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Inducing Meningococcal Meningitis Serogroup C in Mice via Intracisternal Delivery
10:03

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[Haemophilus influenzae type a as the causative agent of meningitis in an infant]

D C Mulder1, R D Padberg, M Westra

  • 1Afd. Kindergeneeskunde, Zaans Medisch Centrum, Koningin Julianaplein 58, 1502 DV Zaandam.

Nederlands Tijdschrift Voor Geneeskunde
|September 18, 2002
PubMed

Insights

Haemophilus influenzae type b vaccination has reduced type b infections but may increase type a invasive infections. A case of meningitis caused by H. influenzae type a highlights this emerging public health concern.

Area of Science:

  • Pediatrics
  • Infectious Diseases
  • Vaccinology

Background:

  • The widespread use of conjugated Haemophilus influenzae type b (Hib) vaccine has dramatically reduced invasive Hib infections.
  • Hib vaccination is not known to provide cross-protection against other Hib serotypes.

Observation:

  • A fully vaccinated 6-month-old infant developed meningitis due to Haemophilus influenzae type a (Hia).
  • This case represents one of the few reported Hia infections in the Netherlands since 1975.

Findings:

  • Invasive infections caused by H. influenzae type b have significantly declined post-vaccination introduction.
  • Non-type b H. influenzae, including Hia, may experience increased carrier rates and invasive infections due to reduced competition from Hib.

Implications:

  • The success of Hib vaccination may inadvertently lead to a rise in invasive infections caused by non-vaccine serotypes like Hia.
  • Enhanced surveillance for non-type b H. influenzae invasive infections is crucial following widespread Hib vaccination programs.

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