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Haemophilus influenzae Type b Vaccine


Margot L. Savoy

, MD, MPH, Lewis Katz School of Medicine at Temple University

Last full review/revision Jun 2021| Content last modified Jun 2021

The Haemophilus influenzae type b (Hib) vaccine helps protect against bacterial infections due to Hib, such as pneumonia and meningitis. These infections may be serious in children. Use of the vaccine has decreased the incidence of serious Hib infections in children by 99%. These infections are uncommon in adults with a healthy immune system and a functioning spleen.

Different formulations of the vaccine are available.

For more information, see the Centers for Disease Control and Prevention's (CDC) Haemophilus Influenzae type b (Hib) vaccine information statement.

(See also Overview of Immunization.)


The Hib vaccine is given as an injection into a muscle. As a part of routine childhood vaccination, doses are given at age 2 months and 4 months or at age 2 months, 4 months, and 6 months, depending on which formulation is used. In either case, a final dose is given at age 12 to 15 months (for a total of three or four doses).

All children should be vaccinated.

The Hib vaccine is also recommended for older children, adolescents, and adults who were not vaccinated and who are at increased risk of this infection, such as the following:

  • People who do not have a functioning spleen
  • People who have a weakened immune system (such as those with AIDS)
  • People who have had chemotherapy for cancer
  • People who have had stem cell transplantation

If people have a temporary illness, doctors usually wait to give the vaccine until the illness resolves (see also CDC: Who Should NOT Get Vaccinated With These Vaccines?).

Side Effects

Occasionally, the injection site becomes sore, swollen, and red. After being vaccinated, children may have a fever, cry, and be irritable.

More Information

The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  • Centers for Disease Control and Prevention (CDC): Information statement about the Hib vaccine
  • CDC: Information about people who should NOT get vaccinated with the Hib vaccine

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