Q: What is walking pneumonia?
A: Walking pneumonia is an old term used to distinguish a milder type of pneumonia that comes on gradually from the more serious form that starts suddenly and is quickly debilitating. It’s called walking pneumonia because you can walk around with it, as opposed to being laid up in bed or in the hospital—though its symptoms (fatigue, headache, fever, and especially, dry cough) can last a couple of weeks or more and be very bothersome.
Pneumonia refers to inflammation of the alveoli (the air sacs in the lungs where gas exchange occurs), usually caused by microorganisms, especially bacteria and viruses. Any mild pneumonia can be considered “walking pneumonia,” but some doctors reserve the term for an “atypical” pneumonia often caused by Mycoplasma pneumoniae bacteria. In contrast, the more “typical” and severe form of pneumonia is often caused by Streptococcus pneumoniae (commonly called pneumococcal pneumonia).
The Centers for Disease Control and Prevention (CDC) estimates that about two million people a year in the U.S. contract pneumonia from Mycoplasma pneumoniae. Because the bacteria can be carried in droplets in the air (up to a distance of six feet or so), the illness is spread mainly by sneezing or coughing. It can also spread through hand contact and contact with surfaces or objects that carry the bacteria.
Mycoplasma pneumonia more often affects children and younger adults (whereas pneumococcal pneumonia is prevalent in children and the elderly). It can occur any time of the year, but it is more common in summer and fall, and there tend to be outbreaks every four to eight years. In some cases, the bacteria cause an immune reaction that affects the central nervous system, skin, joints, kidneys or red blood cells.
Usually the body’s immune system can combat the infection, but antibiotics (erythromycin or tetracycline, for instance) may be prescribed to speed recovery. There is no vaccine to prevent Mycoplasma pneumonia, as there is for pneumococcal pneumonia. The best way to avoid it is to take the same precautions you would to prevent other respiratory illnesses—namely washing your hands frequently and keeping your distance from anyone who is infected.