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Haemophilus influenzae (including Hib) is a bacterium that can cause a severe infection, occurring mostly in infants and children younger than five years of age. It can cause lifelong disability and be deadly. In spite of its name, Haemophilus influenzae bacteria do not cause influenza (the "flu").

There are six identifiable types of Haemophilus influenzae bacteria (a through f) and other non-identifiable types (called nontypeable). The one most people are familiar with is Haemophilus influenzae type b, or Hib. There's a vaccine that can prevent disease caused by Hib, but not the other types of Haemophilus influenzae bacteria.

Is Your Child Protected against Hib Disease?

Father comforting his crying infant.

Hib bacteria can cause severe diseases like meningitis, but Hib disease is vaccine-preventable. Your child should get the full series of Hib shots as an infant plus one booster shot at 12 through 15 months of age.



Girl sneezing.

Haemophilus influenzae bacteria, including Hib, are spread person-to-person by direct contact or through respiratory droplets like coughing and sneezing.


Hib Information Sheets

Hib fact sheets.