More than 1,000 cases of monkeypox have been reported to the World Health Organization during the current outbreak outside of countries in Africa where it is more likely to spread.
WHO Director-General Dr Tedros Adhanom Ghebreyesus said the risk of monkeypox establishing in these non-endemic countries was real, but currently preventable.
Twenty-nine countries have reported cases of the current outbreak, which began in May.
No one has reported deaths.
At a media briefing in Geneva, Tedros also said there were more than 1,400 suspected monkey pox cases in Africa and 66 deaths this year.
“It is an unfortunate reflection of the world we live in that the international community is only now paying attention to monkeypox because it has appeared in high-income countries,” he said.
He said the outbreak showed signs of community transmission in some countries.
The WHO advises to isolate people with monkeypox at home.
Rosamund Lewis, WHO technical leader on monkeypox, said that “close interpersonal contact” was the main way monkeypox spreads, although she added that the risk of aerosol transmission was not yet fully known.
Health workers caring for monkey pox patients should wear masks, she said.
Cases are still prevalent among men who have sex with men, the WHO added, although cases have been reported in women.
The United Nations agency is working with organizations including UN AIDS and community groups to raise awareness and stop the transmission.
Post-exposure vaccination, including for health professionals or close contacts, including sexual partners — ideally within four days of exposure — may be considered for some countries, the WHO added.
The vaccines used are designed against smallpox — a related more dangerous virus that wiped out the world in 1980, but also work to protect against monkey pox, studies have shown.
Sylvie Briand, senior WHO official, said the agency is evaluating the potency of smallpox vaccines and is contacting manufacturers and countries that have previously committed vaccines.