FAMILY MEDICINE® COLUMN
By John C. Wolf, D.O.
Associate Professor of Family Medicine®
Ohio University College of Osteopathic Medicine

30 PERCENT OF THOSE WITH LEGIONNAIRE'S DISEASE DIE

Question: My neighbor got Legionnaire's disease and nearly died before they figured out what was wrong with him. I've read about Legionnaire's disease before, but my neighbor is the first person I've known that actually had this illness. How common is it, and how does one avoid catching it?

Answer: Legionnaire's disease is a type of pneumonia that can occur in epidemics. The illness received its name from an American Legion convention where a number of participants developed a severe pneumonia from an unknown cause. A team of experts struggled to save the lives of those afflicted and to identify the cause of this mysterious illness. Eventually a bacterium was identified as the causative agent and named after the group that brought it to public attention --Legionella.

This illness is actually fairly common. According to the Centers for Disease Control there are about 1,300 reported cases each year, but many more go unreported. It is estimated that up to 5 percent of pneumonia cases outside of hospitals or nursing homes are Legionnaire's disease. This puts your neighbor in an unfortunate, but not exclusive, group.

Legionnaire's disease is a serious illness. Early diagnosis and use of appropriate antibiotics usually produces a cure. However, up to 30 percent of individuals who contract this infection, particularly if there is a delay in starting the proper antibiotics, will die from it. So, your neighbor's difficult struggle with this infection is not unusual.

Most of the time when a person gets Legionnaire's disease, it's not part of a larger epidemic like the one that struck the American Legion convention. However, the epidemics have helped us understand that avoiding this illness requires some precautions on your part as well as some preventive steps by others. I'll try to explain them now.

Legionella bacteria require the correct mixture of water, temperature, air and nutrients to grow. Just the right combination of these factors can often be found in such places as air conditioning cooling towers, evaporative coolers, decorative water fountains, whirlpool spas, humidifiers, shower heads and tap-water faucets. The bacteria are carried to these devices in small air-born water droplets. Once the bacteria have found a "new home" with the proper combination of water, temperature and nutrients, they reproduce. Then, once they reproduce in sufficient numbers, they are subsequently spread by the fine water droplets created by these devices.

The problem of Legionella bacterial growth can be solved by proper cleaning of cooling towers, evaporative coolers, humidifiers, vaporizers and such. The chance of you having Legionella in your home can be reduced by simple scrubbing with soap and water. This scrubbing can be satisfactory for your shower at home, but best results are achieved by also adding a chlorine bleach to your cleaning water.

So, to reduce your risk of developing Legionnaire's disease, I'd recommend that you regularly clean any device in your home that makes a spray of water. I know of no easy way to be sure that the cooling towers in public places are cared for properly, but the risks they pose and those of other "water-spraying" devices are less than a few years ago. Understanding the conditions necessary for Legionella growth has led to new guidelines for cleaning and maintenance of decorative and functional equipment that use and spray water.

And one additional bit of advice is that you mention Legionnaire's disease to your doctor if you have a fever, cough and feel truly dreadful. You see, the tests that can quickly distinguish Legionnaire's Disease from another type of pneumonia are not readily available. The best way to insure prompt treatment with an antibiotic that will stop the illness is to help your doctor have a high degree of suspicion that Legionella may be the cause of your illness.

Family Medicine® is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, Grosvenor Hall, Athens, Ohio 45701.