Portugal's legionnaires' disease outbreak is a "major public health emergency," the World Health Organization (WHO) warned on Tuesday.
The deadly legionnaires' disease is a type of pneumonia caused by the legionella bacteria, which can be transmitted through breathing mist from water containing the bacteria.
The UN health agency said the disease, which has killed five people in less than a week and affected around 235 people, was "the biggest Legionnaire's disease in Portugal."
Municipal water supply has been verified and is considered "safe," the statement added, though the Portuguese Ministry of Health has advised citizens to avoid showers and jacuzzis and to immerse shower-heads in bleach for 30 minutes at least once a week.
WHO described the legionnaires' outbreak as "unusual and unsuspected" and said the origin of the disease had not yet been discovered, but that the main refrigeration towers had been closed.
Portugal's Director-General of Health Francisco George said on Monday that all the cases reported have an epidemiological link with the outbreak which started in an area on the outskirts of the Portuguese capital Lisbon, in the neighboring town of Vila Franca Xira.