A third school in the Watford area has this afternoon confirmed that one of its pupils has contracted swine flu.

St Catherine of Siena Catholic Primary School has said a Year 3 student in the school has caught the virus.

However, after seeking advice from health experts, the school has decided to stay open.

A statement on the Garston school's website said: “There has been a case of swine flu in Year 3.

“We have taken advice from the local Health Protection Unit who have advised the school to remain open.

“Please be extra vigilant about any possible symptoms. If your child does display any signs of flu please keep them at home and inform the school immediately.”

The news follows the closure of Central Primary School, in Watford, today and Queens' School, in Bushey, on Tuesday.

Both schools have had confirmed cases of the bug, as well as dozens of pupils who have complained of flu symptoms. Queens' has confirmed 23 pupils have swine flu, although 141 were absent from school on Monday with flu-like symptoms.

Only one pupil is known to have tested positive for the H1N1 strain of the influenza virus at Central Primary School. However, many others could also have swine flu.

Headteacher, Melvyn Tatters, said around 30 pupils had complained they were feeling unwell today, with others phoning in sick.

Mr Tatters said members of staff at the school, some of whom have children at Queens', have also been feeling unwell.

He said: “I don't think it is ever easy to close a school. The main thing is to try to contain this as much as possible.

“I think parents have generally been understanding and because a local secondary school has closed because of swine flu they were aware it could spread to the children in the school.”

He said the school would reopen on Monday, July 6.