Common mistakes make your house dusty

Wearing Your Shoes in the House

Making a point to take off your shoes in the mud room or right near the entrance of your home could prevent you from tracking a lot of nastiness inside. Researchers from the University of Arizona collected germs and microbes on footwear and found 421,000 units of bacteria on the outside of the shoe, including E. coli, meningitis and diarrheal disease; Klebsiella pneumonia, a common source for wound and bloodstream infections as well as pneumonia; and Serratia ficaria, a rare cause of infections in the respiratory tract and wounds. Gross doesn't even begin to cover that.

Not Cleaning Your Welcome Mat

You may have heard it before, but hear it again: The welcome mat may "live" outside the house, but it's one of the germiest zones you encounter! Consider what was found on the bottom of those shoes? Obviously, the welcome mat at your doorstep is a hotbed of all of that bacteria. So it definitely pays to disinfect it about once a week.

Not Utilizing Fresh Air

Opening your windows on occasion may do more than simply allow fresh spring air in. Relying on outside air can actually maximize natural ventilation and reduce the risk of airborne infections, suggests a study by researchers at Imperial College London in the UK.

Placing Your Purse on a Kitchen Countertop

Your purse goes with you everywhere, so it makes sense that sometimes it ends up on your kitchen countertop. But this is one swift way to spread lots of icky germs. Charles Gerba, a professor of environmental microbiology at the University of Arizona, studied purse bottoms and found there were up to 10,000 bacteria per square inch there -- and a third of the bags tested positive for fecal bacteria. Clearly, you do not want to place that germ bomb just anywhere ... especially where you prepare food!

Letting Hot Food Cool in the Fridge

When cleaning up the kitchen after dinner, it's tempting to take a hot casserole, for instance, throw some tin foil over it, and put it in the fridge. But this is a quick way to create bacteria, because it makes for uneven cooling, during which bacteria can multiply and increase the risk of foodborne illness, notes the USDA. Better to divide your leftovers up into smaller containers so they can cool more quickly -- and safely.

Not Disinfecting Your Remote Control

Gerba and his team at the University of Arizona have also looked at television remote controls and deemed them frighteningly germ-packed. Some even turned up with MRSA. In a separate study, done by researchers at the University of Virginia detected cold viruses on the majority of remotes they tested. Certainly a case for a once weekly swipe of a disinfecting wipe on your "clicker."

Leaving the Toilet Seat Open

Research from Leeds University showed that the germ C. difficile can be pushed up to 10 inches above toilet seats every time you flush with the lid open. The highest levels of bacteria were found right after a flush, and even 90 minutes later. Hence why it may be best to close your toilet seat when you flush!

Letting Towels Dry on Hooks

You may have always hung your towels up on hooks in your bathroom, but this is the fast-track to allowing the moisture that's trapped between the folds to trigger mildew and bacteria growth. What's more, they can pick up germs from hands and toilet droplets. Better to spread them out on a towel bar -- and wash them at least weekly!

Bringing Your Cell Phone Into the Bathroom

You know it's kinda nasty, but you probably do it anyway. Well, stop, because 1 in 6 cell phones are covered with E. coli, that potentially illness-causing bacteria that is fecal in origin, according to researchers from the London School of Hygiene & Tropical Medicine and Queen Mary, University of London.

Not Washing Your Reusable Grocery Bags

Using cloth bags to tote your groceries to and from the store is an eco-friendly but possibly also germy practice. Gerba is the co-author of a study that found coliform bacteria including E. coli in half of the bags he and his team sampled. The solution that's good for the environment and your home's cleanliness: laundering them on a weekly basis.