The death is the second in the world outside of Africa, where so far five people have died in the current outbreak.
Earlier, the death of a person could also be related to monkeypox in Brazil, according to Reuters.
According to the latest statistics from Spanish authorities, around 4,300 cases of monkeypox have been confirmed in the country.
More than a hundred are said to have been treated in hospital.
Reuters reports that few people have become seriously ill from monkeypox, but that so far it has mainly affected men between the ages of 20 and 65.
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Photo: SVT/AP/CDC
The text is updated