A ward at a hospital in North Lincolnshire has been closed to new admissions after a suspected outbreak of a diarrhoea and vomiting bug.
Northern Lincolnshire and Goole NHS Trust said ward 23 at Scunthorpe General Hospital had closed earlier.
It was carrying out tests to establish if the outbreak was caused by norovirus, the winter vomiting bug.
The hospital's two other wards, 16 and 17, were closed for several days last month due to a norovirus outbreak.
People suffering the symptoms have been urged not to come to the hospital "until they have been symptom free for 48 hours," the trust said.
Dr Peter Cowling, the trust's consultant microbiologist, said last month's outbreak was "a new strain of the virus for our region, which meant more staff were taken ill than would be expected".
"This outbreak on ward 23 is likely to be caused by the same virus," he said.
"Patients from the ward will not be discharged to nursing or residential homes while they remain an infection risk. We have closed the ward to new admissions."
He said regular disinfection was being carried out by the trust's infection prevention and control team to contain the outbreak.