ABSTRACT
OBJECTIVE: The purpose of this study was to find data proving the influence of the Haemophilus influenzae type b (Hib) conjugate vaccination on the frequency of invasive Hib illness. METHODOLOGY: A systematic literature search was conducted on the PubMed database to identify peerreviewed publications pertaining to the epidemiology of Haemophilus influenzae meningitis, both before and after the introduction of Haemophilus influenzae type b (Hib) conjugate vaccines. The search query employed a combination of relevant keywords, including "invasive," "Haemophilus," "influenzae," "meningitis," and specific serotype b (Hib). Additionally, terms related to epidemiology, burden, risk factors, impact, Hib vaccine, Hib conjugate vaccine, combination vaccine, vaccine production, efficacy, immunisation coverage, surveillance, review, clinical aspects, outcomes, and various age groups (adults and children) were incorporated. RESULT: The search encompassed articles published till now. Subsequently, relevant research papers concerning Haemophilus influenzae meningitis were subjected to a comprehensive review and analysis. CONCLUSION: The Hib conjugate vaccination has shown to be extremely effective when administered to the entire population. However, changes to the immunisation protocol appear to be required in order to effectively manage invasive Hib illness.