Legionnaires’ disease is a severe form of pneumonia. This disease is an uncommon but serious disease. It is an acute respiratory infection caused by Legionella bacteria. Although the disease has been around even before 1976, it was first identified after an outbreak of severe pneumonia happened at an American Legion’s Philadelphia convention that year. Most people who are exposed to the Legionella bacteria do not become ill. Middle-aged and older people are more susceptible to this disease. The disease has also been reported in children although less severe. Smokers and persons with chest problems are more commonly affected. People who have weak immune systems due to diseases like kidney failure, diabetes, and cancer are also more likely to get infected. Men are more frequently infected with Legionnaires’ disease than women. People get infected with Legionnaires’ disease from inhaling the bacteria and not from person-to-person contact. They get infected with the disease when they inhale mists or small droplets of water suspended in the air which contain the bacteria.
The Legionella bacteria are usually found living in natural water systems. The bacteria flourish in warm, damp environments. They can survive for a long time in rivers, hot springs, soil, and lakes. Bacteria from these natural environments do not really cause any problem since the levels are so low. The bacteria living indoors such as those in whirlpool spas, hot water systems, air-conditioning systems, evaporative condensers, and other purpose-built systems pose more threat to our health. Most outbreaks occur in large buildings mainly because its complex systems allow the Legionella bacteria to thrive and spread more easily.
Legionnaires’ disease has symptoms that are like those of other forms of pneumonia. At first, it can be difficult for healthcare providers to diagnose the disease since the symptoms are to those of flu. The disease usually develops symptoms 2 to 14 days after being exposed to the Legionella bacteria. The first signs and symptoms of the disease are fever that may be 104 ̊F or higher. During the second or third day, other signs and symptoms of Legionnaires’ disease may develop. These include: fatigue, cough, chest pain, loss of appetite; shortness of breath; gastrointestinal symptoms (diarrhea, vomiting, and nausea); and confusion or other mental changes. The disease primarily affects the lungs and can sometimes cause infections to wounds and in other parts of the body such as the heart.
Special tests are needed to distinguish Legionnaires’ disease from the other types of pneumonia. The tests that may be done on the patient to know if he is infected with Legionnaires disease are the following: urine tests to check for the presence of Legionella pneumophila bacteria; chest x-ray to be able to show the extent of the infection in the lungs; test the sputum or lung tissue sample for the Legionella bacteria; blood tests for a complete blood count (CBC) and white blood cell count; test for arterial blood gases; and CT scan for the brain or spinal tap to check for neurological symptoms.
Legionnaires’ disease is treated with antibiotics to fight the infection. Healthcare providers should not wait for confirmation from lab tests before giving medication for the disease. Treatment for the disease should immediately be done if infection is suspected. Immediate medication can help avoid any chance of serious complications and even death.
