Legionnaires Disease | FAQ
Legionnaire’s disease nearly killed me. My temperature was 107°F; I was at death’s door. I want to make sure that this never happens to me again. Is there any chance that the bacteria are still in my system, remaining a threat? – Deborah Newman
I am sorry that you had such a punishing experience with Legionnaires’ disease (LD), but I am also thankful that you survived since the mortality can be high. The answer to your question has only been clearly elucidated in the last decade. In 1978, when I saw my first case, we wondered if this could occur and our blood antibody tests suggested that it might have occurred in two patients. But, more complete studies with newer and more powerful lab tests have shown that once you are cured with antibiotics, the bacteria are cleared. So, you do not have to worry about this. We have data on the largest collection of patients with LD in the world and have followed them for many years. Somewhat to our surprise, virtually none of them have become reinfected. Apparently, they developed immunity with their first infection. It appears that you have some residual protection if you contract Legionnaire’s disease; however, the most effective method of prevention is stopping cigarette smoking. Smokers are much more likely to contract LD (as they are to contract other respiratory infections, including the flu). Fever exceeding 104.5 is a hallmark of LD, so you should thank your MD for making that fine diagnosis.
Answer provided by Victor L. Yu, MD, Professor of Medicine, Unviersity of Pittsburgh; Chief, Infectious Disease Section, VA Medical Center, Pittsburgh, PA, USA.