Human parainfluenza viruses (HPIVs) are a group of four distinct serotypes of singled strand, RNA viruses. The are the second most common cause of lower respiratory tract infection in smaller children. Repeated infection throughout the life of the host is not uncommon. Symptoms of later breakouts include upper respiratory tract illness as in a cold and sore throat. The incubation period of all four serotypes is 1 to 7 days. ...

GoldBamboo