A health worker at a Derby hospital has been diagnosed with swine flu, health officials have confirmed.
Five others, who were working closely with the employee, were sent home with antiviral tablets and are awaiting test results to see if they have the virus.
Officials will not confirm which hospital the health worker is based at.
But Em Wilkinson-Brice of the Derby Hospitals NHS Foundation Trust said the virus was contained and the risk to patients and visitors was minimal.
She said: "I think what's really important is that the public don't be concerned or anxious that there's there's any great risk for them...
"Really you're looking at somebody who has been in sustained contact with another person who's got swine flu for over an hour and really in quite close proximity so sort of less than a metre."
She said they had been working closely with the Health Protection Agency (HPA) and local healthcare services to develop robust plans to deal with cases of swine flu.
The virus emerged in Mexico and is now officially the first flu pandemic for 40 years.
Swine flu is a respiratory disease, caused by a strain of the influenza type A virus known as H1N1.