KEY POINTS

• Germs in recreational water can cause illnesses.
• Recreational water is water where people swim, play, or relax -- like pools, hot tubs, splash pads, oceans, lakes, and rivers.
• Take steps every time you swim to prevent these illnesses.

Overview

The most common swimming-related illnesses are diarrhea, skin rashes, swimmer's ear, pneumonia or flu-like illness, and irritation of the eyes or respiratory tract.

You can get swimming-related illnesses if you swallow, have contact with, or breathe in mists of water contaminated with germs. You can also get swimming-related illnesses by having contact with chemicals that are in the water or inhaling chemicals that evaporate from the water and turn into gas in the air.

Outbreaks of diarrhea are the most common swimming-related illness outbreaks. People who are sick with diarrhea can spread diarrhea-causing germs to others if they have diarrhea in the water. If others swallow the contaminated water, they can become infected. Chemicals (chlorine or bromine) inactivate or kill most germs in properly treated water within minutes; Crypto (short for Cryptosporidium) can survive for more than 7 days.

Risk factors

Children, pregnant people, and people with weakened immune systems are most at risk for swimming-related illnesses.

Recreational water might be contaminated with Crypto, which can cause life-threatening symptoms in people with weakened immune systems. These individuals should consult their healthcare provider before participating in recreational water activities, such as swimming.

How to prevent swimming-related illnesses

Pools, hot tubs, and water playgrounds with proper chlorine or bromine levels and pH are less likely to spread germs. Injuries and drownings are less likely when trained staff and adequate safety equipment are present.

Before you get in

• Check latest inspection results on the state or local health department website or on-site.
• Make sure the drain at the bottom of the deep end is visible. Check that the drain covers appear to be secured and in good condition.
• Check for lifeguard(s):
  • If on duty, the lifeguard(s) should be focused on swimmers and not distracted.
  • If no lifeguard is on duty, find the location of the safety equipment, such as a rescue ring or pole.
• Make sure no chemicals are out in the open.

Check yourself

• Stay out of the water if you are sick with diarrhea. If you have been diagnosed with Crypto, don't go back in the water until two weeks after diarrhea has completely stopped.
• Stay out of the water if you have an open cut or wound (particularly from a surgery or piercing). If you do go in the water, use waterproof bandages to completely cover the cut or wound.
• Shower before you get in the water. Rinsing off in the shower for just one minute removes most of the dirt or anything else on your body that uses up chlorine or bromine needed to kill or inactivate germs.

Once you are in

• Don't pee or poop in the water.
• Don't swallow the water.
• Use well-fitting, Coast Guard-approved life jackets, not air-filled toys (for example, water wings), for flotation assistance.
• Keep an eye on children at all times. Kids can drown in seconds and in silence.
• Take kids on bathroom breaks and check diapers every hour.
  • Change diapers away from the water to keep germs from getting in.
• Dry ears thoroughly after swimming.

If you are at an ocean, lake, or river:

• Check for beach or lake closure information on your state or local government website or signs on-site.
• Cloudy water can be a warning that there are more germs in the water than normal.
• Stay out if you see any pipes draining into or around the water.
• Wash your hands for 20 seconds before eating food, especially if you have been playing in or touching sand. If soap and water are not available, use an alcohol-based hand sanitizer that contains at least 60% alcohol. Hand sanitizer might not be as effective when hands are visibly dirty or greasy, so wiping sand off before using it might be helpful.

KEY POINTS

• Diarrhea is the most common illness reported in outbreaks linked to water in pools, hot tubs, splash pads, oceans, lakes, or rivers.
• You can get sick with diarrhea if you swallow contaminated water in these recreational water places.

Overview

When you go in a swimming pool, hot tub, splash pad or other recreational water venue, you can swallow germs that cause diarrhea like Crypto, Giardia, Shigella, Norovirus, and E. coli O157. These germs can survive in properly chlorinated water for minutes to days, depending on the germ.

Exposure

If someone is sick with diarrhea and has an accident in the water, millions of diarrhea-causing germs can get in the water. If another person swallows even a small amount of that contaminated water, they can get sick. Germs can also get in the water from small amounts of poop rinsing off swimmers’ bodies.

Filters and disinfectants (chemicals like chlorine or bromine) work together to help kill germs. Filters remove debris (such as leaves), which can use up the disinfectant in the water that is needed to kill germs.

Pool staff make sure chlorine or bromine is at the level needed to kill most germs in the water within minutes. However, you can still be exposed during the time it takes for the disinfectant to come in contact with the germs and kill them. You can also get diarrhea from germs that are hard to kill, such as Crypto. Crypto can stay alive for more than 7 days, even if the water is properly disinfected.

Facilities with multiple pools often use one filtration system for all of the pools. This causes water from multiple pools to mix and means that germs from one person's body could contaminate the water in more than one pool.

Prevention steps and strategies

We all share the water we swim, play, or relax in. Each of us can help protect ourselves, our families, and our friends from germs that cause diarrhea.

Take the following steps when swimming or playing in the water:

• Stay out of the water if you are sick with diarrhea.
  • If you have Crypto, don't go back in the water until 2 weeks after your diarrhea has completely stopped.
• Don't poop in the water.
• Don't swallow the water.
• Take kids on bathroom breaks and check diapers every hour.
  • Change diapers away from the water to help keep germs out of the water; wash your hands after.

Before going in pools, splash pads, and hot tubs, rinse off! A one-minute shower will remove most of the dirt, sweat, and oils on your body that use up the pool chemicals needed to kill germs.

KEY POINTS

• If contaminated water stays on someone's skin for a long time, it can cause a rash known as "hot tub rash" (Pseudomonas folliculitis).
• Hot tub rash is caused by the germ Pseudomonas aeruginosa, which is commonly found in the environment (for example, in water or soil).

Symptoms of hot tub rash

Hot tub rash usually appears a few days after sitting in a poorly maintained hot tub.

Hot tub rash can affect people of all ages. It is often worse in areas where a swimsuit held contaminated water up against the skin. Symptoms include:

• Itchy, red, and bumpy rash

• Pus-filled blisters around hair follicles

Mild rashes usually clear up in a few days without medical treatment. Check with your healthcare provider if a rash gets worse or if you get it more than once.

Prevention steps and strategies

To reduce the risk of hot tub rash

• Remove your swimsuit and shower with soap after getting out of the water, especially hot tubs.
• Wash your swimsuit after using it.
• Use test strips to check the water, especially in hot tubs, for adequate disinfectant level and pH. CDC recommends the following disinfectant and pH levels for hot tubs:
  • Chlorine: 3–10 parts per million (ppm or mg/L) or bromine 4–8 ppm
  • pH: 7.0–7.8

If chlorine level, bromine level, or pH is not within the correct range, tell the operator or owner immediately.

KEY POINTS

• People are at risk for respiratory infections if they breathe in mist from a hot tub that contains Legionella bacteria.
• Legionnaires' disease and Pontiac fever are illnesses caused by Legionella.
• There are steps you can take to protect yourself from Legionella when using a hot tub.

Overview

Properly maintaining hot tubs with the correct disinfectant (like chlorine) and pH levels reduces the risk of germs, like Legionella, from spreading.

When to see your healthcare provider‎

Exposure

Legionella bacteria can cause a life-threatening type of pneumonia called Legionnaires' disease. Legionella can also cause Pontiac fever, a milder illness without pneumonia. People can get Legionnaires' disease or Pontiac fever from hot tubs when they breathe in mist that contains Legionella.

People can be exposed to Legionella in hot tubs when these bacteria get into water systems and grow (increase in numbers)

Risk factors

Certain groups of people are more likely to get Legionnaires' disease, including:

• People 50 years of age or older
• Current or former smokers
• People with chronic lung disease, weakened immune systems, or those who take medicines that lower their body's ability to fight germs and sickness.

Prevention steps and strategies

Below are steps you can take to test hot tub water and find out if the hot tub is being properly operated.

• Buy test strips at your local retailer or pool supply store. Be sure to check the expiration date.
• Use the test strips to check these levels:
  • Free chlorine level should be 3–10 parts per million
  • Bromine level should be 4–8 parts per million
  • pH should be 7.0–7.8
• Tell the hot tub operator or owner if you find improper chlorine or bromine levels or pH.

Questions to ask your hot tub operator

• What was the most recent health inspection score for the hot tub?
• Are the disinfectant levels and pH checked at least twice per day?
• Are the disinfectant levels and pH checked more often when the hot tub is being used by a lot of people?
• Are the following maintenance activities performed?
  • Daily removal of the slime or biofilm layer by scrubbing and cleaning
  • Replacement of the hot tub water filter according to the manufacturer's recommendations
  • Replacement of hot tub water as often as required by the health department or recommended by the manufacturer

KEY POINTS

• Head lice, MRSA (methicillin-resistant Staphylococcus aureus), and pinworm infection are unlikely to be spread through recreational water, like pools, hot tubs, or splash pads.
• These infections, however, can be spread by contact with people or objects when visiting these recreational water venues.
• Learn how to protect yourself.

Exposure

Head lice

Head lice are unlikely to be spread through pool, hot tub, or splash pad water.

Head lice mainly spread by direct, head-to-head with the hair of a person infested with lice. Head lice move by crawling; they cannot hop or fly. Head lice survive by holding on tightly to hair, so are unlikely to come off a person's head in the water. Head lice can also be spread by sharing towels, brushes, or other items that have been in contact with an infected person’s hair.

Chlorine levels used at pools, hot tubs, or splash pads do not kill head lice.

MRSA

There have been no reports of MRSA spreading through recreational water. MRSA does not survive long in water that has proper disinfectant (chlorine) and pH levels.

There is a potential risk of MRSA spreading through direct contact with another person's MRSA infection or direct contact with contaminated objects and surfaces. Direct contact can happen when you touch another person’s MRSA infection. Indirect contact can happen when you share items (like towels or razors) or touch surfaces (like handrails or locker room benches) contaminated with MRSA. MRSA is most likely to cause infection when the germ comes into contact with an uncovered cut or scrape.

Pinworm infection

Pinworm infections are rarely spread through recreational water. Pinworm infections occur when a person swallows pinworm eggs picked up from contaminated surfaces or feces (poop). Although chlorine levels found in pools are not high enough to kill pinworm eggs, the presence of a small number of pinworm eggs in thousands of gallons of pool water makes the chance of infection unlikely.

Prevention steps and strategies

Head lice

To protect yourself from head lice at the pool, do not share towels, brushes, or other items that come into contact with someone else's hair. If you already have lice, do not swim or wash your hair within 1–2 days of treating it with anti-lice shampoo—these actions will make the treatment less effective.

MRSA

All swimmers

• Don't touch any bumps, cuts, infected areas, or bandages on another person's skin.
• Don't share items, like towels or razors, with other people.
• Keep cuts and scrapes clean and cover them with bandages.
• Talk to pool, hot tub, and splash pad operator to make sure they:
  • Clean frequently touched surfaces
  • Wash towels after each use
  • Maintain proper disinfectant level and pH in the water to kill germs

If you have a skin infection

• It might be difficult to keep infected skin completely covered with watertight bandage while in the water, so it is best to stay out of the water. If you do go in the water, completely cover any bumps, cuts, or infected areas with watertight bandages.
• Practice good hygiene by regularly washing hands with soap and water.
• Don't let other people touch your bumps, cuts, infected areas, or bandages.

Pinworm infection

Washing your hands with soap and warm water after using the toilet, changing diapers, and before handling food is the best way to prevent pinworm infection at recreational water venues.

KEY POINTS

• Chlorine is used in pools to kill germs, but it can also combine with sweat, dirt, and pee to create chemical irritants called chloramines.
• Chloramines can turn into gas and irritate the eyes and lungs.
• Keeping sweat, dirt, and pee out of the water helps prevent chloramines from forming.

Overview

Chlorine is commonly added to the water to prevent the spread of germs and outbreaks in swimming pools and other recreational water venues. When chlorine combines with pee, poop, sweat, dirt, skin cells, deodorant, and makeup that wash off swimmers' bodies, it causes two problems:

• It decreases the amount of chlorine available to kill germs.
• It creates chemical irritants called chloramines ("chlor," short for chlorine, and "amines," compounds that contain nitrogen).

Exposure

If you smell "chlorine" at the place you swim, you are probably smelling chloramines. Chloramines in the water can turn into gas in the surrounding air. This is more common in indoor pools, which often are not as well-ventilated as outdoor pools. The chloramines that form in pool water are different from the chloramine that is sometimes used to treat drinking water.

Signs and symptoms

Breathing in or coming into contact with chloramines at the places we swim can lead to negative health effects.

• Anyone in the swimming area, swimmers or otherwise, can experience respiratory symptoms such as nasal irritation, coughing, and wheezing. Asthma attacks can be triggered in people who have asthma.
• Swimmers can experience red and itchy eyes, skin irritation, and rashes.

Prevention tips

Prevent chloramines from forming

• Never swim or let your kids swim if sick with diarrhea.
• Use the toilet before getting into the water.
• Shower before getting into the water. Rinsing off in the shower for just one minute can remove most of the dirt or anything else on your body.
• Wear a bathing cap while in the water.
• Never pee in the water.
• Every hour:
  • Take kids on bathroom breaks.
  • Change diapers away from the poolside.

Talk to others

• Tell other swimmers and parents of young swimmers about chloramines and the steps they can take to help prevent them.
• Encourage pool operators to take steps known to prevent and get rid of chloramines.
• Tell the lifeguard or pool operator immediately if you or your family or friends:
  • See poop in water;
  • Smell chemical odors in the swimming area; or
  • Experience respiratory, eye, or skin irritation that could be linked to the water or the air surrounding the water.

KEY POINTS

• Swimmer’s ear is a bacterial infection caused by water that stays in the outer ear canal for a long period of time, providing a moist environment for bacteria to multiply.
• Children are more likely to get swimmer's ear than adults, but it can affect anyone.
• Swimmer’s ear is not contagious.

Overview

Swimmer's ear (also known as acute otitis externa) is a bacterial infection. It is typically caused by water that has stayed in the outer ear canal for a long time. This wears down protective wax and skin and provides a moist environment for bacteria to multiply.

Anyone can get swimmer's ear, but it is most often seen in children. Swimmer's ear cannot be spread from one person to another.

Swimmer's ear is different from a middle ear infection, which is also common in children.

Signs and symptoms of swimmer's ear

• Pain when the outer ear is tugged or when pressure is put on the part of the outer ear that sticks out in front of the ear canal (tragus)
• Itchiness inside the ear
• Drainage from the ear
• Redness and swelling in the ear

Prevention steps and strategies

Keep ears as dry as possible

• Use a bathing cap, ear plugs, or custom-fitted swim molds when swimming.

Dry ears thoroughly after swimming or showering

• Tilt head back and forth so that each ear faces down to allow water to drain out of the ear canal.
• Use a towel to dry ears well.
• Pull earlobe in different directions when ear faces down to help water drain out.
• If water remains, you can use a hair dryer on the lowest heat and speed/fan setting. Hold the hair dryer several inches from ear.

Check with your healthcare provider about using ear-drying drops after swimming

• Don't use these drops if you have ear tubes (tympanostomy tubes), punctured ear drums, swimmer's ear, or ear drainage.

Don't put objects in ear canal

• Including cotton-tip swabs, pencils, paperclips, or keys.

Don't try to remove ear wax

• Ear wax helps protect the ear canal from infection.

Treatment

• Check with your healthcare provider if you have ear pain or drainage from the ear.
• Swimmer's ear can be treated with antibiotic ear drops

KEY POINTS

• Swimmer's itch is an infection caused by a parasite.
• It can cause an allergic reaction and rash on your skin.
• Swimmer's itch is not contagious and does not spread from person to person.

Overview

Swimmer’s itch, also called cercarial dermatitis, appears as a skin rash caused by an allergic reaction to certain microscopic parasites that infect some birds and mammals. These parasites are released from infected snails into fresh and salt water (such as lakes, ponds, and oceans). While the parasite’s preferred host is the specific bird or mammal, if the parasite comes into contact with a swimmer, it burrows into the skin causing an allergic reaction and rash. Swimmer’s itch is found throughout the world and is more frequent during summer months.

Symptoms

Symptoms can include

• tingling, burning, or itching of the skin
• small reddish pimples
• small blisters

Within minutes to days after swimming in contaminated water, you may experience tingling, burning, or itching of the skin. Small reddish pimples appear within twelve hours. Pimples may develop into small blisters. Scratching the areas may result in secondary bacterial infections. Itching may last up to a week or more but will gradually go away.

Because swimmer’s itch is caused by an allergic reaction to infection, the more often you swim or wade in contaminated water, the more likely you are to develop more serious symptoms. The greater the number of exposures to contaminated water, the more intense and immediate symptoms of swimmer’s itch will be.

Be aware that swimmer's itch is not the only rash that may occur after swimming in fresh or salt water.

Exposure risks

Anyone who swims or wades in infested water may be at risk. Larvae are more likely to be present in shallow water by the shoreline. Children are most often affected because they tend to swim, wade, and play in the shallow water more than adults. Also, they are less likely to towel dry themselves when leaving the water.

Water safety after outbreaks

Many factors must be present for swimmer’s itch to become a problem in water. Since these factors change (sometimes within a swim season), swimmer’s itch will not always be a problem. However, there is no way to know how long water may be unsafe. Larvae generally survive for 24 hours once they are released from the snail. However, an infected snail will continue to produce cercariae throughout the remainder of its life. For future snails to become infected, migratory birds or mammals in the area must also be infected so the lifecycle can continue.

Swimming pools

As long as your swimming pool is well maintained and chlorinated, there is no risk of swimmer’s itch. The appropriate snails must be present in order for swimmer’s itch to occur.

How it spreads

The adult parasite lives in the blood of infected animals such as ducks, geese, gulls, swans, and certain mammals such as muskrats and raccoons. The parasites produce eggs that are passed in the feces of infected birds or mammals.

If the eggs land in or are washed into the water, the eggs hatch, releasing small, free-swimming microscopic larvae. These larvae swim in the water in search of a certain species of aquatic snail.

If the larvae find one of these snails, they infect the snail, multiply and undergo further development. Infected snails release a different type of microscopic larvae (or cercariae, hence the name cercarial dermatitis) into the water. This larval form then swims about searching for a suitable host (bird, muskrat) to continue the lifecycle. Although humans are not suitable hosts, the microscopic larvae burrow into the swimmer’s skin, and may cause an allergic reaction and rash. Because these larvae cannot develop inside a human, they soon die.

Reducing risk

To reduce the likelihood of developing swimmer’s itch

• Do not swim in areas where swimmer's itch is a known problem or where signs have been posted warning of unsafe water.
• Do not swim near or wade in marshy areas where snails are commonly found.
• Towel dry or shower immediately after leaving the water.
• Do not attract birds (e.g., by feeding them) to areas where people are swimming.
• Encourage health officials to post signs on shorelines where swimmer's itch is a current problem.

When the weather gets warm, you may want to get outside for some fun in the sun. Going to a pool, lake, or beach often tops that list. Spending time in the water can bring health hazards. But some simple habits can help keep your summer fun—and healthy.

Many different germs and organisms can live in water. These include bacteria, viruses, parasites, and plant matter that can make you sick.

A lot of germs that live in water cause stomach and intestinal upset. These can bring diarrhea or vomiting. You can also get skin rashes, ear or eye pain, and a cough or congestion after swimming in contaminated waters.

Common culprits for gut symptoms after swimming are parasites. These include Cryptosporidium (Crypto) and Giardia intestinalis. But bacteria, like E. coli, and viruses can also be the cause.

Many water-borne germs come from the poop of people and animals. So it’s important to never go to the bathroom or to change dirty diapers near the water. If you bring a pet, be sure to pick up after them.

Pools are often treated with a chemical called chlorine to kill germs. But it doesn’t work on all of them immediately. Some, like Crypto, can linger for days despite the chlorine. And natural bodies of waters, like oceans and lakes, can’t be treated with chemicals.

“You can’t just look at the water and say, ‘I think that there’s an elevated level of bacteria,” says Dr. Dwayne Porter at the University of South Carolina. But scientists can test recreational waters for certain bacteria.

Porter’s group studies ways to monitor water conditions around the local beaches. They collect data about a bacteria called enterococcus. Enterococcus lives in the guts of people and animals. High levels of the bacteria can mean the water is contaminated with poop. That often means that other germs are present, too.

His group works with local partners to create daily water forecasts. The forecasts predict which areas may have high levels of bacteria. They alert local residents using the websites howsthebeach.org and howsmyscriver.org.

Porter and his colleagues plan to expand the alert system to include Vibrio vulnificus (Vibrio). Vibrio can make you very ill if you eat contaminated seafood. They are also flesh-eating bacteria. If they infect a wound on your skin and aren’t treated, it can lead to amputation or death.

The team is trying to figure out what factors can predict an increased risk of Vibrio infections. Changes to the water’s temperature and salt levels may increase the bacteria’s growth. Another possibility is toxic algae blooms. These release nutrients that help the bacteria thrive.

Certain types of algae also release toxins that contaminate the water and the air. So, in general, it’s important to avoid areas with toxic algae and not eat the seafood found there.

Being aware of local water conditions before you go to the beach can help you stay safe. “If there are concerns with either the bacteria or other hazards, focus on other activities to do,” Porter advises.

For more tips on staying safe in the water, see the Wise Choices box.

Stay Healthy in the Water

• Shower before and after swimming.
• Try not to swallow the water.
• Never go to the bathroom in the water. Take kids for bathroom breaks and check diapers every hour. Change diapers away from the water.
• Stay out of the water if you’ve had diarrhea recently to help protect others from infectious germs.
• Always wash your hands before you eat or drink after playing in recreational waters or in the sand.
• Cover open wounds with waterproof bandages.
• Don’t swim in water that looks murky or has an odor.
• Stay out of the ocean for at least 24 hours after a storm. Avoid places where storm water is released on the beach.
• Check for warning signs posted around the area. Ask lifeguards about the water conditions.
• Check local alert systems. Visit the EPA's website for information on specific U.S. beaches.