When you look at health news right now, it feels like every other headline is either a warning about the next rare disease or a tale about how flourishing gut bacteria is the secret to happiness. So should we all embrace the world’s dirt, walking around barefoot in the mud, or live in spacesuits with a bottle of bleach at the ready? The very fact that we still use the word germs to describe bacteria, viruses, parasites, and whatever just attached itself to your shoe in the airport bathroom is probably one source of our collective confusion. We went in search of the answers to these seemingly conflicting reports about pathogens.

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Our Constantly Evolving Immune System

In utero, babies have rather weak, incomplete immune systems. This is probably so they can peacefully coexist with their mothers’ bodies but also because in the womb, they have little exposure to bacteria.The good gut microbiota—a.k.a. the reason everyone pretends to like kombucha—first comes from the birth canal and then everything babies are exposed to afterward. Their memory T-cells (the white blood cells that kill antigens) are also a blank slate until they’ve had something to fight and “learn” from.

“From the moment babies are born, they interact with the environment and come into contact with all kinds of germs,” says William Shaffner, M.D., an infectious disease specialist at the Vanderbilt University Medical Center in Nashville. “We live in a very germy world. This interaction with the germy world actually results in protection of children against all kinds of infections.”

There’s also evidence that exposure to microbes prevents children from developing allergies. You may have heard of the study in Sweden that indicates kids whose parents immediately sanitized dropped pacifiers were more likely to have asthma, eczema, and allergies than the children whose parents licked the pacifiers clean. (We’re just going to assume the parents who sucked on that dirt are doing well too.)

OK, but Not All Germs Are Created Equal

A few unsettling facts: While some bacteria are part of our immune system, there are, of course, plenty of others that are deadly—and becoming deadlier as they grow resistant to antibiotics. According to the Review on Antimicrobial Resistance (commissioned by the U.K. Department of Health), at least 700,000 people across the world die each year of bacterial infections, malaria, tuberculosis, and HIV/AIDS as a direct result of drug-resistant bacteria. The WHO says that 480,000 people in the world develop drug-resistant TB each year.

While not usually fatal, the norovirus (that nasty bug we usually call the stomach flu) is so highly contagious, it takes just 18 viral particles to make one person ill, and the virus lives on in an infected person’s stool for two weeks. Herpes simplex type-1 (oral herpes) can be passed to a child simply by pinching her cheek. Also, 20 percent of sexually active adults have herpes simplex type-2.

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In July, a 3-week-old baby made headlines when she tragically died from complications of viral meningitis after contracting herpes, probably from someone who kissed her when she was a week old at her parents’ wedding.

“What I will say about viral meningitis in infants is that this issue is now super, super rare,” Shaffner says. “A much more common cause of serious disease in children that can actually kill them is influenza.”

In the United States, influenza and pneumonia are one of the leading causes of death (ranking eighth overall in 2014).

“The recommendation is to give every child an influenza vaccine,” Shaffner says. “It will provide—if not complete—certainly partial protection. Also, moms and dads should be comforted that the lights are on in the research laboratories at night. People keep working to develop a better flu vaccine and other mechanisms of protection for our children.” In case you’ve forgotten, vaccines are good for us all.

Go Ahead: Touch Those Toilet Seats, Doorknobs, and Keyboards

“You don’t have to spray every computer keyboard with disinfectant, which will ruin it anyway,” Shaffner says. “And you don’t have to worry about picking up a phone or a dollar bill. You’re not going to get killed from that. A few years ago, one of the most common questions I got was, ‘What can you pick up from a public toilet seat?’ The answer is nothing. That’s not a risk. If it were, we wouldn’t have public toilets.”

Even though places like public restrooms are basically petri dishes for bacteria and viruses, in most cases, all you have to do is wash your hands to be rid of them.

On Handwashing and Hand Sanitizer

Though they seem ridiculously obvious, think twice the next time you want to laugh at the handwashing instructions you see at restaurants and medical offices. They save lives. The official recommendation from the CDC is to wet your hands first; lather them up with regular (nonantibacterial) soap, being sure to get under fingernails and between fingers, for the time it takes to sing “Happy Birthday” twice; rinse; and dry.

The FDA denounced antibacterial soap as useless at best and, at worst, potentially responsible for making bacteria more drug resistant. Hand sanitizer, however, is still your second-best friend after soap and water. It doesn’t get rid of dirt or kill all germs—norovirus, for example, may stick around—but it’s better than nothing when you aren’t near a sink.

“My wife always has a small bottle of hand hygiene liquid in her purse; I have one in the glove compartment of my car,” Shaffner says. “And then my wife has a simple rule in our house: You walk in the front door, hang up your coat and then go directly to the sink and wash your hands. Simple rules like that really are the great protection.”

So unzip your bubble and the next time you read scary health news, just remember the lyrics to “Happy Birthday.”

Sabrina Rojas Weiss lives in Brooklyn, surrounded by her fellow freelance writers and competitive stroller-pushers. Her work has appeared on Refinery29, Yahoo, MTV News, and Glamour.com. Follow her on Twitter @shalapitcher.