The Gynae Ward at Altnagelvin closed to admissions on Monday (January 20) after an increase in vomiting and diarrhoea among patients.
Six patients and no staff had experienced such symptoms by late afternoon on Monday.
Another ward, Ward 8, which was closed for the same reason on Friday (January 17) reopened on Monday and was operating as normal.
Alan McKinney, Western Trust Medical Director said: “There is no direct relation between the closure of Ward 8 over the weekend and the closure of Ward 4 today. “When an increase in vomiting and diarrhoea is experienced in the community it can have an impact on hospital services and instances such as this are often the case at this time of year.
“The Trust’s Infection Prevention and Control team is continuing to provide advice and increased infection control measures have been taken.”
He continued: “The public has an important role to play by not visiting the hospital if they are feeling unwell, particularly if they have diarrhoea and/or vomiting. And if someone has been unwell we would advise them to wait until at least 72 hours after they have had diarrhoea and/or vomiting before visiting the hospital.
“Those who are visiting are asked to thoroughly wash their hands before and after visiting, for their own protection as well as for the prevention of the spread of infection to patients.
“Visitors are asked to limit visiting to the designated times of between 3pm and 4pm and from 7pm until 8.30pm.
“They should only visit the one patient whilst at the hospital and should not move from ward to ward when visiting.”