Pediatric cases of Mycoplasma pneumoniae-associated pneumonia, which can cause "walking pneumonia," have been rising over the last six months, according to the CDC.
The agency recommends clinicians be aware of these infections, consider swabbing patients' throats and nasopharynx for better detection, and consider using a second-line antibiotic — fluoroquinolones or tetracyclines — for patients not improving with the first-line treatment, macrolides.
Since late spring, bacterial infections caused by M. pneumoniae have increased, peaking in late August, the CDC said Oct. 18. The bacterium can damage the lining of the respiratory tract, and most M. pneumoniae infections are mild, presenting mainly as a chest cold.
For pneumonia cases, the CDC said these are often a milder form known as "walking pneumonia."
"People with pneumonia caused by M. pneumoniae can seem better than expected for someone with a lung infection," the agency said. "With mild symptoms, people may not stay home or in bed. Thus, the phrase 'walking pneumonia' was coined."
Infections most commonly occur among children ages 5 to 17 and young adults, but recently, the United States has reported an increase among children younger than 5. These children may present different symptoms, including diarrhea, wheezing or vomiting.
Between March 31 and Oct. 5, the percentage of M. pneumoniae diagnoses rose from 1% to 7.2% in children ages 2 to 4 and from 3.6% to 7.4% in children ages 5 to 17.