Dr Rita Robertson said the treatment was a purely precautionary measure
Sixty-five staff and pupils at a primary school in Cheshire are being given antiviral drugs after a four-year-old pupil contracted swine flu.
The child developed symptoms while attending the nursery attached to Grappenhall Heys Primary School, in Grappenhall, Warrington.
Warrington Primary Care Trust (PCT) said the school would remain open and pupils could continue attend as normal.
A 40-year-old man, a close relative of the child, has also tested positive.
News of the town's first cases of the virus emerged after the first UK death, in Scotland.
Warrington PCT said the child and relative were making a "good recovery" at home.
Both are being treated with antivirals, as are other close contacts and family members, the PCT said.
"It is understood that the child caught the virus from a confirmed case which contracted the infection abroad and has no association with the school," a spokesperson said.
"As a precautionary measure 65 children and staff who had significant contact with the child are being given antiviral medication and can continue to attend school as normal, unless they develop flu-like symptoms."
Headteacher Davina Woods said the school had worked hard to take precautionary measures, but that it was "business as usual".
Ms Woods said: "Parents have been reassured by our swift action and we had a special assembly this morning to teach children about the importance of good handwashing and 'safe sneezing', so everyone is well aware of what they need to do to minimise the spread of infection.
"We have acted on advice from the Health Protection Agency to keep the school open and we will keep this under constant review."
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