Four people have been hospitalised in Spain to try to stem the spread of Ebola after a Spanish nurse became the first person in the world known to have contracted the virus outside of Africa, health authorities said on Tuesday. The nurse, who tested positive for the virus on Monday, her husband, who is showing no symptoms of the disease, and two other people are being closely monitored in hospital, health officials said. One of those hospitalised is a health worker who has diarrhoea but no fever. The other is a Spaniard who travelled from Nigeria, said Rafael Perez-Santamaria, head of the Carlos III Hospital where the infected nurse treated two Spanish missionaries who contracted the disease in Africa.