Human parainfluenza viruses (HPIVs) usually spread from an infected person to others through
- the air by coughing and sneezing
- close personal contact, such as touching or shaking hands
- touching objects or surfaces that have HPIVs on them then touching your mouth, nose, or eyes
People usually get HPIV infections in the spring, summer, and fall. For more information, see HPIV Seasons.