RSV

The common respiratory virus causes mild flu-like symptoms in most people but can lead to more severe illness and even hospitalization in children under 1 year old.

The latest spike is months early and it's pushing care facilities to capacity. Children under the age of 5 are most vulnerable.

Sick kids are crowding emergency rooms in parts of the country and some pediatric hospitals say they're running out of beds.

It's impossible to miss all the reminders that flu season is here, from ads at your local pharmacy to gentle reminders to cover up when you cough or…