(Bloomberg) -- New and suspected cases of monkeypox have cropped up in New York City, Sweden, Canada and the two biggest cities in Australia in recent days, in signs that the rare and potentially deadly cousin of the smallpox virus traditionally confined to regions in Africa is now seeded across the globe. 

Scientists are hunting for links between the scattered infections that have been emerging in the northern hemisphere for about two weeks now. The pathogen typically causes flu-like symptoms, followed by a rash that often starts on the face and spreads down the body. The illness often lasts for two weeks to a month.

The virus doesn’t spread efficiently between people since direct contact with bodily fluids, infectious sores, contaminated material or large respiratory droplets is needed for transmission. But the danger of even rare occurrences is apparent in how widely the virus has now traveled, with cases popping up in many corners of the world. 

The rising infections may be a complication tied to one of the greatest human victories ever over disease, said Anne Rimoin, chair of infectious diseases and public health at the University of California, Los Angeles. 

“The eradication of smallpox was one of the greatest achievements in human health and public health history,” she said. “But, of course, it’s left the world without immunity to pox viruses. It’s not surprising to start to see more cases occur when people are exposed.”

Monkeypox is significantly less dangerous than smallpox, though it can still be fatal. The strain that’s currently circulating is believed to kill about 1% of those infected. 

Experts from the medical and financial worlds said the risk to global health remains low since the virus doesn’t spread easily and containment measures are generally effective, particularly when compared to Covid-19.

“We’re cautiously optimistic about risk,” said Jonathan Miller, an analyst at Evercore ISI in New York. “Monkeypox incubation is commonly about nine to 10 days. Slower-moving infection makes a disease easier to contain and gives docs more time to respond in course of an infection.”

About a dozen outbreaks of monkeypox have been identified in Africa since the 1970s. While authorities still haven’t identified the reservoir where the pathogen lays in wait between flareups, they believe rodents and small mammals in Africa help spread it to other animals and humans, according to the US Centers for Disease Control and Prevention.

Australia’s first case was diagnosed in a man in his 30s who developed mild symptoms while visiting the UK, before he returned to Melbourne. Another probable case was detected in a man in his 40s, who developed a mild illness after returning to Sydney from Europe. 

The first case in the U.S. this year was identified in a Massachusetts man who had recently traveled to Canada, where authorities are investigating up to 13 cases in Montreal, according to media reports. Another possible case is being investigated in New York City, while two more infections have been reported in the UK, bringing the total there to nine.

Other possible or confirmed cases have been reported in Spain, Portugal, France, Italy and Sweden. 

©2022 Bloomberg L.P.