A stark warning has been issued to beachgoers in Spain after a staggering 7,500 people required hospital treatment due to a surge of jellyfish, including the notorious Portuguese man o’war. The north-east coast of Spain, particularly Catalonia, has been severely affected, with rising sea temperatures being held responsible.

Since May this year, nearly 7,500 individuals on the Catalan coast have sought medical help for jellyfish stings, marking a significant 41 per cent increase from last…