As the number of mpox cases escalates in Africa and creeps upward in other countries like Canada, the World Health Organization (WHO), on Wednesday, again declared the virus a global public health emergency.

The declaration comes more than two years after the WHO first declared a global mpox emergency in 2022, which subsequently subsided in many regions. However, the virus has surged dramatically since January 2024, particularly in Africa, prompting health officials to describe the outbreak as “unprecedented.”

And here in Canada, Toronto Public Health is urging eligible residents to get vaccinated against mpox after a sharp rise in cases. On Tuesday, the local health unit said as of July 31 there have been a total of 93 confirmed cases of the virus compared with 21 cases for the same period in 2023.

As health officials grapple with the ongoing spread of the virus, complicated by the emergence of a deadlier strain in Africa, Dr. Mark Loeb, an infectious disease physician at McMaster University in Hamilton, Ont., expressed concern about its potential to continue spreading.

“There’s an explosion of cases in Central Africa, particularly in the (Democratic Republic of Congo), and there cases that are occurring in the surrounding countries, including Kenya, Rwanda and Uganda,” he told Global News.

“I think the countries that are under-resourced in terms of surveillance and in terms of management will have more deaths. And it’s affecting very young children. (There are) very high rates of mortality with this strain – it’s really important to get it under control.”

Originally identified in monkeys in 1958, mpox, previously known as monkeypox, was primarily confined to central and western Africa, and transmitted through close contact with infected animals.

However, a shift occurred in 2022 when the virus spread rapidly among people worldwide, including Europe, North America and beyond.

Mpox belongs to the same family of viruses as smallpox and causes similar, but generally milder symptoms.

“Mpox is a disease caused by a virus, and it causes symptoms such as a rash at the site of exposure. So if you’ve been kissing somebody, it may be on the face. If you’ve had sex, it might be in the genital area,” said Dr. Rita Shahin, an associate medical officer with health with Toronto Public Health.

“It’s often accompanied by other symptoms like fever, headache, muscle aches, feeling generally unwell. And most people recover within two to four weeks. But in a small number of cases, it can be more serious, leading to hospitalization.”

While not considered strictly a sexually transmitted infection, it is spread through contact with bodily fluids or scabs and contaminated personal items like clothing, bedding, sex toys or toothbrushes, according to Toronto Public Health.

Mpox is characterized by two distinct genetic variants known as clades I and II, which are endemic to central and west Africa, according to the WHO.

Clade I, known for being more transmissible and causing a higher rate of severe infections, stands in contrast to Clade II. The ongoing global mpox outbreak, which began in 2022 and continues to see cases reported worldwide, is caused by Clade II (including the mpox found in Canada).

In Canada, the vaccine Imvamune is an authorized shot used for immunization against smallpox and mpox in adults 18 years of age and older who are at high risk for exposure.

Vaccination involves two doses of the vaccine to provide the best protection, with the second dose being taken 28 days after the first one, according to the Public Health Agency of Canada (PHAC).

“We have a lot of people that were immunized in 2022 when we had our first outbreak. Those people are still protected, so they don’t need a booster dose. But anyone who hasn’t yet … should get the vaccine,” Shahin said.

“We really encourage people to get in touch with their sexual-health-care provider or book an appointment.

For individuals experiencing severe mpox symptoms, such as intense pain and fever, an antiviral drug called tecovirimat is available as a treatment option, Shahin said.

The Africa Centers for Disease Control and Prevention declared on Tuesday that the increasing spread of mpox across the continent is a health emergency, warning the virus might ultimately spill across international borders.

Africa has reported a staggering surge in mpox cases this year, with at least 14,000 infections and 524 deaths — a 160 per cent increase compared to the same period last year, according to the WHO.

The WHO said mpox was recently identified for the first time in four East African countries: Burundi, Kenya, Rwanda and Uganda. All of those outbreaks were linked to the epidemic in the Democratic Republic of Congo.

In the Ivory Coast and South Africa, health authorities have reported outbreaks of a different and less dangerous version of mpox that spread worldwide in 2022.

Earlier this year, scientists reported the emergence of a new form of mpox in a Congolese mining town that can kill up to 10 per cent of people and may spread more easily.

Unlike in previous mpox outbreaks, where lesions were mostly seen on the chest, hands and feet, the new form of mpox causes milder symptoms and lesions on the genitals. That makes it harder to spot, meaning people might also sicken others without knowing they’re infected.

Canada’s first significant mpox outbreak occurred in 2022-2023, peaking in late June 2022 with a total of 1,541 cases reported, according to PHAC data.

The outbreak disproportionately affected gay and bisexual men, and other men who have sex with men between the ages of 18 and 49 years. Most cases were reported in Ontario, Quebec and British Columbia.

While case numbers declined following the initial outbreak, a gradual increase in infections has been observed since early 2024 — mainly in Toronto, said Shahin.

“And more of a spike in June and July. It may be related to events such as Pride where people are meeting more partners, and (are) more social in the summertime. It’s hard to really say for sure exactly what’s behind it,” she said.

— with files from Global News’ Gabby Rodrigues and the Associated Press