Fast-food provides a healthy diet for growing super-rats

Society/ year of the rodent

THEY thrived in the recession. They rely on fast-food restaurants. They've done well from water companies' privatisation and the cuts in local authority spending. They don't pay taxes, think global warming is good news and are growing steadily in numbers. Radical Conservatives? A new breed of yuppie? Nope. Rats.

According to a report published last week, rat infestation of homes in England and Wales has grown by 39 per cent since 1979. An average of one in 20 homes is infested, usually in the basement or garden. In the average suburban street, that means three or four houses. Yours, perhaps?

"There is a clear need for immediate action to control what is becoming an increasing problem," said Graham Jukes, director of professional services at the Chartered Institute of Environmental Health, which compiled the report with the Ministry of Agriculture, Food and Fisheries (MAFF) and the Central Science Laboratory. The study urges that a single government department should take overall responsibility for vermin control.

What the report was less keen to point out was the direct causes of the rise. But from talking to those in the pest control industry, it is quite clear that if rats and mice could vote, they would be Tories. This is quite separate from their role as carriers of salmonella, tapeworm, Weil's Disease (which damages the kidneys and liver, sometimes leading to jaundice, and is fatal in five to 10 per cent of cases), trichinosis, and the Plague. The truth is that Conservative policies have been a boon to rodents.

"Rats don't know when there's a recession on," says Richard Strand, executive director of the British Pest Control Association, whose members mainly provide professional services to companies.

"But the owners of properties do, because they can't afford to pay for someone to come in. During the recession a lot of companies would have turned to DIY methods to get rid of rat and mouse infestations. The trouble is, if they put down too small a dose, the rat or mouse might get ill, but recovers. From that they can learn - because they're smart - to avoid that bait in future. Then that bait doesn't work anymore."

This leads to populations of "super-rats" which appear to be immune to poisons, but in fact they are just passing it by, like wedding guests ignoring the egg mayonnaise on a hot day.

The growth of fast-food outlets has also been a boon to the population of the brown rat, rattus norvegicus, now the most common species - and their numbers find an interesting echo in the growth of McDonald's restaurants in Britain. The first opened in 1973, the 100th 10 years later, but the 300th only waited until 1988. By 1991 there were 400 outlets; by the end of 1994, 577. In that time the British rat population has risen to more than 60 million, outnumbering the human population.

While McDonald's is scrupulous about cleaning up inside and in the area around its restaurants, studies have found that people can walk up to a quarter of a mile from a fast-food outlet before dumping litter containing half-eaten scraps. To the rats, who tend to scavenge around a territory of about 300 square metres, that is close enough.

And where have they come from? Before the water companies' privatisation in the mid-1980s, many lived in sewers, which were the main focus for population control. But after privatisation, the companies shifted their investment towards improving the quality of water coming out of the taps, rather than worrying about what went down the plughole.

"The problem really comes when there's a fault in the sewer," says Mr Strand. "Then there's a terrible potential for them to get to the surface in large numbers." Once there, they benefit from two more hangovers of the 1980s: cuts in local authority spending - which led fewer and fewer councils to offer a free vermin control service - and inner-city decay, which offers former sewer-dwellers empty buildings, providing warmth and shelter.

But the Government cannot be blamed for everything. A succession of mild winters has also helped house and field mice. "Mice are probably a bigger public health threat," says Mr Strand. "Unlike rats, which can live outside the house, mice almost always live in the house, and usually just 6ft away from their food source. That means they are living in our kitchens." The average mouse sheds 80 droppings every day and urinates to mark its territory. They do not discriminate about whether that is on the sideboard or the food.

Mice infestations often go unnoticed, or even when they are noticed, are untreated.

Mr Jukes said: "The extent of the increase, and the fact that many infestations are not being treated, indicates that improved methods of control must be introduced and coordinated nationally."

It may be a vain hope. By the end of the week, the buck passing had begun. A MAFF spokesman said: "It wouldn't fall to MAFF to act on that recommendation. To a large extent this was an information exercise. It would fall to the Department of Health to implement any suggestions."