Health authorities in Spain reported on Friday 24 new confirmed cases of monkeypox, mainly in the Madrid region where the regional government closed a sauna linked to the majority of infections.
The total tally in Spain has now reached 30, while 23 confirmed cases have now been identified in neighbouring Portugal, where nine new cases were detected on Friday.
Madrid authorities have been working on tracing the cases mainly from a single outbreak in a sauna, regional health chief Enrique Ruiz Escudero told reporters on Friday. The word sauna is used in Spain to describe establishments popular with gay men looking for sex rather than just a bathhouse.
"The Public Health Department will carry out an even more detailed analysis... to control contagion, cut the chains of transmission and try to mitigate the transmission of this virus as much as possible," he said.
The Extremadura region confirmed its first case on Friday afternoon.
Another 18 suspected cases are under investigation in Spain, 15 in the Madrid region, two in the Canary Islands and one in Andalusia, the health authorities said.
More than 100 cases of the viral infection more common to west and central Africa have been now reported in Europe.
It is a usually mild infection, with symptoms including fever, headaches and a distinctive bumpy rash.
Twenty cases have been detected in Britain - where authorities are offering a smallpox vaccine to healthcare workers and others