HEALTH experts are advising people to be on the look out for the symptons of an infectious vomiting disease.

The Health Protection Agency and Greenwich Teaching Primary Care Trust are urging people to stay away from crowded places, especially hospitals and schools, if known to be infected with norovirus.

The infection, which occurs mainly in the winter, causes projectile vomiting and diarrhoea.

If the infection is brought into hospitals it can result in wards needing to be closed.

Dr Rachel Heathcock from the south east London Health Protection Unit said: "We are already seeing cases of norovirus locally.

"It is important to be vigilant and good hygiene is essential in preventing yourself or others from picking up the infection.

"Hand washing is especially important, after using the toilet and before eating, and after an episode of illness any contaminated surface should be thoroughly disinfected."

According to the HPA and Greenwich Teaching PCT, to prevent passing on norovirus to others, you should stay away from work or school for two days after your symptoms have ceased.

If you have been unwell with norovirus for more than three days you should contact your GP.

Anyone who is worried about norovirus should contact their GP or call NHS Direct on 0845 4647