Not Found

Find information on medical topics, symptoms, drugs, procedures, news and more, written in everyday language.

Haemophilus influenzae Type b Vaccine

By William D. Surkis, MD, Clinical Associate Professor of Medicine; Director, Internal Medicine Residency Program, Jefferson Medical College; Lankenau Medical Center
Jerome Santoro, MD, Clinical Professor of Medicine; Chief, Department of Medicine, Jefferson Medical College; Lankenau Medical Center

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.


The Hib vaccine is given as an injection into a muscle. 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 adults who were not vaccinated as children and who are at increased risk of these infections, 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

Side Effects

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