Ask the Experts: Hib (Haemophilus influenzae type b): Vaccine Safety

There is an extremely rare risk of an unpredictable, serious allergic reaction (anaphylaxis) following administration of any vaccine. Most people have no side effects from Hib vaccination. Some experience fever or a mild reaction at the injection site, including redness, warmth, tenderness, or swelling. These side effects resolve without treatment within a day or two after vaccination.

All serious adverse events that occur after receipt of any vaccine should be reported to the Vaccine Adverse Event Reporting System (VAERS) (https://vaers.hhs.gov).