Parainfluenza Viruses (hPIVS)

Human parainfluenza viruses (hPIVS) are among the most important respiratory pathogens in humans. Most first Infections with hPIV in children are symptomatic and many affect the lower respiratory tract manifesting as croup, bronchiolitis or pneumonia.   Reinfection occurs at all ages but is usually more mild and hence presents as an upper respiratory infection or common cold illness.  There are four hPIV types (1 through 4).   hPIV3 is  a common in the first year of life and more typically manifests as either bronchiolitis or pneumonia when involving the lower respiratory tract, while hPIV1 and hPIV2 are both common causes of infectious croup in slightly older preschool children. After respiratory syncytial virus (RSV), hPIVs are the second most common cause of bronchiolitis in young infants.  While there are no currently licensed vaccines to prevent hPIV infection or illness there are several candidate vaccines which include live-attenuated, subunit and mRNA approaches.   DHVI clinical investigators will be evaluating a candidate hPIV3 vaccine in the near future