How bad is it really to never deep clean a bathroom?

The public toilets are ridiculously dirty due to the high traffic. That’s why you’ll never touch a faucet or choose to push a door with your hip without a tissue.

You don’t have to worry about these pesky germs in your home, though, right?

Well, not so fast. Hate to tell you this, according to the University of Chicago, but research has found that private bathrooms contain the same potentially harmful pathogens as public restrooms, including staph, methicillin-resistant Staphylococcus aureus (MRSA), human papillomavirus (HPV) and herpes medicines.

If you haven’t cleaned your bathroom in a while, chances are it’ll be crawling with more of these creepy critters. So you may be wondering what this means for your health.

We spoke with Dr. Kelly Reynolds, director of the Center for Environmental, Exposure Science, and Risk Assessment at the University of Arizona, for 411s on whether a dirty bathroom can make you sick (and tips on how and how often you should clean your bathroom) .

A long list of live microbes can linger in an unclean toilet.

“Fungi, including mold, mildew, yeast and certain types of bacteria, can grow rapidly in bathroom environments,” says Reynolds. “These moisture-loving microbes can be seen in the nooks and crannies of showers, sinks, faucet handles and toilets, and they can even grow on floors and walls.”

Unsanitary bathroom space can make you sick, especially if you have a weakened immune system. Here are a few ways a graded restroom can wreak havoc on your health:

“Bacteria commonly found in showers can cause lung infections, especially in people who are already immunocompromised (for example, those with chronic infections, cancer, or autoimmune diseases),” Reynolds said.

In fact, according to the U.S. Centers for Disease Control and Prevention (CDC), shower heads and faucets can gather many disturbing microorganisms, including a harmful bacteria called Legionella pneumophila.

According to the CDC, when vulnerable people — such as the elderly, the immunocompromised, and those with chronic lung disease and other underlying health conditions — breathe or ingest water containing Legionella, they may Get a serious lung infection called Legionnaires’ disease.

Other pathogens in the bathroom can also cause respiratory problems. For example: mold. “Allergies to mold are common, and exposure to higher levels of mold can trigger allergic reactions or asthma,” Reynolds said.

A dirty bathroom can also ruin your skin’s health.

“A damp bathroom environment readily supports the growth of Trichophyton, the causative agent of athlete’s foot when sharing showers,” says Reynolds. Shared, we mean any shower used by anyone other than you (think: your partner, roommate, etc.)

Athlete’s foot is “an infection that causes dry, flaky and itchy skin on the feet that can spread to other parts of the body if left untreated,” she said.

But fungi aren’t your only enemy. In addition to athlete’s foot, you can get other common viral and bacterial skin infections, including warts, HPV, and MRSA, in a contaminated bathtub, according to the University of Utah Health Department.

According to the University of Utah School of Health, when you have open cuts or blisters on your feet and/or your immune system is weak, your risk of contracting one of these nasty skin pathogens increases.

If you have unexplained stomach problems, a dirty shower could be the source of your stomach problems.

Here’s why: “Ingesting bacteria that build up in the shower [such as E. coli] May also cause diarrhea or stomach flu symptoms [think: nausea and vomiting]’ said Reynolds.

Wait, how the hell did E. coli (often found in feces) get into your bathtub? Simple: If someone poops and doesn’t wash their hands, their dirty fingers can spread germs to everything they touch, including sinks, showers, and every surface in the bathroom.

The next person to use the bathroom is at risk of infection. When you touch a dirty shower surface, it’s easy to transfer harmful bacteria into your mouth, says Reynolds.

While most E. coli infections usually resolve without treatment in a week or so, sometimes vulnerable people such as children and the elderly can develop serious blood and kidney problems, according to the University of Michigan Health School.

There is no direct answer to this question. “It depends in part on how often it’s used, how well it’s ventilated and how dirty the surface is,” Reynolds said.

That said, “a good routine is to clean and disinfect bathroom surfaces at least weekly or more frequently, depending on usage and your susceptibility to infection,” she adds.

Here are Reynolds’ tips for keeping your bathroom microbe-free:

“Grout lines in showers, sinks, or walls and floors can be difficult to keep dry and microbe-free,” says Reynolds. But a little elbow grease can go a long way to eliminating bacteria hanging around the grout.

Every week, use a mild soapy cleanser and brush to remove any visible grubs, paying special attention to the grout.

Then use a disinfectant spray specifically designed to kill microbes, Reynolds said.

Sanitizing wipes are great for quickly disinfecting sinks, toilets and other handles, says Reynolds. Wiping down these areas weekly will keep bacteria and other bugs away.

For the interior of the toilet, a disinfectant spray and toilet brush (which can treat hard-to-reach surfaces, such as under the rim) will do the trick.

“Shower curtains tend to be the most likely place for microbes to accumulate in the bathroom,” says Reynolds. So keeping the curtains clean is key.

Washing your shower curtain once or twice a month (as long as it’s washer-safe) can help prevent it from becoming a hotspot for bacterial growth, Reynolds says.

If it’s not machine washable, spray it with a disinfectant (if you have a shower door, you can do that too), Reynolds says.

The same goes for bath mats, which can be a bastion of bacteria and other problematic pathogens. Wash (if possible) or use disinfectant spray to prevent microbial growth.

Remember, “any area that remains wet for extended periods of time [like bathmats] susceptible to contamination,” Reynolds said.

Shower heads can be a stronghold for bad biofilms, so they also need to be disinfected, Reynolds said. Add them to your list of weekly disinfected shower surfaces – a disinfectant spray or foam product will suffice.

Once a year for a deep clean, unscrew the shower head, soak it well in a diluted disinfectant solution, and wipe away stubborn dirt, debris, or biofilm (an old toothbrush is an excellent tool for this task).

The truth is, bathrooms can quickly build up microbes. “If you can see or smell mold or bacteria, you can probably grow millions of colonies,” Reynolds said.

That being said, as long as you have a strong immune system, a less shiny toilet probably won’t get in the way of your health.

For most people, a weekly wipe with a disinfectant will help control these lice.