The number of people diagnosed with Legionnaires disease in Stoke-on-Trent has risen to 19.
One person has died and nine others are being treated in hospital.
The Staffordshire Cluster of Primary Care Trusts say a hot tub display at the JTF Mega discount store in Fenton, Stoke On Trent is the probable source of the disease.
Click here to find out more about Legionnaires Disease.
People who contracted Legionnaires' disease this year are calling for a public inquiry after a fatal outbreak in Stoke-on-Trent.
A second person has died after an outbreak of Legionnaires disease in Stoke-on-Trent.
Officials believe the Legionnaires outbreak at Stoke On Trent can be traced to a hot tub in a Stoke warehouse.