The Yuck Factor: CDC Says Pools Are Full Of Poop

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Finally, after a week of wool socks and extra blankets, today is feeling like a groovy summer day. But don't get too excited yet. With summer comes pools, and for many of us, public pools that are, according to a new report from the CDC, chock full of poop.


In the inimitably dry language of the nation's public health authorities: "A study of public pools done during last summer’s swim season found that feces are frequently introduced into pool water by swimmers."

Moreover, the study found:

"Fifty-eight percent of the pool filter samples tested were positive for E. coli, bacteria normally found in the human gut and feces. The E. coli is a marker for fecal contamination. Finding a high percentage of E. coli-positive filters indicates swimmers frequently contaminate pool water when they have a fecal incident in the water or when feces rinse off of their bodies because they do not shower thoroughly before getting into the water."

(Be honest, does anyone really shower before getting into the pool? Maybe it's time to start.)

So, what's a swimmer to do?

The CDC offers these tips:

--Keep feces and other contaminants out of the water.
--Do not swim when you have diarrhea.
--Shower with soap before you start swimming.
--Take a rinse shower before you get back into the water.
--Take bathroom breaks every 60 minutes.
--Wash your hands with soap after using the toilet or changing diapers.
--Check the chlorine level and pH before getting into the water.

Here's my desperate attempt at a silver lining: Germs are on the upswing (see, for instance, foodie Michael Pollan's take in this Sunday's New York Times) and a ton of new research finds that bacteria of all sorts can boost your immune system, and so fecal contamination may be just what the doctor ordered, right?

Here's more from the CDC news release:

Through the study, released today by the Centers for Disease Control and Prevention (CDC), researchers found germs in samples of pool filter water collected from public pools.
CDC collected samples of water from pool filters from public pools and tested the samples for genetic material (for example, DNA) of multiple microbes. The study found that 58 percent of the pool filter samples tested were positive for E. coli, bacteria normally found in the human gut and feces... No samples tested positive for E. coli O157:H7, a toxin-producing E. coli strain that causes illness.

Pseudomonas aeruginosa, which can cause skin rashes and ear infections, was detected in 59 percent of samples. Finding Pseudomonas aeruginosa in the water indicates natural environmental contamination or contamination introduced by swimmers. Cryptosporidium and Giardia, germs that are spread through feces and cause diarrhea, were found in less than 2 percent of samples.

The tests used in the study do not indicate whether the detected germs were alive or able to cause infections. Indoor and outdoor public pools were sampled.

The study did not address water parks, residential pools or other types of recreational water. The study does not allow CDC to make conclusions about all pools in the United States. However, it is unlikely that swimmer-introduced contamination, or swimmer hygiene practices, differ between pools in the study and those in the rest of the country.

“Swimming is an excellent way to get the physical activity needed to stay healthy,” said Michele Hlavsa, chief of CDC’s Healthy Swimming Program. “However, pool users should be aware of how to prevent infections while swimming. Remember, chlorine and other disinfectants don’t kill germs instantly. That’s why it’s important for swimmers to protect themselves by not swallowing the water they swim in and to protect others by keeping feces and germs out of the pool by taking a pre-swim shower and not swimming when ill with diarrhea.”

In addition to the precautions listed above, the CDC offers this guidance to the parents of young children:

--Take children on bathroom breaks every 60 minutes or check diapers every 30–60 minutes.
--Change diapers in the bathroom or diaper-changing area and not at poolside where germs can rinse into the water.

This program aired on May 16, 2013. The audio for this program is not available.

Rachel Zimmerman Twitter Health Reporter
Rachel Zimmerman previously reported on health and the intersection of health and business for Bostonomix.