Children are a common source of respiratory infection for adults.
D000328:Adult; D000368:Aged; D001249:Asthma / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D007223:Infant; D010290:Parents; D012008:Recurrence; D012141:Respiratory Tract Infections / Q000150:complications / Q000235:genetics*; D014777:Virus Diseases / Q000235:genetics