Have you got a mouse about the house

Mus domesticus

You have Well, lucky, lucky you! No wonder Walt Disney chose this sweet, shy, moustache-twitching little furry fellow as his inspiration for Mickey Superstar. And we've all been charmed, as children, by Beatrix Potter's tales of Johnny Town-mouse and his friends.

Are we leading up to something nasty

Playing host to a house mouse (mus domesticus) is not all as cosy as the Disneys and Potters persuaded us to believe. (True, Potter's country mouse, Timmy Willie, had to run for his life from poker-brandishing housemaid Sarah. But when he fell through a hole in the skirting-board, there down below, enjoying a relaxed, townie-type meal, presumably unsuspected by the humans up above, lounged Johnny Town-mouse and his dinner guests). Swe-eeeeeet!

Sarah, presumably, just put away her poker and thought little more about the house mouse. Bad move. Because fast-breeding domestic mice are a bundle of menaces to human life and health'

What kind of "menaces"

Disease, for a start: weils, hantavirus, listeria, salmonella, toxicara, to name but several.

Dangerous dirt: a house mouse leaves a trail of disease-ridden urine and droppings, wherever he goes. On the kitchen floor. Up on the chopping board. Inside the bread bin that's never quite shut.

Damage to property: mus domesticus won't necessarily stop at gnawing holes in your new leather sofa. He's just as likely to nibble at electric cables. And that, surprisingly often, can get the happy home burned to the ground.

OK, so where do mice prefer to live

Once inside the house, your adventurous mouse will make for a likely nesting place ' under the floor, in the airing cupboard, up in the loft, inside an armchair or sofa (no way into that sofa No worries: he'll just gnaw his way through).

Mice navigate pipes, cables and ducts ' and shoot straight up walls.

We've checked around ' can't see how a mouse would get in

Better check again. Not many holes and cavities are too small for a house mouse to squeeze through. His particular body structure means he can use the most unlikely-looking space: a 6-millimetre (quarter-inch) gap can be enough.

Look hard enough and you'll probably soon spot one or two of those "unlikely" access holes. Then it's time to check for other clues to a possible invader. The droppings, for a start: tiny grains of "black rice". The smell and stains of urine. The grease marks around a hole in (for example) a skirting board. And, of course, mysterious bits of damage. When everything's very quiet, you may even hear the sound of gnawing.

How DO we get rid of the damn things, then

A cat, of course, is supposed to be your best watchdog. But don't bet on it.

The other methods are traps or some sort of poison. Neither is a good idea if there is a toddler, cat or dog in the house. A trap can kill the intruder with a single snap: bait isn't essential, and cheese is by no means favourite. Mice are likely to go for bits of biscuits, cereals or chocolate. Poison can inflict a slow death, and leave a smelly corpse.

Your local council probably runs a pest-control service, and for a house, this may be free. Otherwise there are private firms dealing with mice, rats and other pests. Find them on line. Specialist advice on particular mouse problems can be had from DEFRA (Department for Environment, Food and Rural Affairs) in Bristol.

Once we get rid of the mice, how do we keep them away

Hygiene, for a start. Don't leave food (eg pet food) lying around, and keep everything in mouse-proof containers. Get rid of rubbish. Clean up areas where food scraps can build up ' for example, under work surfaces.

Outside the house, block any likely entrances ' for example, the space around a pipe. Don't forget how small the gap can be and still let that mouse through.

Why didn't our cat get the mouse

Good question. Wake him up and ask him.

• See also: DEFRA- Department for Environment, Food and Rural Affairs' advice - (PDF file)