Three wards at Bradford Royal Infirmary remained closed today following an outbreak of a sickness bug.

Staff and patients at the hospital are believed to have been struck down with the bug - known as norovirus - and scores more people in the community are thought to be suffering.

Medical experts at the West Yorkshire Heath Protection Unit (HPU) have warned there is a larger risk of catching the bug in environments where groups of people congregate, such as hospitals, nursing homes and schools.

As reported in the T&A, wards at Bradford Royal Infirmary were closed at the start of the week.

Visitors are still being told to stay away from wards seven, one and 22, but a ward at St Luke's Hospital has reopened.

A spokesman said: "This is a common virus in winter and we are working hard to keep it under control."

Airedale Hospital has not been hit by the bug, a spokesman said.

The number of children in schools and nurseries suffering from the symptoms of the gastrointestinal is also believed to have fallen slightly.

A spokesman for the HPU said that it was also aware of outbreaks at nursing homes in Bradford district.

At the start of the week, nine primary schools and nurseries in the district reported increased incidents of sickness.

St Anthony's in Clayton, St Matthews in Allerton and Keighley Community Nursery have been taken off the list of affected schools, a Bradford Council spokesman said.

Margaret MacMillan Primary in Manningham, St Oswalds Primary in Great Horton, Bowling Park Primary and Frizinghall Primary, were still out of bounds to most visitors yesterday.

Also added to the list are Abbey Green Nursery and Hollingwood Primary.

Others that have been affected include Midland Road Nursery in Manningham, Lapage Primary in Barkerend Road.

John Major, Bradford Council's assistant director for environmental health, said: "Where children are suffering from norovirus, or winter vomiting, as it is commonly known, it is important that parents do not send them back to school until at least 48 hours after they are well and symptom free."