NCIt definition : A non-taxonomic group of paramyxoviruses that are cause of respiratory tract infections
in humans. Infection is most common in infants and young children and symptoms may
include fever, runny nose, and cough. Infection is usually self-limiting but can also
cause more severe illness, such as croup or pneumonia.;
Alternative definition : CDISC: Any viral organism that can be assigned to the species Human Parainfluenza
virus 1, 2, 3 and/or 4.;