Health chiefs were again asking people to steer clear of East Surrey Hospital, Redhill, this week as the latest outbreak of winter vomiting disease continues there.

Surrey and Sussex Healthcare NHS Trust, which runs the hospital, was advising people with the vomiting and diarrhoea bug, also known as norovirus, to stay away from the hospital until 48 hours after their symptoms had stopped.

Last week, the East Surrey saw what a spokesman called “a dramatic increase” overnight in cases of the bug, which is the most common cause of infectious gastroenteritis - diarrhoea and vomiting - in England and Wales. At the time, a Trust spokeswoman said she was unable to confirm the number of cases but said nine wards had been affected by the outbreak, with some bays closed, but no wards closed and no wards set aside specifically for norovirus cases.

Extra precautions were put in place to protect the hospital's patients and to help stop the spread of the bug.

Visiting was restricted to an immediate family member only, and the hours were restricted to 2pm to 3pm and 7pm to 8pm. As children often pose a high infection risk, the Trust was urging parents to carefully consider the risk to patients before taking children to visit a relative at the hospital. This week, as Life went to press, a spokesman said the norovirus bug had affected several wards, but after a week of stringent infection control measures, the majority of patients were clear of symptoms.

Though sudden and involving projectile vomiting, the illness is generally mild and people usually recover fully within two to three days. There are no long-term effects from being infected but infections can occur at any age because immunity is not long lasting. Stressing the continuing message to people with the bug to stay away from the hospital, Sally Britain, acting chief nurse of Surrey and Sussex Healthcare NHS Trust, said: “Norovirus can cause serious disruption in hospitals at this time of year.

“We work incredibly hard to ensure that infections can’t spread from patient to patient, or ward to ward, but all these efforts can be undone by someone who comes into hospital as a visitor or patient while they are still carrying a bug such as norovirus.”

A Trust spokesman said anyone with diarrhoea and/or vomiting should not visit the hospital unless instructed to do so by their GP, and should seek medical advice from their GP.

The spokesman said people with the bug should stay at home, drink plenty of fluids to avoid dehydration, wash their hands and clean toilets regularly to prevent spreading, and call their GP if they have concerns. Earlier this year, an outbreak of the bug prompted bed closures in some areas of the hospital and similar warnings to hospital visitors.

An outbreak last year laid low more than 20 people across four wards, with some areas closed to new patients, but no wards having to be closed.

In December 2008 and January 2009, the norovirus hit the hospital with 50 people falling ill in the first wave, and two wards being shut to incoming patients. In a resurgence about two weeks later, 18 more patients fell ill in four days.