Monkeypox likely spread by sex at two raves in Europe, expert says

Microscope image of monkeypox virions
A leading doctor who chairs a World Health Organization expert group says the outbreak of monkeypox in developed countries is “a random event.”
(Cynthia S. Goldsmith, Russell Regner / CDC)

A leading advisor to the World Health Organization described the unprecedented outbreak of the rare disease monkeypox in developed countries as “a random event” that might be explained by risky sexual behavior at two recent mass events in Europe.

In an interview with the Associated Press, Dr. David Heymann, who formerly headed the WHO’s emergencies department, said the leading theory to explain the spread of the disease was sexual transmission among gay and bisexual men at two raves held in Spain and Belgium. Monkeypox has not previously triggered widespread outbreaks beyond Africa, where it is endemic in animals.

“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.


That marks a significant departure from the disease’s typical pattern of spread in central and western Africa, where people are mainly infected by animals like wild rodents and primates and outbreaks have not spilled across borders.

A German government report to lawmakers, obtained by the AP, said that it expected to see further cases and that the risk of catching monkeypox “mainly appears to lie with sexual contacts among men.”

The four confirmed cases in Germany have been linked to exposure at “party events including on Gran Canaria and in Berlin, where sexual activity took place,” it said.

Monkeypox is garnering increased attention because outbreaks and cases are showing up in areas where they don’t usually occur.

May 20, 2022

To date, the WHO has recorded more than 90 cases of monkeypox in a dozen countries, including Britain, Spain, Israel, France, Switzerland, the U.S. and Australia. On Monday, Denmark announced its first case, Portugal revised its total upward to 37 and Italy reported an additional infection.

Madrid’s senior health official said Monday that the Spanish capital had recorded 30 confirmed cases so far. Enrique Ruiz Escudero said authorities were investigating possible links between a recent gay pride event in the Canary Islands, which drew some 80,000 people, and cases at a Madrid sauna.

Heymann chaired an urgent meeting of the WHO’s advisory group on infectious-disease threats Friday to assess the ongoing outbreak and said there was no evidence to suggest that monkeypox might have mutated into a more infectious form.


Monkeypox typically causes fever, chills, rash and lesions on the face or genitals. It can be spread through close contact with an infected person or their clothing or bedsheets, but sexual transmission has not yet been documented. Most people recover from the disease within several weeks without requiring hospitalization.

U.S. and European health officials identify a number of cases of monkeypox, an illness previously limited mostly to central and western Africa.

May 19, 2022

Vaccines against smallpox, a related disease, are also effective in preventing monkeypox, and some antiviral drugs are being developed.

In recent years, the disease has been fatal in up to 6% of infections, but no deaths have been reported among the current cases. The WHO said confirmed cases have so far been the less-severe West African group of monkeypox viruses and appeared to be linked to a virus that was first detected in cases exported from Nigeria to Britain, Israel and Singapore in 2018-19.

The U.N. agency called the outbreak “a highly unusual event” and said the fact that cases are being seen in so many different countries suggests that the disease may have been silently spreading for some time. The agency’s Europe director warned that as summer begins across the continent, mass gatherings, festivals and parties could accelerate the spread of monkeypox.

Other scientists have pointed out that it will be difficult to disentangle whether it is sex itself or the close contact related to sex that has driven the recent spread of monkeypox across Europe.

“By nature, sexual activity involves intimate contact, which one would expect to increase the likelihood of transmission, whatever a person’s sexual orientation and irrespective of the mode of transmission,” said Mike Skinner, a virologist at Imperial College London.

On Sunday, the chief medical advisor to Britain’s Health Security Agency, Dr. Susan Hopkins, said she expected more monkeypox cases to be identified in the country “on a daily basis.”

British officials have said “a notable proportion” of the cases in Britain and Europe have been in young men with no history of travel to Africa and who are gay, bisexual or have sex with men. Authorities in Portugal and Spain also said their cases were in men who mostly had sex with other men and whose infections were picked up when they sought help for lesions at sexual health clinics.

Heymann, who is also a professor of infectious diseases at the London School of Hygiene and Tropical Medicine, said the monkeypox outbreak was likely a random event that might be traceable to a single infection.

Massachusetts has reported a case of monkeypox in a man who recently traveled to Canada.

May 18, 2022

“It’s very possible there was somebody who got infected, developed lesions on the genitals, hands or somewhere else, and then spread it to others when there was sexual or close physical contact,” Heymann said. “And then there were these international events that seeded the outbreak around the world, into the U.S. and other European countries.”

He emphasized that the disease was unlikely to trigger widespread transmission.

“This is not COVID,” he said. “We need to slow it down, but it does not spread in the air, and we have vaccines to protect against it.”


Heymann said that studies should be conducted rapidly to determine if monkeypox could be spread by people without symptoms and that populations at risk of the disease should take precautions to protect themselves.