in the same household as a person who has mpox
- providing care for a person who has mpox
- being immunocompromised
The mpox virus can be transmitted from person to person through contact with an infected person’s:
- lesions/sores
- blood
- body fluids (including respiratory droplets)
- mucosal surfaces (eyes, mouth, throat, rectal area)
- contaminated clothing or linens (bedding and towels)
The North American mpox outbreak has mostly affected the gbMSM community. This may be because gbMSM are a social network that have close contact with each other. Another possibility is that gbMSM are more proactive about their health and undergo STI testing on a more frequent basis.
The risk of mpox is not limited to gay, bisexual and men who have sex with men (gbMSM). Anyone in close contact with an infectious person is at risk regardless of their sexuality.
The World Health Organization has stated, “One reason we are currently hearing reports of cases of mpox from sexual health clinics in communities of men who have sex with men in this outbreak may be because of positive health seeking behaviour in this demographic.”
Mpox can resemble the rashes and lesions that are sometimes seen with other sexually transmitted diseases, which is a reason why these cases are being seen at sexual health clinics.
Several testing methods can be used for mpox, depending on the stage of the virus.
These tests can include:
- Blood tests
- Swabs of lesion fluid, scab or crusts
- Nasopharyngeal/throat swabs
If you have symptoms, it is suggested that you self-isolate and contact your healthcare provider. Your healthcare provider can guide you on testing and supportive care.
The smallpox vaccine called Imvamune is being used to vaccinate against mpox.
Imvamune is at least 85% effective in preventing mpox, and its safety has been evaluated in 20 completed clinical trials, where approximately 13,700 vaccines were administered to 7,414 people.
Imvamune is administered subcutaneously (into a fatty part of the body) and is divided into two doses given 28 days apart. Among the 2024 increase in cases in Ontario, none of these were in people who had received both vaccine doses.
The most common side effects seen with Imvamune include:
- discomfort at the injection site
- fatigue
- headache
- muscle pains
- nausea
The smallpox vaccine is safe to receive if you have received your COVID-19 vaccine.
Vaccine responses to mpox are managed by Public Health units.
Please note that there are certain criteria for receiving the vaccine and the Ministry of Health determines these.
The below resources can offer more information on upcoming vaccination sites.
Alberta
British Columbia
Manitoba
Ontario
Quebec
Saskatchewan
If you are outside of these areas, please check your local public health unit for more information about vaccination efforts.
Looking for additional resources to learn more about mpox? We recommend checking out the following resources to stay up to date.
