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[Haemophilus influenzae bacterial meningitis: residual risk; case report]

M Guillot1, P Eckart, M Amiour

  • 1Service de pédiatrie, centre hospitalier Robert-Bisson, 14100 Lisieux, France. pedia@ch-lisieux.fr

Archives De Pediatrie : Organe Officiel De La Societe Francaise De Pediatrie
|October 31, 2001
PubMed
Abstract

Insights

Despite widespread vaccination, bacterial meningitis caused by Haemophilus influenzae remains a rare but possible threat. Non-encapsulated strains pose a residual risk, necessitating continued vigilance.

Area of Science:

  • Pediatric infectious diseases
  • Bacteriology
  • Vaccinology

Background:

  • Haemophilus influenzae (Hi) historically caused significant bacterial meningitis in children.
  • Widespread vaccination has dramatically reduced Hi meningitis incidence.
  • Vaccination targets encapsulated strains, but non-encapsulated strains also exist.

Observation:

  • A 19-month-old infant, fully immunized, presented with bacterial meningitis.
  • Cerebrospinal fluid analysis identified a non-encapsulated strain of Haemophilus influenzae (biotype III).
  • This case highlights infections beyond the scope of current vaccine targets.

Findings:

  • Bacterial meningitis due to Haemophilus influenzae, though rare, can still occur in vaccinated individuals.
  • Non-encapsulated Haemophilus influenzae strains represent a persistent etiological agent.
  • The epidemiology of bacterial meningitis has been altered but not eliminated by vaccination.

Implications:

  • Preventive inoculation strategies for Haemophilus influenzae have revolutionized meningitis control.
  • A residual risk of bacterial meningitis persists, even in fully immunized populations.
  • Surveillance and awareness of non-encapsulated strains are crucial for public health.

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