Jose Ramon Arribas, Infection Unit Chief at Madrid's La Paz-Carlos III hospital, reacts during a news conference in Madrid October 7, 2014. 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 told a news conference in Madrid. REUTERS/Susana Vera (SPAIN - Tags: HEALTH SOCIETY DISASTER)