A leading adviser to the World Health Organisation described the unprecedented outbreak of monkeypox in developed countries as “a random event” that might be explained by sexual behaviour at two recent raves in Europe.
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 at 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 Dr 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.
Health officials say most of the known cases in Europe have been among men who have sex with men, but anyone can be infected through close contact with a sick person, their clothing or bedsheets.
Scientists say it will be difficult to disentangle whether the spread is being driven by sex or merely close contact.
The WHO has recorded more than 90 cases of monkeypox in a dozen countries including the UK, Canada, Spain, Israel, France, Switzerland, the US and Australia.
The cases so far have been mild, with no deaths reported.
Typically, the virus causes fever, chills, rash and lesions on the face or genitals. Most people recover within several weeks without requiring hospitalisation.
Meanwhile, an old vaccine, which many countries are stocking up on to protect against the monkeypox virus, is still under consideration by an expert group overseeing the infection in Ireland, it emerged yesterday. The smallpox vaccine is in demand again because it can provide up to 85pc protection against the monkeypox virus.
Asked if Ireland is following the lead of other countries and purchasing the vaccine, the HSE said the incident team is “considering advice on vaccines and counter-measures”.
Ireland has had no reported cases of monkeypox so far.