Parainfluenza virus infections in England and Wales.
D002648:Child; D002675:Child, Preschool; D004739:England / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D018184:Paramyxoviridae Infections / Q000453:epidemiology*; D012307:Risk Factors; D014852:Wales / Q000453:epidemiology