The World Health Organisation (WHO) has said there have been 131 confirmed monkeypox cases and 106 further suspected cases since the first was reported on May 7 outside the countries where it usually spreads.
While the outbreak is unusual, it remains "containable" and limited, the WHO said on Tuesday, convening further meetings to support member states with advice on how to tackle the situation.
"We encourage you all to increase the surveillance of monkeypox to see where transmission levels are and understand where it is going," said Sylvie Briand, WHO director for Global Infectious Hazard Preparedness.
Speaking at the World Health Assembly in Geneva, Briand said it was unclear if the cases were the "tip of the iceberg" or if the peak of transmission had already passed.
She reiterated WHO's view that it is unlikely that the virus has mutated but said that transmission may be driven by a change in human behaviour, particularly as people return to socialising as Covid-19 curbs are lifted.
Slovenia reports first case
Slovenia reported on Tuesday its first case of monkeypox infection in a traveller who had returned from the Canary Islands in Spain, Slovenian N1 television reported. The man was reportedly not hospitalised.
Monkeypox is a usually mild viral infection that is endemic in parts of west and central Africa. It spreads chiefly through close contact, and until the recent outbreak has only rarely been seen in other parts of the world.
The majority of the recent cases have been reported in Europe. Symptoms include a fever and a distinctive bumpy rash.
The West African strain of monkeypox, which is the one identified in the current outbreak, has a mortality rate of around 1 percent.