County Hall officials have said the spread of swine flu through Watford's schools will be dealt with on a “case by case” basis.

Three schools in the Watford area have now been confirmed to have students with the virus. Two schools – Queens' School, in Bushey, and Central Primary School, in Watford – have been forced to close.

One pupil at St Catherine of Siena School Catholic Primary School, in Garstson, has also contracted the bug. However, the school has opted to stay open on the advice of the Health Protection Unit.

In a statement from Hertfordshire County Council, officials say the spread of the virus would be dealt with on a school by school basis.

The statement read: “Hertfordshire Primary Care Trust is reporting a steady increase in the number of confirmed cases of swine flu in Hertfordshire.

“Some schools have been affected and the county council is continuing to monitor the situation closely.

“Confirmed cases in schools are being dealt with on a case-by- case basis, with advice provided by the Health Protection Agency and the local Primary Care Trust.

“It is important to remember that the majority of cases in the UK are mild and that people seem to be recovering well.”

It added: “As one of Hertfordshire's biggest employers, we are fully prepared for our own employees to be affected by the virus and have plans in place to keep our services running smoothly.

“We are liaising with other organisations in the county and the eastern region to ensure that our efforts are co-ordinated.”