Cases of “walking pneumonia” have risen sharply across the U.S. since last spring. It is called walking pneumonia because children and adults who contract it seem better than expected for someone with a lung infection. 

It is caused by the bacteria Mycoplasma pneumoniae, which has a different structure than most bacteria. It does not have a cell wall, which defines a bacteria’s shape—it can have many shapes, and under a microscope can even look like fried eggs.

It can be treated with antibiotics other than penicillin, because penicillins target the bacterial cell walls that Mycoplasma lacks. 

Although walking pneumonia can occur at any age, it most often occurs among children ages six to 17, with a notable increase seen in children between ages two and four.

Outbreaks occur mostly in crowded environments such as schools and meeting places. Once you contract it (through breathing in respiratory droplets containing the bacteria), it can incubate in the body for between one to four weeks until symptoms occur. 

Symptoms include sore throat, cough, headache, mild chills and a low-grade fever.

The U.S. Centers for Disease Control (CDC) says that while uncommon, serious complications from infection can occur. Those can require hospital care. 

Parents, be aware of your child having a fever, headache and a persistent or worsening cough. Take the child to the doctor before more serious complications occur. 

Michael Kossove is professor emeritus and adjunct professor of microbiology at Touro University, School of Health Sciences. He is a certified specialist in public health and medical microbiology.