Hypotonic-hyporesponsive episode in a 7-month-old infant after receipt of multiple vaccinations

A 7-month-old boy became difficult to arouse, was limp and had blue extremities 8 hours after immunization with intravenous poliovirus, diphtheria-tetanus toxoids-acellular pertussis, Haemophilus influenzae type b-hepatitis B virus and pneumococcal vaccines. The hypotonic-hyporesponsive episode had resolved by the time the infant was seen in an emergency department I hour later. The report describes hypotonic-hyporesponsive episode, encourages reporting of vaccine-associated adverse events and discusses prognosis and implications for subsequent immunization.