Scarborough's Grand Hotel, splendidly perched on the cliffs of the North Yorkshire coast, has been forced to close after scores of people became ill with a virus.

The airborne virus, known as Norwalk, causes sickness and diarrhoea. So far, 191 have been affected; most are guests but 31 of them are hotel staff.

Four people were taken to hospital and one was kept in overnight. The hotel is closed until Monday for cleaning. The public health laboratory service described the risk of transmission of the virus as moderate to high.

Phil Kirby, a North Yorkshire public health consultant, said the Norwalk virus was a typical tummy bug that spread quickly in households where people were in close contact. Infected people felt unwell for 24 hours, and would be infectious for up to three days after the first outbreak of sickness.

The hotel has twice before been affected by the Norwalk virus, in 1994 and 1995.