Canada now has 77 confirmed cases of monkeypox, according to figures supplied Friday by Canada's chief public health officer and Santé Québec, the provincial health ministry.
Of the cases identified so far through laboratory testing, 71 are from Quebec, five are from Ontario and one is from Alberta.
The figure is more than 15 times higher than the five confirmed cases the Public Health Agency of Canada (PHAC) reported nationwide late last month.
While a disproportionate number of cases in this monkeypox outbreak have shown up among gay and bisexual men, Chief Public Health Officer Dr. Theresa Tam told reporters Friday that all groups are potentially susceptible to the virus.
"The risk of exposure is not exclusively related to any group or setting. No matter your gender or sexual orientation, anyone could get infected and spread the virus if they come into close contact — including intimate sexual contact — with an infected person or their contaminated objects," Tam said.
With that caveat, Tam said it's important that public health officials "learn from the HIV experience" and "involve communities right from the start that are most impacted."
She said governments must "act fast" to "stop the chains of transmission" and prevent the virus from spreading further.
"At the moment it hasn't gone beyond the initial risk groups, but it could happen and we need to be ready for that," she said.
The World Health Organization (WHO) issued public health advice to gay, bisexual and other men who have sex with men last week, urging the community to be on the lookout for certain symptoms — a rash leaving blisters on the face, hands, feet, eyes and mouth, fever, swollen lymph nodes, headaches, muscle aches and a lack of energy.
Quebec appears to be an epicentre of this outbreak. The province has started vaccinating the close contacts of infected people — a so-called "ring vaccination" approach to prevent a wider outbreak.
Tam said Canada has a stockpile of smallpox shots ready to deploy to other parts of the country, if necessary.
Smallpox and monkeypox belong to the same family of viruses and the smallpox vaccine has proven effective against monkeypox in the past. But that shot has not been in circulation in Canada for decades because smallpox was eradicated here in the late 1940s.
Monkeypox is a viral zoonotic disease that occurs primarily in tropical rainforest areas. Historically, most cases have been reported in the Congo Basin.
The emergence of this virus in Western countries has confounded researchers. To date, the WHO has identified at least 550 monkeypox cases in 30 countries worldwide where the virus is not believed to be endemic.
In a recent interview with The Associated Press, Dr. David Heymann, who once headed WHO's emergencies department, said the leading theory to explain the spread of the disease is sexual transmission among gay and bisexual men at two raves held in Spain and Belgium.
"We know monkeypox can spread when there is close contact with the lesions of someone who is infected, and it looks like sexual contact has now amplified that transmission," said Heymann.
Madrid's senior health official said last week that the Spanish capital has confirmed 30 cases so far.
Enrique Ruiz Escudero said authorities are investigating possible links between a recent Pride event in the Canary Islands, which drew some 80,000 people, and cases at a Madrid sauna.
U.K. officials have said "a notable proportion" of the cases in Britain and Europe have been among young men with no history of travel to Africa who are gay, bisexual or have sex with men.
Authorities in Portugal and Spain also said their cases were among men who mostly had sex with other men and whose infections were picked up when they sought help for lesions at sexual health clinics.
Officials need to better prepare gay community: experts
Some observers from the gay community have said public health officials are not doing enough to directly alert men who have sex with men about the risk of monkeypox.
"Many well-intentioned officials appear fearful of saying something homophobic, and news outlets have published articles emphasizing that monkeypox is 'not a gay disease,'" Jim Downs, a professor of the history of infectious diseases, recently argued in the Atlantic.
"Their caution is warranted, but health agencies are putting gay men at risk unless they prioritize them for interventions such as public-awareness campaigns, vaccines and tests."
As the month-long Pride celebrations begin, public health experts James Krellenstein, Joseph Osmundson and Keletso Makofane also said in a recent op-ed in the New York Times that health officials should be making bolder interventions to raise awareness of the disease and expand vaccine availability among men who have sex with men.
Citing the way public health officials mobilized to contain a bacterial meningitis outbreak in New York City a decade ago, these experts called for targeted solutions for the gay community.
"Health officials provided vaccines at nightlife spots and places where men meet for sex," they wrote. "As summer and Pride festivities near, we need similar approaches to help keep one another safe."