A spokesperson from NHS Greater Glasgow said: "There was a temporary problem with the supply of mops to the Victoria Infirmary earlier this week and we immediately addressed this by bringing in extra mops from a store supply at another hospital.
"We instantly prioritised the cleaning of key patient areas and the issue has now been fully resolved.
"A full investigation into how this happened is already well underway to ensure that steps can be taken to prevent this from happening again.
"No other hospitals were affected.
"Infection control is one of our top priorities and earlier this year our efforts were re-doubled with the launch of an awareness raising campaign aimed at staff, patients and visitors.The campaign also included the launch of a single citywide infection control manual giving clear guidelines for infection control measures across Glasgow's healthcares settings.Our infection control teams continue to work together to design initiatives to drive up standards."
"Over two weeks ago a rat was spotted in the corridor area outside ward 6 at the Victoria Infirmary. Measures were immediately taken to address this issue including thorough cleaning and a visit by pest control who took further precautions - there have been no further sightings since.
"Nearby building works are thought to be the cause of this isolated incident."
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