Introduction: Nasopharyngeal carriage of pathogens is a significant source of transmission to other susceptible groups, notably older people. The nasopharynx is a key reservoir for bacterial pathogens that can cause upper respiratory tract infections in children. One of the most significant bacteria that colonize the nasopharynx is Haemophilus influenzae, which frequently causes sinusitis and acute otitis media (AOM). Six distinct polysaccharide capsules are available for H. influenzae, the most virulent of which is H. influenzae serotype b (Hib). Alternatively, H. influenzae can exist without a capsule (non-typeable H. influenzae). Hib was the most frequent cause of invasive H. influenzae disease in young children, including meningitis, until the Hib capsule was included in the H. influenzae vaccine and it was included in the national childhood vaccination programs in 1993. Through both direct and indirect (herd immunity) protection, the routine administration of Hib vaccinations resulted in a considerable drop in invasive Hib disease in all age groups. However, this also created space for an increase in non-typeable H. influenzae (NTHi) cases and non-b-serotype cases. Between 2017 and 2021, the majority (76.8%) of invasive H. influenzae strains in Belgium were reported as non-typeable. The aim of study was Importance of Haemophilus Influenzae Bacteria and Concerns of Drug Resistance.
Methods: The present study is titled The Importance of Haemophilus Influenzae Bacteria and Concerns of Drug Resistance which was done by searching scientific databases such as Science Direct, Springer, Google Scholar, and PubMed.
Results: According to the findings, invasive infections in children and the elderly during the same period were also found to be caused by typeable serotypes, including serotypes "f" (9.7%), "b" (5.8%), "a" (2.7%), "e" (1.1%), and "d" (0.4%). These findings highlight the significance of carrying out additional studies on the prevalent H. influenzae serotypes. Two distinct methods exist for H. influenzae strains to develop antibiotic resistance: either they produce the beta-lactamase enzymes needed to hydrolyze beta-lactam antibiotics, or they develop mutations in the genes that code for the penicillin-binding protein (PBP) protein. The diversity of mutations in the ftsI gene results in several profiles that can affect the beta-lactam antibiotics differently, making macrolides and quinolones more significant alternative treatment strategies. Mutations in the ftsI gene, which encodes PBP3, lower the binding affinity of beta-lactam antibiotics to PBP3. One issue with treating H. influenzae with beta-lactam antibiotics is beta-lactamase-negative ampicillin-resistant strains, or BLNAR. Sequencing of the ftsI gene has revealed specific amino acid alterations that result in the BLNAR phenotype Groups I, II, III, and III-like of BLNARS are distinguished by the patterns of amino acid mutations at particular locations. In comparison to groups I and II, groups III and III-like (also known as high-BLNAR) typically have a higher ampicillin MIC (greater level of ampicillin resistance). Globally speaking, high BLNARs are changing, although more quickly in Asia than in the USA and Europe.
Conclusion: As a result of this investigation, certain serotypes for carriage (serotype "e") and the invasive group (serotypes "a" and "b") were discovered, and biotypes I, II, and III are more commonly detected in both the carriage group and the invasive group. Furthermore, the carriage (DCC, AOM) group showed higher levels of antimicrobial resistance to the drugs under analysis than the invasive group did. The ftsI gene showed a greater degree of mutation in the strains from children with AOM than in the strains from children with DCC. Given the paucity of information on the dynamics of H. influenzae that persist in a population of vaccinated children, the current study aids in laying the foundation for understanding the dynamics of H. influenzae carriage in Belgian children. Given the potential consequences for treating H. influenzae infections in light of the emergence of beta-lactam antibiotic resistance, this work offers a crucial initial understanding of the traits of circulating H. influenzae strains. Changes in the microbiology and epidemiology of H. influenzae should be closely watched since they may result in antibiotic resistance-related clinical failure.
Keywords: Haemophilus influenzae, Antimicrobial, Drug resistance