A Birmingham hospital called in environmental health officers after it found an infestation of mice in a cleaning area.
City Hospital on Dudley Road treated a room this week only five months after the main kitchen was forced to shut for a day after evidence of "mice activity" was found.
Council officers inspected an area of the hospital where crockery is cleaned for a staff and visitors canteen on Wednesday after being contacted by concerned staff.
The hospital said it subsequently launched an action plan to treat the infestation which has proved successful.
A spokeswoman for Sandwell and West Birmingham Hospitals Trust said "stringent procedures" have been put in place for pest management.
She added: "We contacted Birmingham City Council?s Environmental Health Officer earlier this week, following concerns of mice activity in one pot wash room.
"Following this visit an agreed programme of work and monitoring was put in place, which has revealed no further activity.
"In September 2005 activity was sighted during an inspection of the kitchen at City Hospital and we worked with the Environmental Health Officer to rectify the situation.
"The main kitchen was closed for one day while this issue was being dealt with and a contingency plan for food provision was put in place."
The pot wash room is separate from the room used for patient meals. No activity was found in any patient area, the spokeswoman added.
A spokesperson for Birmingham City Council said: "City Hospital contacted us asking for hygiene advice.
"Upon visiting the site our officer found only minimal evidence of mice activity in one pot wash room.
"No evidence was found in any areas relating to either patient care or food preparation. We advised the hospital accordingly on dealing with the situation."