Legionnaires' disease probe ends

The legionella bacteria is found in mist from contaminated water

An investigation by health officials into an outbreak of Legionnaires' disease which infected seven people in Norfolk last month has ended.

No source for the bug has been traced but authorities are confident the outbreak has ended.

Those infected, all men aged from their mid-30s to 70, responded to treatment in hospital and were later discharged.

Cooling towers in the Norwich area were chlorinated as a precaution, but they were not identified as the source.

Legionnaires' disease is most often contracted by inhaling mist containing legionella bacteria from water sources such as whirlpool baths, showers and cooling towers.

It cannot be passed from one person to another.

About 300 to 500 cases are reported each year in England with half associated with travel abroad.