pediatrics
Croup
Etiology of Croup
Themost common pathogensare Parainfluenza Virus Infections , especially type 1 are Respiratory Syncytial Virus (RSV) and Human Metapneumovirus Infections (RSV) and Seasonal outbreaks are common. Cases caused by parainfluenza viruses tend to occur in the fall; those caused by RSV and influenza viruses tend to occur in the winter and spring. Spread is usually through the air or by contact with infected secretions. 