And he is not a risk to them now he is back working in the hospital.

A spokesman said: “The patient was told that he could safely return to work because he had recovered from the illness and was no longer infectious.

“He had previously been treated as a suspected case and given antiviral medication. He responded well and recovered quickly

“It was unfortunate that the former patient was not given his positive result for H1N1 infection until after he had returned to work, and we are very sorry if this has caused some anxiety amongst fellow office workers.

“For this reason, we liaised with the hospital’s occupational health staff and asked them to reassure anyone with concerns that it is appropriate for their colleague to be back at work.”

Health officials said a further 142 cases of swine flu were confirmed yesterday through laboratory testing.

Of those, one patient was in Northern Ireland and the remaining 141 in England.

The Health Protection Agency said the cases included 124 in the West Midlands.

In addition, there were 71 new cases in Scotland yesterday, producing an overall UK total of 1,533.