Long Term Impact of Conjugate Vaccines on <i>Haemophilus influenzae</i> Meningitis: Narrative Review

• Main Author: Mary Paulina Elizabeth Slack
• Format: Article
• Language: English
• Published: MDPI AG 2021-04-01
• Series: Microorganisms
• Subjects: <i>Haemophilus influenzae</i>; Hib; impact of Hib conjugate vaccine; Hia; NTHi
• Online Access: https://www.mdpi.com/2076-2607/9/5/886

<i>H. influenzae</i> serotype b (Hib) used to be the commonest cause of bacterial meningitis in young children. The widespread use of Hib conjugate vaccine has profoundly altered the epidemiology of <i>H. influenzae</i> meningitis. This short review reports on the spectrum of <i>H. influenzae</i> meningitis thirty years after Hib conjugate vaccine was first introduced into a National Immunization Program (NIP). Hib meningitis is now uncommon, but meningitis caused by other capsulated serotypes of <i>H. influenzae</i> and non-typeable strains (NTHi) should be considered. <i>H. influenzae</i> serotype a (Hia) has emerged as a significant cause of meningitis in Indigenous children in North America, which may necessitate a Hia conjugate vaccine. Cases of Hie, Hif, and NTHi meningitis are predominantly seen in young children and less common in older age groups. This short review reports on the spectrum of <i>H. influenzae</i> meningitis thirty years after Hib conjugate vaccine was first introduced into a NIP.