Widespread of non‐typeable Haemophilus influenzae with high genetic diversity after two decades use of Hib vaccine in China

Abstract

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. AbstractBackground: The aim of this study was to analyze the microbiological characteristics of nasopharyngeal carriage Haemophilus influenzae isolates collected from children with respiratory infections in Beijing hospital and Youyang Hospital of China. Methods:The serotypes of all isolates were determined using latex agglutinated antisera (a-f). The minimum inhibitory concentrations (MICs) of 11 antibiotics were determined using E-test strips. For the beta-lactamase-negative ampicillin-resistant (BLNAR) isolates, ftsI gene was sequenced based on fragments amplified by PCR. STs of H influenzae isolates were determined by multi-locus sequence typing. Results:The overall carriage rate of H influenzae in the study population was 9.1% (362/3984). One hundred and ninety H influenzae isolates which were selected in our study were non-typeable (NTHi) and 44 (23.2%) of them were positive for β-lactamase.All isolates were susceptible to ceftriaxone and levofloxacin. Susceptibility rates to erythromycin and sulfamethoxazole-trimethoprim in Beijing were significantly higher than Youyang (P < .05). Thirty-six BLNAR isolates were identified. The MLST analysis showed 108 STs in 190 isolates, the most common of which were ST408 (11, 5.8%), ST914 (10, 5.3%), ST57 (9, 4.7%), and ST834 (6, 3.2%). Twelve STs were detected in both of the study sites, which covered 63 isolates. Conclusions:All isolates in the present study were NTHi, which suggested widespread of this type in China. The BLNAR isolates were detected more frequently than before. Because high genetic diversity of NTHi isolates of H influenzae exists worldwide, it is important to continuously monitor these bacteria in the future.

Molecular epidemiology and antimicrobial resistance of Haemophilus influenzae in Guiyang, Guizhou, China

“…However, in our study, 18 isolates of BLNAR were identified from 196 test isolates (9.2%). A former report in Shanghai, China, and Beijing, China, the detection rate of BLNAR strains was 11.76 and 18.9% ( 24 , 25 ). In other countries, especially, Japan, BLNAR strains prevalence was >40% ( 3 ).…”

Real-time multiple cross displacement amplification assay for rapid and sensitive detection of Haemophilus influenzae

“…H. influenzae remains a common cause of illness in children worldwide and account for a considerable proportion of deaths due to bacterial pneumonia ( 2021 ; Dong et al., 2020 ; Fu et al., 2021 ). Better access to rapid, effective, and reliable laboratory diagnosis is needed especially for definitive clinical diagnosis and timely treatment, which has a positive impact on the course of the infection ( Shooraj et al., 2019 ).…”

“…Moreover, H. influenzae could infect various parts of the human body, causing diseases such as meningitis, epiglottis, and septic arthritis ( Marrs et al., 2001 ; Shooraj et al., 2019 ; Fu et al., 2021 ). Children aged from 2 months to 5 years old were more susceptible to H. influenzae infections because of the incapacity of transplacental maternal antibodies to the newborns and the lack of “natural antibodies” for the older children and the adults ( Ladhani et al., 2012 ; Dong et al., 2020 ).…”

Invasive non-typeable Haemophilus influenzae infection due to endometritis associated with adenomyosis

“…Although H. influenzae typically colonizes the respiratory tracts, it has been reported that a few women might carry NTHi in their genital tracts [12]. The comparatively widespread nature of NTHi consequent to the use of Hib vaccine in recent years emphasizes the need to familiarize ourselves with this important pathogen [7,8]. Our present case not only involved a rare occurrence of an invasive H. influenzae infection associated with adenomyosis, but also presents several lessons for those dealing with infectious disease in their daily practices.…”

“…Although H. influenzae type b (Hib) is a notoriously virulent serotype of this species [4], the introduction of routine conjugate Hib vaccination led to a decrease in the number of cases of Hib infection [5]. Over the past decades, however, this decrease was paralleled by an increase in the frequency of non-typable H. influenzae (NTHi) infection, which now accounts for the majority of invasive H. influenzae infection cases [6][7][8][9].…”