Pest control officers were called out to NHS Tayside hospitals more than 900 times over the past two years the Tele can reveal.
Figures provided through Freedom of Information show that hospitals across Dundee, Perth and Angus had 925 visits from January 1 2018 until early December this year.
Ninewells Hospital had the most call-outs with 315. The second highest was Perth Royal Infirmary with 104.
The Royal Victoria Hospital had the third most with 89.
Other well known sites, such as Roxburghe House, had 12 reports and Stracathro Hospital had 45.
A total of 325 incidents were related to ants, while wasps resulted in the second highest number with 166 callouts.
Silverfish were next with 135. There were 54 callouts relating to rodents including mice and rats.
Nesting birds also proved problematic for health chiefs, with 68 mentions of pigeons, 10 seagulls, and 38 calls relating to birds in general.
A spokeswoman for NHS Tayside said: “NHS Tayside has strict procedures in place for dealing with pest control problems and all reports of a potential pest sighting are dealt with as a matter of urgency.
“Whenever a member of staff identifies any type of problem, no matter how small, our pest control contractors are called in straight away.
“All reports are dealt with as a matter of urgency to ensure there is no escalation of any problem and incidents are resolved quickly and effectively. This ensures there is little or no impact on clinical services.
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“It is important to note that our records show what is reported to the pest control company at the time of call-out and not necessarily what is found when they attend the site.”
Meanwhile, officers have been called out to Tayside schools hundreds of times since the beginning of the year.
Officers were called to schools in Dundee 56 times since January 1 this year, with 23 schools needing the service.
The school with the most incidents in Dundee was Braeview Academy with seven call outs to deal with issues including, wasps, mice, ants, and pigeons.
Ballumbie Primary was the second-highest number with six. Issues included bird proofing, ants, mice and pigeons.
Ants were the most frequent cause for calls, with 13 and mice second with 11.
Schools in Perth and Kinross had 163 callouts from January to November 20 this year, with Auchterarder Community School having the most at 18. The callouts at Auchterarder related to flies, mice, and ants.
Perth High School had the second highest number of incidents, with 12. Calls were in relation to ants, mice, wasps and slugs.
Callouts mentioning mice were the most common with 59 for schools in the Perth and Kinross area.
Ants were the second most common call out request, with 43 reports and wasps were mentioned 34 times.
Officers were called out 112 times to schools in Angus. The three schools with the most call outs were Arbroath Academy, Arbroath High School and Montrose Academy, with six each.
The highest number of callouts were for wasps with 34, and then there were 24 incidents relating to ants.
Other animals found at schools across the area included bees, silverfish, moles as well as a scorpion.
A Dundee City Council spokesman said: “The council monitors its buildings and any infestations that are discovered are dealt with quickly.”
An Angus Council spokesman said: “We respond promptly to any reported pest control issues within our schools and deal with them accordingly. Call-out volume varies year-on-year according to the weather.”
Perth and Kinross was approached for comment.