Swimming and Waterborne Diseases

Millions of people go swimming and wading each year, and most of them don't get sick. But the actual incidence of water borne disease is not known. Swimming is communal bathing. When you are in the water you are bathing with everyone else in the pool, waterpark, hot tub, spa, lake, river, or ocean. Germs in contaminated water can enter your system if you accidentally swallow the water, and can cause infection in your eyes, nose, ears, as well as in cuts and scrapes.

A pool usually becomes contaminated with germs after someone has a fecal "accident" in the pool. These accidents may be in the form of watery diarrhea. Therefore they are not as easily noticed as a formed stool. In addition, lakes, rivers, and the ocean can become contaminated by sewage, animal waste, and waste water runoff, especially after heavy rains.

What kinds of diseases can I catch from swimming?
A variety of diarrheal diseases and other infections such as skin, ear, and respiratory infections have been linked to swimming. However diarrhea is one of the most common illnesses associated with swimming. Diarrhea is spread when disease-causing germs from human or animal feces get into the water. You can get diarrhea by accidentally swallowing small amounts of water that contains these germs.

Can I get diarrhea from swimming in the ocean?
Yes. Diarrheal illness has been associated with swimming at marine beaches. Some common germs can live for long periods of time in salt water. Avoid swallowing the water.

Can I get sick from swimming in fresh water lakes and rivers?
Yes. Lakes and rivers can become contaminated by germs rinsed off the bottoms of swimmers, and from sewage, animal waste, and waste water runoff. Contact your state/local health department about germ testing results for local beaches. Do not swim in areas that have been identified by health departments as unsafe. Some germs that live in fresh water rarely infect humans. For example Naegleira is a germ that is found worldwide. Naegleria can be found in warm, stagnant bodies of fresh water and can cause severe disease. To prevent an infection by Naegleria, avoid swimming in small shallow ponds or areas posted "No Swimming." Do not swim in warm, stagnant, fresh water.

Doesn't the chlorine in the pool, hot tub, and spa kill all the germs?
No. Chlorine does a good job of killing most germs, but it does not sterilize the water. A few germs can survive normal pool, hot tub, and spa levels of chlorine for several hours to days. Chlorine must be maintained at proper levels to kill most germs. The high water temperature of hot tubs and spas may cause chlorine to evaporate faster. As a result, chlorine levels in hot tubs and spas need to be checked more regularly than in swimming pools. Remember: even if you can smell the chlorine odor the water is not germ free.

Skin infections are the most common infections spread through hot tubs and spas

Can I get diarrhea from playing and wading in ornamental water fountains?
Yes, if you swallow the water. Several diarrheal disease outbreaks have been associated with playing in ornamental water fountains. Not all ornamental water fountains are chlorinated and filtered. When people, especially diaper-aged children, play in or soak themselves with the water jets, they can contaminate the water.

What is my chance of getting diarrhea when I go swimming?
We don't really know. If public pools are properly maintained and chlorinated, the risk is thought to be low. However, over the past 10 years, over 150 outbreaks have been reported, involving small community pools, large waterparks, hot tubs, spas, lakes, and rivers.

Many outbreaks go unnoticed because people do not consider the pool water as a possible source of illness. It may take up to several weeks for some germs to cause symptoms of illness. The longer the time period between swimming and development of illness, the less likely people are to associate their illness with swimming activity. As a result, the number of actual outbreaks is probably greater than those currently reported.

Do swim diapers or swim pants prevent fecal matter from entering the water?
Using rubber pants, swim pants, or swim diapers has been suggested as a way to reduce fecal contamination of recreational water by infants and toddlers. These diapers may prevent formed stool from getting into the water, but they have not been tested to determine how well they contain stool after it becomes wet or how well they contain diarrhea. Swim diapers are most likely NOT able to prevent diarrhea (which may indicate ongoing illness) from leaking into the pool. Even though the diapers may reduce the release of formed stool, they are not leakproof. Change your child often and make frequent trips to the toilet.

What if I see fecal matter in the pool?
Immediately notify the pool attendant or lifeguard if you see fecal matter in the pool. He or she might ask swimmers to leave the water. Then the water may be tested and the chlorine levels raised, depending on the policy at the pool. Although this interruption can be frustrating, it is good public health practice, and may keep you and your family from getting sick.

Is the water safe if I don't see fecal matter in the pool?
Not necessarily. The absence of visible fecal matter in a pool does NOT mean that the pool water is safe. Diarrhea contamination of a pool will most likely be invisible. The safest, well managed pools are maintained with proper chlorine levels at ALL times. Chlorine will kill most, but not all germs, so informed and considerate swimmers play a crucial role in preventing waterborne diseases.

• DO NOT enter the water if you have diarrhea. People can spread germs in the water even without having an "accident."
• DO NOT swallow the water! Remember: it's everybody's bath water and chlorine does not kill all the germs.
• DO wash your hands and bottom thoroughly with soap and water after a bowel movement or changing diapers. Germs on hands end up everywhere, including the water.
• DO notify the lifeguard if you see fecal matter in the water or if you see persons changing diapers on tables and chairs.

PARENTS:

• DO take your child to the toilet for bathroom breaks often.
• DO change diapers in a bathroom, not near the pool or shore. Germs can contaminate surfaces and objects around the water.
• DO wash your child thoroughly, especially his or her bottom, with soap and water before swimming. Everyone has invisible amounts of fecal matter on his or her bottom that ends up in the water.
• DO NOT count on swim diapers or pants to keep fecal matter from leaking into the water. These products are not leakproof. Remember to take your child to the toilet often.
• DO keep an eye on your child at all times. Remember, kids can drown in silence.
• DO protect your child against sunburn by using a sunscreen with at least SPF 15 and both UVA and UVB protection, and be sure to re-apply it after swimming. Even a few serious sunburns can increase the risk of getting skin cancer.
• DO NOT allow your child to chew gum or eat while swimming or playing in the water. Chewing or eating while swimming could cause choking.

Each year, Medical College of Wisconsin physicians care for more than 180,000 patients, representing nearly 500,000 patient visits. Medical College physicians practice at Children's Hospital of Wisconsin, Froedtert Memorial Lutheran Hospital, the Milwaukee VA Medical Center, and many other hospitals and clinics in Milwaukee and southeastern Wisconsin.