Cases of suspected and confirmed Monkeypox are being investigated in the US, Canada, Spain, Portugal and the UK, according to health authorities and local media reports.
Most recently one case was confirmed in the US and 13 suspected cases are being investigated in Canada.
Five infections have also been confirmed in Portugal as well as seven in Spain, health authorities say.
Monkeypox is most common in remote parts of Central and West Africa.
Cases of the disease outside of the region are often linked to travel to the area.
Monkeypox is a rare viral infection which is usually mild and from which most people recover in a few weeks, according to the UK’s National Health Service.
The virus does not spread easily between people and the risk to the wider public is said to be very low.
There are now nine confirmed cases in the UK. The source of these infections has not yet been confirmed but cases seem to have been “locally acquired”, the World Health Organization (WHO) says.
Confirmed cases have also been reported in Portugal and Spain after European health agencies were alerted to the reports in the UK.
And most recently, health authorities in the US state of Massachusetts confirmed that a man has been infected with Monkeypox.
He had recently travelled to Canada, where local media report that 13 suspected cases of the virus are being investigated.
According to health officials, the man has been hospitalised, is in “good condition” and “poses no risk to the public”.