Walking pneumonia is spreading. Doctors share the tell-tale symptoms to look for, and varied ways to treat it.

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• Walking pneumonia infections rose nationwide as kids returned to school this fall.
• The infection can be tricky to diagnose, and testing is expensive.
• Doctors may choose different antibiotics to try first, working on a case-by-case basis.

A common infection known as "walking pneumonia" has been on an uptick across the US in recent months, especially among kids and teens.

The respiratory illness caused by mycoplasma pneumoniae...