WARDS have been closed in five Scottish hospitals because of an outbreak of the vomiting bug norovirus.

Health Protection Scotland (HPS), which monitors the illness, announced the official start of the norovirus season yesterday because of the level of spread in the NHS.

The latest snapshot shows three wards closed by NHS Greater Glasgow and Clyde, two in NHS Lanarkshire, one in Grampian and one in Lothian.

In total, 42 patients on these wards have fallen ill with the symptoms of sickness and diarrhoea.

Last year the norovirus season started earlier in the autumn and Health Secretary Alex Neil has repeatedly blamed the bug for the struggle hospitals experienced coping with the number of patients who needed beds last winter.

Hundreds of people had to wait more than 12 hours in accident and emergency departments because there was not enough space to admit them to wards.

HPS said although this year the norovirus season has started later it does not necessarily mean there will be fewer outbreaks. Dr Evonne Curran, infection control nurse consultant for HPS, said: "Although it started late, it can still do some damage. This is the time to ensure advice notices are up, policies are ready and everyone is thinking about what can happen and make sure they have the resources."

Jason Long, Scottish chairman of the College of Emergency Medicine, said hospitals are getting busier compared to the summer months but appear to be coping better than they did a year ago.

He said: "There are still challenging areas. On the whole it seems to be that the plans we put in place seem to be helping.

"That does not mean there are not some days that people are experiencing that are hard. We know we have not completely solved things."

Delays of 12 hours in A&Es do not seem to be a problem at the moment, he added. The Scottish Government released £9 million to boards to support winter planning this year - three times the amount provided last year.

Norovirus is a highly infectious virus that triggers outbreaks in community and health settings and, like flu, causes surges in illness every winter.

This year a publicity campaign was launched urging anyone suffering the symptoms to stay at home for 48 hours after their symptoms have stopped and to avoid care homes and hospitals.

It also advises frequent hand washing with soap, particularly after using the toilet and before eating or preparing food.

Norovirus is usually unpleasant rather than dangerous, but it can be a more serious bug for people who are already unwell.

HPS is currently collating the latest information about the incidence of norovirus but Dr Curran said it is not becoming more widespread.

She added: "We could be heading for something very quiet or it could be that it is just about to suddenly kick off.

"We have got to give it a few more weeks to tell."

Levels of norovirus in England have also been low so far this winter.