Monkeypox explained: What this rare disease is, where it’s spreading, why it’s called that

Health authorities in Europe, North America, Israel and Australia have identified more than 100 cases of monkeypox in recent days.

They say the risk to the general population is low. But they’re keeping close tabs because, for the first time, the rare disease appears to be spreading among people who didn’t travel to Africa, where monkeypox is endemic.

WHAT IS MONKEYPOX?

The virus originates in wild animals like rodents and primates and occasionally jumps to people. It belongs to the same virus family as smallpox.

Most human cases have been in central Africa and west Africa. Outbreaks have been relatively limited.

The illness was first identified by scientists in 1958, when there were two outbreaks of a “pox-like” disease in research monkeys — thus the name monkeypox.

The first known human infection was in 1970, in a young boy in a remote part of Congo.

WHAT CAUSED THIS LATEST OUTBREAK?

A top adviser to the World Health Organization says the leading theory is that monkeypox was spread after sexual activity at two recent raves in Europe.

Dr. David Heymann, who chairs WHO’s expert advisory group on infectious hazards, said monkeypox can spread when there’s close contact with someone infected with the disease and that “it looks like sexual contact has now amplified that transmission.”

Authorities say most of the known cases in Europe have been among men who have sex with men, but experts say anyone can get the virus through close contact with a sick person, their clothing or bedsheets.

“This may just be unlucky that it happened to get into this one particular community first,” said Dr. Jake Dunning, an infectious diseases researcher at the University of Oxford. “It’s just that they are a community, and, by having sex with each other, that is how it’s spreading.”

Scientists say it will be difficult to determine whether the spread is driven by sex or merely close contact.

WHAT ARE SYMPTOMS, TREATMENT?

Most monkeypox patients experience fever, body aches, chills and fatigue. People with more serious illness can develop a rash and lesions on the face and hands that can spread.

Most people recover within two to four weeks without needing to be hospitalized. But monkeypox can be fatal for up to 6% of cases and is thought to be more severe in children.

Smallpox vaccines are effective against monkeypox. Anti-viral drugs also are being developed.

The European Centre for Disease Prevention and Control recommended that all suspected cases be isolated and that high-risk contacts be offered a smallpox vaccine.

Britain is offering high-risk contacts the smallpox vaccine and recommending that people who might be infected isolate until they recover.

The United States has 1,000 doses of a vaccine approved for the prevention of monkeypox and smallpox plus more than 100 million doses of an older-generation smallpox vaccine in a government stockpile, officials said.

HOW WORRYING IS THIS OUTBREAK?

Any outbreak of an emerging virus is concerning, but most of the cases have been mild. And there have been no deaths.

Monkeypox requires very close contact to spread, so it isn’t likely to prompt big waves of disease like COVID-19, which can be transmitted in the air by people with no symptoms.

Still, Britain’s Health Security Agency has said it expects to see new infections “on a daily basis.” And WHO’s Europe director warned that the summer season of festivals and parties could spread the disease.

HOW COMMON IS MONKEYPOX NORMALLY?

The World Health Organization estimates there are thousands of monkeypox infections in about a dozen African countries every year. Most are in Congo, which reports about 6,000 cases annually, and Nigeria, with about 3,000 cases.

In the past, isolated cases of monkeypox have been spotted outside Africa, including in the United States and Britain, largely linked to travel in Africa or contact with animals from areas where the disease is more common.

In 2003, 47 people in six U.S. states had confirmed or probable cases. They caught the virus from pet prairie dogs that been housed near imported small mammals from Ghana.