Chesterfield Royal Hospital is urging visitors to stay away if they have experienced symptoms of Norovirus in the last two days
Norovirus is a stomach bug which causes vomiting and diarrhoea.
A spokesperson for Chesterfield Royal Hospital said: "If you have experienced Norovirus symptoms within the last 48 hours, do not visit the hospital.
"While it is an unpleasant virus for most people, for our inpatients with underlying health problems it can have much more serious consequences and even proved fatal.
"We don't want to close wards to visitors but need your help to prevent Norovirus spreading."