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Assessing Respiratory Immune Responses to Haemophilus Influenzae
Published on: June 29, 2021
Haemophilus influenzae type b meningitis in a vaccinated and immunocompetent child
Ana F Almeida1, Eunice Trindade1, Artur B Vitor2
1Department of Pediatrics, São João Hospital, Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal.
Insights
Invasive Haemophilus influenzae type b (Hib) disease remains a concern despite vaccination. This case highlights that even vaccinated children can develop Hib meningitis, emphasizing continued surveillance.
Area of Science:
- Pediatrics
- Infectious Diseases
- Vaccinology
Background:
- The conjugate vaccine significantly reduced invasive Haemophilus influenzae type b (Hib) disease incidence.
- Routine immunization schedules have made Hib infections rare.
Observation:
- A previously healthy, vaccinated 15-month-old girl presented with fever, vomiting, and signs of meningitis.
- Cerebrospinal fluid analysis revealed pleocytosis and elevated protein levels, consistent with bacterial meningitis.
Findings:
- Haemophilus influenzae type b (Hib) was identified as the causative agent in the cerebrospinal fluid.
- Despite vaccination and no apparent risk factors, the patient experienced invasive Hib disease, suggesting potential vaccine failure.
Implications:
- This case underscores the importance of maintaining high vaccination coverage rates for Hib.
- Continued surveillance and notification strategies are crucial for monitoring and controlling invasive Hib disease, even in vaccinated populations.
Abstract:
Invasive Haemophilus influenzae type b (Hib) disease decreased dramatically after the introduction of conjugate vaccine in routine immunization schedules. We report a case of a fifteen-months-old girl, previously healthy and vaccinated, admitted in the emergency room with fever and vomiting. She was irritable and the Brudzinski's sign was positive. The cerebrospinal fluid (CSF) analysis showed pleocytosis and high protein level. Empiric intravenous antibiotics (ceftriaxone and vancomycin) were administered for suspected bacterial meningitis during 10 days. Serotyping of the Haemophilus influenzae strain found in CSF revealed a serotype b. After one year of follow-up no Hib meningitis sequelae were noted. Despite vaccination compliance and absence of risk factors, invasive Hib disease can occur due to vaccine failure. Efforts to keep the low incidence of invasive Hib disease should be directed to the maintenance of high vaccination coverage rates, combined with the notification and surveillance strategies already implemented in each country.
