Prevention and Treatment of Haemophilus influenzae type b (Hib) Infections
The primary prevention strategy for Haemophilus influenzae type b (Hib) infections is routine vaccination according to the CDC Advisory Committee on Immunization Practices (ACIP) guidelines, with treatment of established infections requiring appropriate antibiotic therapy such as ceftriaxone. 1, 2
Prevention Through Vaccination
Routine Childhood Vaccination Schedule
- Infants should receive either a 3-dose primary series of PRP-T vaccine or a 2-dose primary series of PRP-OMP vaccine beginning at age 2 months 1
- The first dose can be administered as early as age 6 weeks 1
- A booster dose of any licensed conjugate Hib vaccine is recommended at age 12-15 months, at least 8 weeks after the most recent Hib vaccination 1
- For American Indian/Alaska Native infants, a 2-dose primary series with PRP-OMP vaccine is preferred due to earlier peak incidence of disease (4-6 months versus 6-7 months in other populations) 1
Catch-up Vaccination Guidelines
- For unvaccinated infants <7 months: 2 doses of PRP-OMP or 3 doses of PRP-T with minimum 4-week intervals, plus booster at 12-15 months 1
- For unvaccinated infants 7-11 months: 2 doses at least 4 weeks apart, plus final dose at 12-15 months or 8 weeks after second dose (whichever is later) 1
- For unvaccinated children 12-14 months: 2 doses 8 weeks apart 1
- For unvaccinated children 15-59 months: single dose only 1
- For unvaccinated children ≥60 months (5 years) who are not high-risk: no vaccination needed 1
Special Populations at High Risk
- Asplenic patients >59 months and adults: 1 dose if unimmunized 1, 3
- Patients undergoing elective splenectomy (≥15 months): 1 dose prior to procedure, ideally at least 14 days before surgery 3
- HIV-infected children ≥60 months: 1 dose if unimmunized 1, 3
- HIV-infected adults: Hib vaccination not recommended 1, 3
- Hematopoietic stem cell transplant recipients (all ages): 3 doses 4 weeks apart beginning 6-12 months post-transplant, regardless of prior vaccination history 1, 3
- Patients <60 months undergoing chemotherapy/radiation: If doses given within 14 days of starting therapy or during therapy, repeat doses starting 3 months after therapy completion 1, 3
Treatment of Hib Infections
Ceftriaxone is FDA-approved for treatment of various Hib infections including 2:
- Lower respiratory tract infections
- Acute bacterial otitis media
- Bacterial septicemia
- Bone and joint infections
- Meningitis
For Hib meningitis, ceftriaxone is the treatment of choice due to its excellent CNS penetration and activity against Haemophilus influenzae, including beta-lactamase producing strains 2, 4
Prompt recognition and treatment is particularly important in high-risk groups such as 4:
- Young children
- Elderly patients
- Patients with immunodeficiency
- Patients with impaired complement response (e.g., sickle cell disease, asplenia)
Impact of Hib Vaccination
- Hib vaccines have dramatically reduced the incidence of invasive Hib disease worldwide 5
- Before widespread vaccination, Hib was the leading cause of bacterial meningitis in young children 4
- Conjugate vaccines offer superior immunogenicity compared to earlier polysaccharide vaccines, especially in infants 6, 7
- Conjugate vaccines induce immunologic memory and may reduce oropharyngeal carriage of Hib bacteria 7
Common Pitfalls to Avoid
- Delaying vaccination beyond recommended schedule significantly delays protection - studies show only 6-9% of children receive pertussis and Hib vaccines according to recommended schedules 8
- Failing to recognize high-risk patients who need Hib vaccination despite being older than the routine vaccination age 3, 4
- Not completing the full vaccination series, which is necessary for optimal protection 1
- Overlooking the need for revaccination in certain immunocompromised patients, such as those undergoing chemotherapy or stem cell transplantation 1, 3