What is monkeypox? How contagious is it and what are the symptoms?

Toronto Public Health recently announced it is investigating the city’s first suspected case of monkeypox.

The Public Health Agency of Canada is also investigating about two dozen possible cases of the infection in the country, on top of two confirmed cases in Quebec

Monkeypox has historically been mostly contained to endemic areas in Africa but a recent rise infections in European countries, and now in North America, is leading to concern there could be community transmission.

What is monkeypox?

Monkeypox is a rare viral infection that is most common in rodent populations in Central or West Africa.

The virus can be transferred to humans from animals through bites or close contact and human-to-human transmission can then happen through prolonged contact or through bodily fluids. It was first identified in humans in 1970.

There have been several recorded cases in recent history of travellers carrying the infection from endemic areas in Africa to Europe or the United States.

Dr. Isaac Bogoch, infectious diseases specialist at the Toronto General Hospital, says the disease has typically been successfully contained in those instances.

“Once in a while there are cases that are isolated or identified in Europe,” he says. “Usually they’ve got a pretty strong travel history to West or Central Africa.”

A number of confirmed or suspected cases have been reported this month in several European countries. The World Health Organization have confirmed 80 cases of monkeypox and acknowledge the recent spread remains a mystery.

“Not many of these individuals are connected to travel to Africa where the disease is normally seen, so this is unusual. It’s unusual for the world to see this many cases reported in different countries outside of Africa,” said Dr. Theresa Tam, Canada’s Chief Medical Officer of Health.

How contagious is monkeypox?

Monkeypox is not believe to be as transmissible as other common viruses, including COVID-19.

The virus is thought to be transmitted through close physical contact, bodily fluids, or droplets. Though most health experts acknowledge there is not a lot of available data on the infection compared to other contagious viruses.

“It’s thought that people generally need to be in much closer proximity for a prolonged period of time for this to be transmitted,”Bogoch says.

The disease is also known to spread through contaminated clothing or bedding.

Monkeypox is not considered to be a sexually transmitted disease but close contact during sexual activity is considered a common form of transmission. Investigators in Europe say most of the cases there have been in gay or bisexual men, and officials are looking into the possibility that some infections were spread through contact during sex.

Previously, small outbreaks of the virus outside of Africa have been successfully contained.

“You can get these outbreaks under control,” says Bogoch, referencing a monkeypox outbreak in the U.S. in 2003 that was a result of different animals being housed together.

The outbreak started when a number of prairie dogs contracted the virus after sharing space with rodents from Africa. Some of the prairie dogs passed the virus on to humans and in the end around 40 or 50 individuals were infected before health officials were able to control the spread.

“Monkeypox outbreaks are not unprecedented, what’s different is this is transmitting from person to person without travel,” says infectious disease expert Dr. Amesh Adalja.

Related:

• Canada considering smallpox vaccine for monkeypox cases: Tam

What are monkeypox symptoms?

After exposure there is around a 10- to 15-day incubation period followed by flu-like symptoms and swelling of the lymph nodes.

Typically, infected individuals develop a fever or a headache followed by a rash with skin lesions. Bogoch says the type of lesions that come with monkeypox are not similar to lesions associated with chickenpox.

“With this type of infection, most of those lesions are at the same level of development,” he says. “They come on at a similar time and they evolve at a similar time.”

He says the infection is typically mild with rare instances of severe cases. The World Health Organizations says the disease can be fatal for up to 1 in 10 individuals, but severe cases are usually limited to younger age groups.

Most people recover from monkeypox within weeks with severe instances being much more common in children.

Is there treatment/prevention for monkeypox?

There are no treatments designed specifically for monkeypox.

While the typical monkeypox infection would likely not require any treatment, there are some drugs exist that would offer protection.

A vaccine that was originally developed for smallpox has been proven to be 85 per cent effective in preventing monkeypox.

“Many people over a certain age have received the smallpox vaccine and some people have a scar on their shoulder as proof of this,” says Bogoch. “That vaccine does provide some protection.”

Canada stopped routinely immunizing people against smallpox in 1972.

“I would say, generally, the entire population is susceptible to monkeypox,” Dr. Howard Njoo said Friday.

Public Services and Procurement Canada put out a tender last month to purchase 500,000 doses of the Imvamune smallpox vaccine on behalf of the Public Health Agency of Canada from 2023 to 2028.

There are other known treatments that were originally geared towards smallpox that also offer cross-protection. Smallpox was declared eradicated in 1980.

Is there cause for concern from the general public?

Most experts don’t think so.

Bogoch says there is no reason for panic in the general public but says it is important to be aware that there are chains of transmission that are not directly linked to travellers from endemic areas.

“I don’t think it’s time to be scared about anything, but it’s obviously time to take it seriously and at least acknowledge that this is here,” he says. “We’re going to hear about more cases popping up in different countries around the world.”

Despite the recent atypical spread of the disease, WHO still considers the risk to the general public to be “low” since the virus is not very contagious in regular social settings.

“There is a danger of viewing every further infectious disease outbreak through the lens of COVID-19,” says Adalja.

“You have to draw distinctions between a virus like SARS-CoV-2 and a monkeypox, which spread in a totally different way.”

With files from CityNews reporter Michelle Mackey, The Canadian Press and The Associated Press