LONDON (AP) — A top adviser to the World Health Organization has described the unprecedented outbreak of the rare monkeypox disease in developed countries as “a random event” that could be explained by risky sexual behavior in two events recent massive in Europe.
In an interview with The Associated Press, Dr. David Heymann, a former head of the WHO emergency department, said the main theory to explain the spread of the disease was sexual transmission between gay and bisexual men at two raves in Spain. and Belgium. Monkeypox has not previously caused widespread outbreaks beyond Africa, where it is endemic in animals.
“We know that monkeypox can spread when there is close contact with the lesions of someone who is infected, and it appears that sexual contact has now amplified that transmission,” Heymann said.
That marks a significant departure from the typical pattern of disease spread in central and western Africa, where people are mainly infected by animals such as rodents and wild primates and outbreaks have not spread across borders.
To date, the WHO has recorded more than 90 cases of monkeypox in a dozen countries, including Britain, Spain, Israel, France, Switzerland, the United States and Australia.
Madrid’s top health official said Monday that the Spanish capital has recorded 30 confirmed cases so far. Enrique Ruiz Escudero said authorities are investigating possible links between a recent Gay Pride event in the Canary Islands, which drew some 80,000 people, and cases in a Madrid sauna.
Heymann chaired an urgent meeting of the WHO advisory group on infectious disease threats on Friday to assess the ongoing epidemic and said there was no evidence to suggest monkeypox might have mutated into a more infectious form.
Monkeypox usually 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 sheets, but sexual transmission has not yet been documented. Most people recover from the disease in several weeks without hospitalization. Vaccines against smallpox, a related disease, are also effective in preventing monkeypox, and some antiviral drugs are in development.
In recent years, the disease has been fatal in up to 6% of infections, but no deaths have been reported among current cases. The WHO said the confirmed cases so far have been of the less severe group of West African monkeypox viruses and appeared to be related to a virus that was first detected in cases exported from Nigeria to Britain, Israel and Singapore in 2018-2019.
The UN agency called the outbreak “a very unusual event” and said the fact that cases are being seen in so many different countries suggests the disease may have been spreading quietly for some time. The agency’s director in Europe 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 close contact related to sex that has driven the recent spread of monkeypox in Europe.
“By nature, sexual activity involves intimate contact, which one would expect to increase the likelihood of transmission, regardless of a person’s sexual orientation and mode of transmission,” said Mike Skinner, a virologist at Imperial College London.
On Sunday, Britain’s Health Security Agency’s top medical adviser, Dr. Susan Hopkins, said she expected more cases of monkeypox to be identified in the country “on a daily basis”.
UK authorities have said that “a notable proportion” of 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 men and whose infections were detected when they sought help for injuries 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 could be attributed to a single infection.
“It’s quite possible that there was someone who became infected, developed lesions on the genitals, hands or somewhere else, and then passed it on to others when there was close sexual or physical contact,” Heymann hypothesized. “And then there were these international events that seeded the outbreak around the world, in the US and other European countries.”
He stressed that the disease was unlikely to trigger widespread transmission.
“This is not COVID,” he said. “We need to slow it down, but it doesn’t spread in the air and we have vaccines to protect ourselves.” Heymann said studies must be done quickly to determine whether people without symptoms can spread monkeypox and that populations at risk of contracting the disease should take precautions to protect themselves.
Barry Hatton in Lisbon contributed to this report.