Spain on Saturday reported its second monkeypox-related death, one day after announcing what is believed to be the first fatality linked to the current outbreak in Europe.

"Among the 3,750 patients... 120 have been hospitalised and two have died," the Spanish health ministry said in a report, without specifying the date of the second death.

The ministry told AFP an analysis will be carried out later to determine the cause of death.

According to the health ministry's emergency and alert coordination centre, 4,298 people in Spain have been infected, making it one of the world's hardest-hit countries.

The announcement came after Brazil also reported its first monkeypox-related death on Friday, with previous fatalities confined to Africa where the virus is endemic and was first detected in 1970.

It is unclear if monkeypox caused any of the three deaths, with Brazilian authorities saying its deceased patient suffered from other serious conditions.

The World Health Organization has declared the outbreak a global health emergency, the highest alert level it can sound.

Most infections are in Europe, where 70 percent of new cases have been detected since early May, according to WHO chief Tedros Adhanom Ghebreyesus.