Three patients were infected with Legionnaires' disease at a hospital in the Hague. A 78-year-old woman died.
Tests were being carried out and the hospital's water system cleaned Tuesday after water samples in one shower block in the hospital showed traces of the bacteria that causes the disease, Haga Hospital said in a statement.
Legionnaires' disease, which got its name from an outbreak at an American Legion convention in 1976, is a form of pneumonia. Most people exposed to the bacteria never get sick, but the elderly and people with weak immune systems can be susceptible. The disease is treatable with antibiotics.
The unit where the four patients were infected has been closed since May 12, the statement said.
Local media said that one of the infected patients was being treated in intensive care, while the other two were recovering. A hospital spokesman could not be reached for comment.
The choice of the city of Helsinki is not incidental as the capital of Finland had hosted US-Soviet negotiations on the limitation of nuclear stockpiles in 1969