Study shows those with weak immune systems should avoid the shower

May 3 2004

A study out of the San Diego State University Center for Microbial Sciences reveals that hundreds of millions of colorful bacteria thrive on shower curtains, waiting to attack those who think they are getting clean.

The bacteria hide in the scummy buildup at the bottom of shower curtains, according to the study by SDSU professor Scott Kelley and colleagues at two other universities that will be published in an upcoming issue of Applied and Environmental Microbiology.

"People with weak immune systems are especially susceptible to these opportunistic pathogens," Kelley said, adding that healthy adults are unlikely to face a serious threat from microorganisms found on shower curtains.

But for children, or patients with AIDS, or those undergoing chemotherapy or people with open wounds, some of the germs can be extremely dangerous.

"If these pathogens get into the body of someone who doesn't have a strong enough immune system, the symptoms can be serious," Kelley said. The bacteria can cause urinary tract infections, pneumonia, abscesses in the gut and more.

Kelley said the team of researchers was surprised to find such a large and diverse community of hundreds to thousands of potentially harmful organisms.

"We knew when we started to investigate the crusty buildup on shower curtains, we would find some scary stuff," Kelley said. "But we didn't think there would be so much."

A lot more study is needed to determine the source of the bacteria, which might be brought in through the water system, or through dirt that accumulates on peoples' bodies during the day. What role soap plays when it mixes with the bacteria and remains on a curtain also is unclear.

In the meantime, Kelly recommended that shower curtains be cleaned or replaced regularly.

"Or better yet, install glass shower doors, as these opportunistic pathogens don't seem to thrive on glass like they do on vinyl," he said.

The SDSU Center for Microbial Sciences provides a productive, interactive environment for developing new solutions for biodefense, antibiotic resistance, new infectious diseases, biotechnology applications and for training students to solve future problems in microbiology.

The center soon will be housed in the SDSU BioScience Center, a 38,000-square-foot laboratory and classroom facility scheduled to break ground this fall. The five-story building will house classes and research labs in many fields, including molecular biology, engineering, computational science, bioinformatics and business.

San Diego State University is the oldest and largest institution of higher education in the San Diego region. Founded in 1897, SDSU offers bachelor's degrees in 79 areas, master's degrees in 67 and doctorates in 14. SDSU's more than 33,000 students participate in academic curricula distinguished by direct contact with faculty and an increasing international emphasis that prepares them for a global future. For more information log on to www.sdsu.edu.