Signs and Symptoms

A grandmother reading to her sick grandson

Children who get Mycoplasma pneumoniae infection usually have signs that appear more like a cold than pneumonia.

In general, illness caused by Mycoplasma pneumoniae is mild with symptoms that appear and get worse over a period of 1 to 4 weeks. These bacteria can cause several types of infections.

The most common type of illness, especially in children, is tracheobronchitis, commonly known as a chest cold. Common symptoms of a chest cold include:

  • Sore throat
  • Fatigue (being tired)
  • Fever
  • Slowly worsening cough that can last for weeks or months
  • Headache

Experts have estimated that up to 1 in 10 people who get ill from M. pneumoniae get pneumonia. Common symptoms of pneumonia include:

  • Cough that may produce mucus
  • Fever and chills
  • Shortness of breath
  • Chest pain
  • Fatigue

Children younger than 5 years old often do not run a fever when they have an illness caused by M. pneumoniae. Instead they may have signs that appear more like a cold than pneumonia. They sometimes wheeze, vomit, or have diarrhea.