J.T. is a 6-year-old girl who comes home from school with a note from the school nurse indicating that a child in her kindergarten class has been diagnosed with chickenpox

J.T. is a 6-year-old girl who comes home from school with a note from the school nurse indicating that a child in her kindergarten class has been diagnosed with chickenpox. J.T.’s mother is quite concerned because J.T. has not been immunized with the varicella vaccine. She wants to know whether administration of the vaccine at this time will protect J.T. from becoming infected.