Waterborne Diseases Are Everywhere Now — Here's What to Know

Sipping a cold drink and taking a dip at the beach or pool is the ultimate way to cool off on a hot day. But it comes with a very real — and often unrealized — risk of developing waterborne diseases. This group of diseases can cause symptoms like diarrhea, nausea, vomiting, fever, and more. In some rare cases, these illnesses can be fatal.

Even though the US has one of the safest drinking water supplies in the world, about 7.2 million Americans get sick every year from diseases spread through water, according to the Centers for Disease Control and Prevention (CDC). But what exactly are waterborne diseases and how can you protect yourself and your family? Infectious disease experts break it down.

Waterborne diseases, aka water-related illnesses, are a group of diseases that are caused by ingesting, inhaling, or having direct contact with contaminants in water, according to the National Institute of Environmental Health Sciences (NIEHS). "'Waterborne diseases' is an umbrella term for these illnesses, which can range in severity," says Thomas Russo, M.D., professor and chief of infectious disease at the University at Buffalo in New York. Symptoms of waterborne illnesses include diarrhea, nausea, stomach cramps, vomiting, and fever, along with skin, ear, respiratory, and eye problems.

There is a wide range of waterborne diseases, but they're generally caused by bacteria, viruses, protozoa, and toxins that thrive in water, the CDC says. "The planet teems with microorganisms and water is no different," says infectious disease expert Amesh A. Adalja, M.D., a senior scholar at the Johns Hopkins Center for Health Security.

Climate change and global warming may play a role in the spread of some waterborne disease, Dr. Adalja says. "Some diseases may increase because of favored growth conditions, while others may decrease," he says. "Also, people's behavior could change and hotter weather could, for example, increase recreational water activities." Natural disasters like flooding, hurricanes, and tornadoes that disrupt sanitation systems "increase the risk of waterborne disease," he adds.

One particularly lethal pathogen, Naegleria fowleri (aka a brain-eating amoeba) "has been able to move further north because it's able to multiply in still-warm bodies of water impacted by climate change," Dr. Russo says.

There are actually quite a few. CDC data show that, in 2014 in the United States, 17 waterborne pathogens caused an estimated 7.15 million illnesses, 601,000 ER visits, 118,000 hospitalizations, and 6,300 deaths. The CDC also has a breakdown of the most common waterborne diseases, along with how many estimated cases they cause each year:

You can pick up waterborne diseases by coming into contact with contaminated water, this includes ingesting it, getting it up your nose, or breathing in aerosols, Dr. Russo says. To lower your risk of getting a waterborne disease, experts recommend taking these steps:

If you do contract a waterborne disease, most people tend to recover on their own. But treatment options depend on the type of disease. "Some are treated with supportive care, such as norovirus, while others may be treated with antibiotics, and others with antiparasitic agents," Dr. Adalja says. The American Family Physician journal recommends you talk to a doctor if "you have bloody diarrhea, diarrhea that lasts more than a week, or a cough with fever." Other serious symptoms, like a fever, stiff neck after swimming in a freshwater pond, or a bad skin infection with fever, are also red flags that you should see a physician.