A man in his 70s who was being treated for Legionnaires' disease following a recent outbreak has died, the Health Protection Agency said.
The unnamed patient was being treated in hospital following the spate of confirmed illnesses, which are thought to have been instigated by a hot tub in City Road, Fenton, Stoke-on-Trent.
A spokesman for University Hospital of North Staffordshire said: "We can confirm that a man in his 70s has sadly died.
"Two further patients remain in hospital and are in a stable or improving condition."
The patient is the second to die after being affected by the illness.
The Health Protection Agency (HPA) said on July 28 that one of the patients affected by Legionnaires' had died in hospital.
The total of confirmed cases stands at 20, an HPA spokesman said.
It was revealed last week that the probable cause of the Stoke-on-Trent outbreak was a hot tub in the city after samples were found to have an unusual strain of legionella bacteria, which matched that of the strain taken from patients with the illness.
Dr Sue Ibbotson, regional director of HPA West Midlands, said the organisation has taken detailed histories from those with Legionnaires' and the majority of confirmed cases visited the warehouse in the two weeks before they fell ill.
The samples from the hot tub at JTF Warehouse were confirmed by the Health Protection Agency's specialist laboratory in Colindale last night as being the unusual strain legionella bacteria.
Dr Ibbotson warned that the number of cases of Legionnaires' disease could continue to rise because it can take up to two weeks following exposure for people to develop symptoms.