The World Health Organization (WHO) warned on Wednesday that the risk of monkeypox becoming established in non-endemic nations is real.
WHO chief Tedros Adhanom Ghebreyesus said the UN health agency was not recommending mass vaccination against the virus, and added that no deaths had been reported so far from the outbreaks.
"The risk of monkeypox becoming established in non-endemic countries is real," Tedros told a press conference, according to AFP.
"More than 1,000 confirmed cases of monkeypox have now been reported to WHO from 29 countries that are not endemic for the disease," Tedros added.
He noted that no deaths have been reported in these countries so far and that some countries are now beginning to report cases of apparent community transmission.
The initial symptoms include a high fever, swollen lymph nodes and a blistery chickenpox-like rash.
Tedros said he was particularly concerned about the risk the virus poses to vulnerable groups, including pregnant women and children.
Two weeks ago, a top World Health Organization (WHO) official said the WHO does not believe the monkeypox outbreak outside of Africa requires mass vaccinations.
Richard Pebody, who leads the high-threat pathogen team at WHO Europe, told Reuters that immediate supplies of vaccines and antivirals are relatively limited.
In Israel, three cases of monkeypox have been discovered so far, the latest case being confirmed on Tuesday.
The Health Ministry said the patient is a 34-year-old man who arrived at Ichilov Hospital in Tel Aviv with symptoms suspected to be from monkeypox after returning from a trip abroad. He was confirmed to have monkeypox after an examination by the Biological Institute.
Meanwhile, the US Centers for Disease Control and Prevention (CDC) has issued an "Alert -- Level 2" advisory for travelers to "practice enhanced precautions" because of the spread of monkeypox.