The Centers for Disease Control has issued an alert due to an upswing – most noticeably in pediatric cases – of mycoplasma pneumoniae, the cause of what’s commonly known as “walking pneumonia.”

According to the CDC, cases of walking pneumonia increased in the U.S. in late spring and has remained high. While cases have been increasing across all age groups, it has grown the most among children, up from 1% to 7.2% among children ages 2-4 and 3.6% to 7.4% among children ages 5-17.

The increase in children ages 2-4 is particularly notable because M. pneumoniae historically hasn’t been recognized as a leading cause of pneumonia in this age group, the CDC said.

Symptoms

Most symptoms of walking pneumonia are generally mild and appear like other respiratory viruses, such as a chest cold, with fever, cough and a sore throat. Symptoms appear gradually but can progress to pneumonia and, in rare cases, can result in hospitalization. Younger children can have different symptoms, the CDC explained, including diarrhea, wheezing and vomiting.

It can take one to four weeks to symptoms to appear after someone’s been exposed to the bacteria. Symptoms can last for several weeks, though the length and severity vary.

Chest cold symptoms

• Feeling tired
• Fever
• Headache
• Slowly worsening cough
• Sore throat
  

Younger children may have different symptoms

Instead of chest cold symptoms, children younger than 5 years old may have:

• Diarrhea
• Sneezing
• Sore throat
• Stuffy or runny nose
• Vomiting
• Watery eyes
• Wheezing

Walking pneumonia symptoms

• Cough
• Feeling tired
• Fever and chills
• Shortness of breath

Why is it called “walking pneumonia?”

The name walking pneumonia comes from the severity of the symptoms.

People with pneumonia caused by M. pneumonia can seem better than you would expect for someone with a lung infection. The mild symptoms mean someone may not stay home or in bed, leading it to be called “walking pneumonia,” the CDC explained.

It’s spread by inhaling respiratory droplets from when an infected person coughs or sneezes. The best prevention, the CDC said, is washing your hands frequently and covering coughs and sneezes.