DENVER-Lifeguards at indoor swimming pools with water spouts and sprays, waterfalls and water slides may contract a lung disease after breathing bacteria suspended in water droplets small enough to be inhaled into the lungs. This is the first time that indoor swimming pools have been identified as a source of continuously-occurring lung inflammation.
"Young, healthy, exercise-oriented lifeguards were sick," said Cecile Rose, M.D., of the Division of Environmental and Occupational Medicine at National Jewish Medical and Research Center. "If we hadn't figured this out, people would have developed more severe lung disease."
Sixty-five percent of a group of lifeguards at an indoor pool at a large municipal recreation center complained of symptoms such as frequent cough; recurrent wheezing or chest tightness; labored, difficult breathing; and/or fever that occurred during and after work hours, according to the study published in the American Journal of Public Health.
"At indoor swimming pools with spray water features, contaminated aerosols probably place workers at greater risk than users," she said, adding, "Regular users of indoor pools with water features may be at risk, too, if they spend a great deal of time in a contaminated environment."
Lifeguards with symptoms worked an average of 31 hours a week at the pool; only people working in the pool area suffered from the illness. Airborne bacteria--suspended in water droplets sprayed from various pool water features--made the lifeguards sick even though some initially blamed their symptoms on a cold or overwork.
Called granulomatous pneumonitis, this disease is characterized by inflamed nodules in the lungs. The disease is caused by the immune system in the lungs "turning on" in reaction to an inhalant.
"The water droplets were small enough to get deep inside the lung where they stimulated an immune reaction," she said.