Attention swimmers: More than half of the public pools tested in a new study contained bacterial evidence that someone may have pooped in the pool.
Investigators from the Centers for Disease Control and Prevention worked with state and local public health departments last summer to collect samples from pool filters at 161 pools in the metro-Atlanta area. Some of the pools were public, some were in private clubs and some were in water parks.
Over the winter, researchers used genetic tests to identify several types of pathogens in the filter samples. Among the 161 samples, 93 — or 58 percent — contained Escherichia coli, a bacterium that lives in the digestive tract of humans and other warm-blooded animals. The researchers treated the presence of E. coli as “a fecal indicator,” they wrote in their report.
How did it get into the pools? In all likelihood, swimmers delivered some of it into the water by failing to take a thorough, soapy shower before getting into the pool. “Each person has an average of 0.14 grams of fecal material on their perianal surface that could rinse into the water,” the report notes.
While E. coli was the most disgusting find, it wasn’t the most common. Investigators found Pseudomonas aeruginosa in 95 of the 161 filter samples, for a prevalence of 59 percent. The P. aeruginosa bacterium can cause swimmer’s ear, an inflammation of the outer ear and ear canal. It also causes itchy skin.
The results were published last week in the CDC’s Morbidity and Mortality Weekly Report.
The researchers emphasized that the results of their Atlanta-area survey can’t be generalized to the rest of the United States. But they noted that cases of recreational water illness have been on the rise from coast to coast, suggesting “that swimmers frequently introduce fecal material and pathogens into recreational water throughout the country.”