Feeling run down but not "sick enough" to stay in bed? You might have a condition dubbed "walking pneumonia." This mild yet persistent form of pneumonia often sneaks up on people, leaving them with cold-like symptoms they try to power through.

Between May and October, the number of 2 to 4 year olds diagnosed after visiting the ER for a pneumonia-related illness has jumped from one to 7%.

Dr. Vin Gupta joins José Díaz-Balart to describe everything you need to know about the rise of "walking pneumonia" and other winter illnesses.

Walking pneumonia is a mild lung infection caused by bacteria like Mycoplasma pneumoniae, often mistaken for a lingering cold due to overlapping symptoms. Walking pneumonia might not send you to bed,

Cases of walking pneumonia, a bacterial infection, have been on the rise in Michigan, according to the Centers for Disease Control and Prevention.