8 Symptoms of Legionnaire’s disease

Legionnaires disease is a form of atypical pneumonia which is caused by the bacterium Legionella spp. The condition got its name after the outbreak at American Legion convention in Philadelphia, where it was first identified in 1976.

The causing microorganism naturally lives in standing waters, but it can colonize air conditioners, hot water tanks, hot tubes, cooling towers, etc. People get infected by inhaling the aerosol, usually in places that have artificial ventilation. This microorganism cannot be transmitted from one person to another, which is an important fact because if there are multiple cases of Legionnaires disease, the most reasonable step would be to check water supplies and air conditioners.

Symptoms usually occur after 7 to 10 days of incubation, and the recovery begins 4 to 5 days after the onset of the symptoms. Full recovery time takes a couple of months.

Diagnosis of Legionnaire’s disease can be difficult sometimes because clinical and radiological signs are nonspecific. The gold standard is culture diagnosis, but it requires 7 to 10 days to obtain a positive result. Because of that,  doctors nowadays use a simple urine test that detects Legionella urinary antigen. Legionnaires disease is a serious condition and the key to successful recovery is early diagnosis and treatment.

Common symptoms are:

1. Fever

In the early stages of Legionnaire’s disease, a patient will feel cold, the pale skin pale, and shiver. As the condition progresses the body temperature increases, usually going over 40°C. High temperatures leads to exhaustion and severe headaches.

The second phase is the opposite, the temperature quickly lowers , they feel warm and sweat profusely. After a few hours, the temperature  increase/decrease cycle starts over again, but with the right medication these cycles can be successfully interrupted.

2. Headache

This is a common symptom with Legionnaire’s disease, and is related to the rise in body temperature. These headaches can be unbearable, but once the body temperature starts to go down after 4 or 5 days , the pain gradually decreases.

More symptoms on next page…

About Dr Alex Grbovic 9 Articles
Dr Aleksandar Grbović is a medical doctor from the Belgrade University, Faculty of Medicine. He is passionate about promoting medicine by bridging the gap between the patient’s and doctor’s point of view. Currently working in the biggest Occupational Medicine Institute in Serbia and attending the Radiology residency program.


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