Can an adult get the Haemophilus influenzae type b (Hib) vaccine?

Haemophilus influenzae Type b (Hib) Vaccination in Adults

Most healthy adults do not need the Hib vaccine, but specific high-risk adults should receive it—particularly those with asplenia, sickle cell disease, or who are hematopoietic stem cell transplant recipients. 1

Who Should Receive Hib Vaccine as an Adult

Clear Indications (One Dose Required)

Adults with functional or anatomic asplenia (including sickle cell disease) who have not previously received Hib vaccine should receive one dose, ideally at least 14 days before elective splenectomy. 1, 2

• Unimmunized asplenic patients aged >59 months and adults require 1 dose of Hib conjugate vaccine 1, 2
• The same pediatric Hib conjugate vaccine formulation is used, administered intramuscularly 2
• Timing before splenectomy is critical—vaccination at least 14 days pre-procedure allows adequate immune response 2, 3

Hematopoietic Stem Cell Transplant Recipients

All stem cell transplant recipients require a 3-dose Hib series starting 6-12 months after successful transplant, regardless of prior vaccination history. 1

• Doses should be separated by at least 4 weeks 1
• This applies to all ages, not just children 1

Special Immunocompromised Populations

• HIV-infected children aged ≥60 months who are unimmunized should receive 1 dose 1
• HIV-infected adults are NOT recommended to receive Hib vaccine since their risk for Hib infection is low 1
• Patients receiving chemotherapy or radiation therapy may need revaccination if doses were given within 14 days of starting therapy or during therapy—repeat doses at least 3 months after therapy completion 1, 2

Who Does NOT Need Hib Vaccine

Healthy adults without specific risk factors do not require Hib vaccination. 1

• Hib conjugate vaccines are primarily licensed for children aged 6 weeks to 71 months 1
• No efficacy data support routine use in healthy older children and adults 1
• Previously unvaccinated children aged ≥60 months who are not high-risk are generally immune to Hib disease and do not require catch-up vaccination 1

Clinical Context and Rationale

The shift in Hib epidemiology following widespread childhood vaccination has changed the adult risk profile. 4, 5

• In the post-vaccine era, adults with secondary immunodeficiency face higher risk than in the past 4
• Studies show 29% of chronic renal failure patients, 20% of diabetics, and 55% of multiple myeloma patients lack protective Hib antibody levels 4
• However, formal guidelines have not extended recommendations to these populations beyond those with asplenia and stem cell transplant 1

Common Pitfalls to Avoid

• Do not confuse Hib vaccine with influenza vaccine—these are completely different vaccines for different pathogens 1
• Do not assume all immunocompromised adults need Hib vaccine—HIV-infected adults specifically do NOT need it 1
• Do not forget to vaccinate before splenectomy when possible—post-operative vaccination is less effective 2, 3
• Do not use live vaccines in immunocompromised patients—Hib conjugate vaccines are inactivated and safe 1

Practical Administration

The vaccine used is the same pediatric Hib conjugate vaccine (PRP-T or PRP-OMP formulations), given intramuscularly. 2

• No special adult formulation exists 2
• Administering the vaccine to high-risk adults is not contraindicated and shows good immunogenicity 1, 4
• For asplenic patients, Hib vaccination is part of a comprehensive vaccination strategy that also includes pneumococcal and meningococcal vaccines 2, 3