Frimley Park Hospital has not been immune from mouse and insect infestation, figures released this week have shown.

But the hospital has one of the cleanest records in the country, with just 26 pest-control incidents reported in the past two years.

Figures obtained by the national Conservative Party using a Freedom of Information request have shown that more than two-thirds (70 per cent) of NHS trusts brought in pest controllers at least 50 times over the past two years to combat outbreaks of vermin in wards, clinics and even operating theatres.

The national figures show incidents involving rats, mice, ants and cockroaches, as well as other pests, between January 2006 and March this year.

James Taylor, Frimley Park’s communications manager, said: “We had 26 incidents which is quite low, and they included one incident of mice, which I believe was outside, ants, wasps, something called spider bird mites, silver fish and bees.

“None of the incidents have been in the catering areas.”

“The only thing that was in the main wards were ants, everything else has been outside.”

He added that pest controllers were always called in immediately and arrived promptly to deal with the problem.

The outbreaks across England and Wales included rats in maternity wards, wasps and fleas in neo-natal units and maggots in patients’ slippers.

All 171 NHS trusts in England were asked to detail pest infestations by the Conservatives. Of the 127 that responded, almost all said they had experienced some problems.

Vanessa Bourne, of national body the Patients Association, said: “These findings reveal what happens when money is taken away from where patients expect to see it spent. If these hospitals were restaurants they would be closed down and out of business. [NHS] trust boards must get a grip and show patients they are serious about their legal responsibility for safety.”