The nurse is instructing the parents of a 5-year-old child receiving a MMR vaccine about possible serious reactions. Which of the following is considered a serious reaction? SELECT ALL THAT APPLY

A. Prolonged seizures are a serious reaction and require immediate medical attention. B. Decreased level of consciousness is a serious reaction and requires immediate medical attention. C. Low grade fever is a common and mild reaction to vaccines. D. Fussiness and crying are common and mild reactions to vaccines. E. Redness at the site is a common and mild reaction to vaccines.