The 68 cooling towers housed in 28 buildings were inspected, cleaned and disinfected, but the operation has not put an end to the epidemic.
The disease, which poses a risk for people with weak immune systems, can be treated with antibiotics.
Legionnaire's disease – discovered in 1976 during a veterans convention in the United States, where 29 people died – is an infection that causes high fever, dry cough and pneumonia.
Source: agencies
