Beware of MAC Lung Infections Lurking in Showerheads

Mycobacterium avium Complex (MAC) is a cousin to the tuberculosis germ but is not contagious. The MAC microbes live in our environment -- in the soil, air and water. Recently this bacterium has been found in showerheads and is disbursed in the fine mist of water droplets that we inhale during showering. For most healthy people this mycobacterium doesn't affect the body, however in people with immune-compromising conditions the risk of infection is possible.

What is MAC?

MAC is responsible for two types of lung disorders with unknown etiology. One is a disease where multiple nodules are present throughout the lungs and the second disorder is when cavities in the upper parts of the lungs mimic signs of tuberculosis. Bronchiectasis is common with this infection, which is a chronic dilation of the breathing tubes that may cause the MAC infection to set in. When mucus accumulates in the lungs and is not adequately cleared by coughing up the sputum, then this area invites infections.

The symptoms of MAC are non-specific and variable, but can include a cough (dry or productive of mucus, sometime coughing up blood), feeling of malaise and fatigue, weakness, some chest discomfort and possible shortness of breath.

The studies...

There have been studies that suggest that showerheads are harboring this bacteria and inhaled into the lungs. The study's lead author, Leah Feazel of the University of Colorado (Boulder) states that "one hundred years ago, people bathed, they didn't shower." The microorganisms of MAC harbor inside the showerheads and are sprayed into the air when used. Feazel says, "These tiny particles can go all the way into your deep lungs." Showerheads were taken from nine different cities and tested; discovering they all contained this form of bacteria.

Researchers have been studying how to disinfect showerheads to rid this bacteria. They claim cleaning them does not resolve the problem and makes matters worse . It seems that MAC is chlorine resistant, as bleach did not work. It has been recommended that people who may be at risk for this infection to take tub baths instead of showering. If showering is the only way to go, then it is a good idea to open a window for ventilation. During the study it was found that metal showerheads fostered less bacteria versus the plastic ones. Another option is to purchase cheap heads and change them often, like every couple of months.

How is MAC treated?

The MAC infection is tough and takes a long time to treat, plus there is no guarantee that the infection might not recur. Sputum samples are tested for evidence of the MAC infection. Several antibiotics are given over a period of time, the average being at least 18 months. For many the biggest problem is the cost of the medications and the side effects of long-term antibiotic use. The common antibiotics used are one or a combination of azithromycin, clarithromycin, rifabutin, ethambutol and streptomycin. The side effects are the usual ones with any antibiotic use such as GI upset, nausea, diarrhea, skin rashes and headaches. Since a patient must be on the drugs for a long period of time, routine blood tests need to be obtained to look for low blood cell counts, abnormal liver enzymes and decreased renal function.

How MAC affected my life...

For me, this MAC infection hits home as my recent chest x-rays and CT scans show small lung nodules and possible MAC infection So far I feel alright, but I need to be followed by a pulmonologist yearly for any changes. And yes, I'm staying away from the shower. Until showerheads can be made to be non-microbial or sanitized to kill off MAC, I'll revert to the tub.

References:

Discovery News - "Dangerous Pathogens Live In Showerheads"

UTHCSCT - "MAC Lung Disease" Frequently Asked Questions