I checked with Charles P. Gerba, PhD, a University of Arizona microbiologist and leading hygiene researcher—and found out that my haphazard approach isn’t so far off. “You certainly don’t have to sanitize the whole house to stay healthy. I would rather do other things besides clean,” he says. That’s my kind of germ expert! Gerba tells me that making just a few changes to my current cleaning routine—and focusing on the messiest areas—can go a long way toward keeping me and my family healthy. Here’s his take on fast cleaning tips—the least you should do to keep your house clean—or clean enough.

The Bedroom

The biggest chores in the bedroom—picking up laundry piles, vacuuming, dusting—are important in terms of aesthetics but not necessarily health. The exception: If you or a loved one is an asthmatic or suffers from allergies.  The least you should do: Dust and vacuum weekly if you have allergies or asthma; otherwise, let your personal “ick meter” be your guide. Try these allergy-friendly tools: Microfiber dusters grab and hold dust instead of spreading it around, and a powerful vacuum that carries the Green Label seal from the Carpet and Rug Institute will protect indoor air quality by sucking up soil.   To be even safer: 

Launder your pillows, quilts, and comforters every 2 to 3 months. Consider investing in a HEPA air purifier. It filters out small particles in the air and lessens the amount of allergy-aggravating dust circulating in the room.Steam clean your carpets every 12 to 18 months to knock out dust mites.[pagebreak]

The Kitchen

When Gerba and his colleagues ranked household areas by their germ load—including Streptococcus and diarrhea-inducing E. coli—the kitchen took the dubious top prize. “In most homes, you’re better off eating off the toilet than the kitchen counter,” Gerba says. That’s partly because “people tend to use antibacterial products in the bathroom but not in the kitchen,” he says. The least you should do: Clean your sponge. Those tiny crevices trap bacteria and “a sponge just wipes those germs all over the place,” Gerba says. Microwave your wet sponge or run it through the dishwasher daily. And for tasks that don’t require a sponge, like giving your countertops a once-over, opt instead for paper towels.  To be even safer:

Spritz the sink, counter-tops, and cutting boards with an antimicrobial spray after preparing every meal. Let the cleaner sit (check label for exact times) before wiping it up with a damp paper towel.Load the dishwasher or wash dishes each night. Wet, food-spattered surfaces are an ideal breeding ground for bugs.Swab the fridge handle and telephone with an antimicrobial cleaner daily to cut down on trading germs (if you open the fridge after you slice raw meat, the next person to touch the handle will encounter bacteria).Sweep up crumbs daily with a dry cloth sweeper and then toss the pad for a quick cleanup.

The Living Room

Feeling guilty you keep hiding the dust under the carpet? You’re on your honor when it comes to cleaning the living room—you can safely let the dirt pile up until it offends your sensibilities. The only items that need a little extra attention are the TV remote and the computer. They may look pristine, but since they’re constantly pawed, they’re almost certainly teeming with germs, according to Gerba. The least you should do: Clean the remote control, computer mouse, and keyboard with disinfectant wipes once a week and more often if a family member has a cold or flu. To be even safer: Dust and vacuum weekly if you have allergies or asthma. For germy carpet stains, keep an automatic spot cleaner, like the Bissell SpotBot Handsfree Compact Deep Cleaner ($130; Sears), on hand. Place it directly on the mess, turn it on, and let it do all the work. More from Prevention: 10 Decorating Tips For A Stress-Free Home

The Bathroom

Although the kitchen is the biggest germ pool in the house, the bathroom ranks second. According to Gerba’s research, the sink, faucet, and shower drain all can shelter bacteria that cause infections and diarrhea; cold viruses are also known to lurk in these areas. The least you should do: Wipe down the sink, faucet, shower drain, and toilet seat once a week with an antimicrobial cleaner. If a quick in-between cleanup is needed, it’s fine to use disposable sanitizing towelettes.  To be even safer:

Mop the floor (including behind the commode) every 2 weeks. Use an after-shower spray regularly to prevent mildew and grime buildup. After each shower or bath, lightly mist the whole area, including the inside of the curtain or shower door, with a spray like Tilex Fresh Shower Daily Shower Cleaner. No need to rinse or wipe it away. Drop a toilet tablet with bleach into the toilet tank every 3 months to effectively kill germs.Discard your plastic or vinyl shower-curtain liner every 6 months; after that it will take an enormous effort to keep it mold free. Or take a more Earth-friendly approach: Buy a nylon curtain liner and toss it in the wash every 3 to 4 months (make sure to check the label for washing instructions). 

Quick tip: Swap your washcloths for a synthetic pouf or sponge. They dry fast, so they don’t harbor germs. Just hang ’em and replace monthly. More from Prevention: The 11 Safest Non-Toxic Cleaners For Your Home