A ward at Caithness General Hospital has been closed to new admissions after an outbreak of sickness and diarrhoea.
Bignold Wing currently has seven patients affected and samples have shown that the winter vomiting virus norovirus is present in the ward.
Visitors are being asked to stay away while staff deal with the cases of sickness.
The virus, which causes diarrhoea, nausea and vomiting, spreads in the air and is extremely infectious.
The hospital has warned that it is important that everyone plays their part in reducing outbreak risks.
Dr Adam Brown, consultant microbiologist at NHS Highland, said: “By closing the ward to new admissions and restricting visiting to the affected areas it helps our staff protect the health, privacy and dignity of our patients.
“We would also ask that people do not come to the hospital to visit if they have, or live with someone who has had any vomiting or diarrhoea within the previous 48 hours. By doing this we will be able to limit the spread as much as possible.
“Hospital staff will of course be very happy to talk to visitors on the phone so they can get updates on how their relatives are.”
If anyone feels that visiting is essential then they should contact the ward first by phone before going to the hospital.
There is no specific treatment for a norovirus infection and it is not usually necessary to visit a doctor.
The best course of action is to stay at home and drink plenty of water to prevent dehydration.
People should also adhere to strict hand washing techniques to reduce the spread of the virus.