AIDS Patients Vulnerable to Water Bacteria

The source of one of the most common infections in people with advanced AIDS may be tap water, a Dartmouth College researcher says.

About 40% of AIDS patients develop a serious infection called mycobacterium avium complex, or MAC, according to Dr. C. Fordham von Reyn, associate professor of medicine and director of the infectious disease section at Dartmouth-Hitchcock Medical Center. The infection causes severe illness and weight loss, shortening the lives of AIDS patients by about seven months, he said.

Von Reyn and other researchers found that some institutional water systems, including the hospitals in which infected patients were treated, contained the same bacterial strains as AIDS patients in the study.

Using data from 36 AIDS patients living in New Hampshire and Boston, researchers were able to isolate the source using a DNA fingerprinting technique called pulsed field gel electrophoresis. The technique was adapted for use on MAC by Dr. Robert Arbeit of Boston University School of Medicine.

Researchers took water samples from each person’s home and from hospitals where patients were treated, and tested the samples to determine the source of the bacterium. Results of the study pointed to hot water systems in the hospitals as the common denominator among 14% of the AIDS patients.

The means of transmission is unknown, but researchers believe that hospitalized AIDS patients could have come into contact with the waterborne bacterium through exposure to hot shower water, through the use of bronchoscopes (devices used to view airways and lungs) that may have been rinsed in warm water, or by drinking tap water.