Rentokil is to field high-tech weaponry in its battle against rats and mice after saying that climate change and Britain’s rubbish-strewn streets have fuelled the busiest July for its pest control business in a decade.

The group said yesterday that it was developing a range of “James Bond-style technology”, including infrared detection systems, after signs that the rodent population is rising at an alarming rate.

Calls from worried homeowners wanting Rentokil to track down and kill off mice surged 385 per cent last month in London and the South East. Across the country, requests for the removal of wasp nests rose by 120 per cent.

The details came as Doug Flynn, Rentokil chief executive, revealed the first signs that the group, which also operates in parcel delivery, textile cleaning and washroom servicing, was emerging from a four-year slump.

Underlying half-year pretax profits fell 12.9 per cent to £88.6 million in the six months to June 30 as a higher interest bill and lower margins offset revenue growth of 23 per cent. However, Mr Flynn said that operating profits in the second quarter were 11.1 per cent higher than a year ago and should continue to grow strongly.

He is targeting mid-to-high single digit growth at the pretax level in 2008. He said: “We believe the group passed an inflection point in terms of profits at the end of the first half.

“There is a light at the end of the tunnel, and there’s no sign of a train coming towards us, either.”

Experts believe that the rat population has grown by 39 per cent in the past seven years and could be as high as 100 million. The summer rat population is up by nearly 70 per cent since 1999, according to the National Pest Technicians Association.

The switch by 144 local authorities in England and Wales to fortnightly rubbish collections and cutbacks in their own pest control operations have contributed to the problem, the company said.

Jed Kenrick, managing director of Rentokil’s UK pest control business, said it was clear that the number of rats and mice was growing at a significant rate. He blamed climate change and the fact that bin bags were being left on the street for far longer.

He added that water companies were also partly to blame for reducing baiting in sewers. This meant that the underground population of rodents and vermin was “burgeoning”.

He said: “We did have a big contract win in July, and that obviously helped our figures, but there was also just a huge rise in the number of calls.

“There is more rubbish on the street, discarded burger and kebab boxes, and bins are not collected as often.

“But there’s also the weather. The milder winter means more wasps, rats and mice are surviving, and with the wet weather mice are more likely to seek shelter in the home.

“You have to remember as well that our perception of the problem is increasing. Our standards of cleanliness are getting higher all the time.”

Rentokil shares, which entered the FTSE 100 index yesterday in place of Hanson, closed down 1¾p at 171¼p. They had gained 14 per cent this month on expectations of an upturn over the remainder of the year.

Marc Van’T Sant, an analyst at Citi-group, said Rentokil appeared to be feeling more confident than at any time since Sir Clive Thompson, the former chairman, ran the business.

He added, however: “The bottom line is we do not expect material changes to consensus forecasts on the back of today’s release.”

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