Expert explainer: Dr. Sameer Elsayed on monkeypox and what Canadians need to know

 Monkeypox cases are being reported in Quebec, Ontario, Alberta, and British Colombia.

Dr. Sameer Elsayed is an infectious diseases physician and professor in the Departments of Medicine, Pathology & Laboratory Medicine, and Epidemiology & Biostatistics at Western University. He is also a consultant for Infectious Diseases, Medical Microbiology, and Internal Medicine.

Elsayed explains the risks and concerns surrounding these outbreaks in Canada and what the public can do to protect themselves from infection.


What is monkeypox and how does it affect the human body?

Monkeypox belongs to a group of closely-related viruses that includes smallpox, cowpox, and camelpox. Monkeypox virus was first discovered in 1958 as the cause of a non-fatal smallpox-like skin disease of captive monkeys at a research facility in Denmark. Infections of monkeys at research institutions in the Netherlands and United States were noted a few years later. However, the virus is found in nature only in Central and West Africa. The name monkeypox is a misnomer since terrestrial African rodents (rats and squirrels) serve as the natural reservoir of the virus while monkeys and other primates are believed to have been accidentally infected.

What is the mortality rate for this disease and beyond mortality what are some other long-term effects?

The human mortality rate from monkeypox infection depends on a number of factors, including the underlying health status of an individual, mode of acquisition, exposure level, the specific strain of the virus, and smallpox vaccination status. There are two strains (variants) of monkeypox virus that have been described in Africa. The mortality rate for the West Africa strain is approximately 3.6 per cent while the mortality rate for the Central African strain is about 10.6 per cent. However, these rates were based on research conducted in Africa between the 1970s and 1990s and may not be commensurate with what would be expected for incidental infections seen among individuals living in developed countries.

Human monkeypox infection is not new to the Europe and North America. An outbreak of human monkeypox infection involving over 80 children and young adults in several Midwest U.S. states occurred in 2003 after these individuals acquired exotic pet dogs which became ill after contact with African rodents during importation. There were no human deaths, although three children experienced severe illness but eventually recovered. Between 2018 and 2021, several travel-associated cases of monkeypox infection were noted among visitors to Nigeria who returned to the United Kingdom, Israel, Singapore, and the U.S., with no deaths reported.

To date, there have been more than 550 confirmed cases of human monkeypox infection in the North America and Europe, with no deaths reported. All infections in this outbreak have been due to the West African variant, which appears to cause milder symptoms.

How transmissible is monkeypox and how can people protect themselves?

Human to human transmission of monkeypox virus occurs through close contact with skin lesions or their body fluids, contaminated respiratory particles (generated by coughing, sneezing, talking) or contact with oral secretions, or indirectly through shared bed linens, towels and kitchen utensils. Unlike COVID-19, there is no evidence that monkeypox virus is transmitted by the airborne route. Animal bites and consumption of animal meat are common ways of acquiring the infection in Africa although physical contact remains the most frequent mode of transmission. In humans without prior smallpox vaccination, the chance of a close household contact becoming infected is between seven and 12 per cent, compared to three per cent or less for non-household contacts.

For individuals with suspected or confirmed monkeypox infection, a surgical mask should be worn to prevent spread of respiratory droplets to others. Dressings should be used to cover all skin lesions until they have crusted over. Personal use items (e.g., towels, kitchen utensils) should not be shared. Disinfectants such as diluted bleach or ethyl alcohol can be used to decontaminate frequently touched surfaces.

Is there an effective vaccine for monkeypox?

The U.S., Canada and Europe maintain ample stockpiles of live vaccines that are effective against smallpox and monkeypox. These vaccines are not actually derived from smallpox or monkeypox viruses but rather from the closely related cowpox virus. Rare but serious side effects may be experienced following older generation smallpox vaccines. These side effects may include a generalized skin rash or a widespread skin infection from the vaccine. A newer generation live vaccine that is safe for use in almost all individuals, including those whose immune systems are compromised, is now available, although current stocks are limited. These newer vaccines are being recommended for laboratory workers who perform monkeypox testing, as well as for healthcare workers who administer smallpox vaccine or who care for patients with monkeypox.

For further information on monkeypox from Dr. Sameer Elsayed please follow this link:

Commentary reflects the perspective and scholarly interest of Western faculty members and is not an articulation of official university policy on issues being addressed.

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