What is the definition or description of: reaction to hib vaccine?

Hib vaccine reaction: Reaction to Hib vaccine: Mild reaction to shot includes local redness and fever. Usually occurs within 3 days of having injection. Major reaction: Such reactions from a vaccine are very rare, estimated at fewer than 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination. Major reaction include hives, swelling of the face and throat, difficulty breathing, a fast heartbeat, dizziness, and weakness. These would usually start a few minutes to a few hours after the vaccination.