Season One Edit. Beckett's initial relationship with Castle was strained because she viewed him as immature and reckless. She suspected (correctly) that Castle was using his research as an excuse to pursue her, and only tolerated his presence at the request of Captain Montgomery.
What causes croup in children. Croup in children is most often caused by the parainfluenza virus, a respiratory virus not related to the flu. But it can also be caused by other respiratory viruses including the flu. Yes, croup is contagious.
Epidemiology. Croup is the most common pediatric illness that causes acute stridor, accounting for approximately 15% of clinic and emergency department visits for pediatric respiratory tract infections. It is primarily a disease of infants and toddlers, with a peak incidence from age 6 months to 36 months (3 years).ge. Primarily a disease of infants and toddlers, croup has a peak incidence from age 6-36 months (3 y). In North America, incidence peaks during the second year of life, at 5-6 cases per 100 children. Although uncommon after age 6 years, croup may be diagnosed in the preteen and adolescent years and rarely in adults.