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Haemophilus influenzae Type b (Hib) 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
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Haemophilus influenzae type b (Hib) vaccines help prevent Haemophilus infections but not infections caused by other strains of H. influenzae bacteria. H. influenzae causes many childhood infections, including bacteremia, meningitis, pneumonia, sinusitis, otitis media, and epiglottitis.

For more information, see Hib Advisory Committee on Immunization Practices Vaccine Recommendations and Centers for Disease Control and Prevention (CDC): Hib Vaccination. A summary of changes to the 2021 adult immunization schedule is available here.

Preparations of Hib Vaccine

Hib vaccines are prepared from the purified capsule of Haemophilus influenzae type b (Hib). All Hib vaccines use polyribosylribitol phosphate (PRP) as the polysaccharide, but 4 different protein carriers are used in the 4 different Hib conjugate vaccines available:

  • Diphtheria toxoid (PRP-D)

  • Neisseria meningitidis outer membrane protein (PRP-OMP)

  • Tetanus toxoid (PRP-T)

  • Diphtheria mutant carrier protein CRM197 (HbOC)

PRP-D and HbOC vaccines are no longer available in the US.

Combination vaccines that contain Hib conjugate vaccines include DTaP-IPV/Hib (Pentacel®) and Hib-HepB (COMVAX®).

Indications for Hib Vaccine

The Hib vaccine is a routine childhood vaccination (see Table: Recommended Immunization Schedule for Ages 0–6 Years).

This vaccine is also recommended for

  • Adults with anatomic or functional asplenia and those scheduled for elective splenectomy if they are unimmunized (ie, if they have not previously received a primary series plus booster dose or ≥ 1 dose of Hib vaccine after age 14 months), although some experts suggest giving a dose before elective splenectomy regardless of vaccination history

  • Immunocompromised adults (eg, because of cancer chemotherapy or HIV infection) if they are unimmunized

  • People who have had a hematopoietic stem cell transplantation regardless of their vaccination history

Contraindications and Precautions of Hib Vaccine

The main contraindication for Hib vaccines is

  • A severe allergic reaction (eg, anaphylaxis) after previous dose or to a vaccine component

The main precaution with Hib vaccines is

  • Moderate or severe illness with or without a fever (vaccination is postponed until the illness resolves)

Dose and Administration of Hib Vaccine

The Hib vaccine dose is 0.5 mL IM. A primary childhood series is given in 3 doses at age 2, 4, and 6 months or in 2 doses at age 2 and 4 months, depending on the formulation. In either case, a booster is recommended at age 12 to 15 months.

One dose is given to older children, adolescents, and adults who have asplenia or who are scheduled for an elective splenectomy if they are unimmunized. Some experts suggest giving a dose before elective splenectomy regardless of vaccination history. The dose is given ≥ 14 days before elective splenectomy if possible.

A 3-dose regimen is given 6 to 12 months after hematopoietic stem cell transplantation; doses are separated by ≥ 4 weeks.

Adverse Effects of Hib Vaccine

Adverse effects are rare. They can include pain, redness, and swelling at the injection site and, in children, fever, crying, and irritability.

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.

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NOTE: This is the Professional Version. CONSUMERS: Click here for the Consumer Version
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