Open AccessWidespread of non‐typeable Haemophilus influenzae with high genetic diversity after two decades use of Hib vaccine in China
Author(s) -
Dong Qiaoli,
Shi Wei,
Cheng Xiaoping,
Chen Changhui,
Meng Qinghong,
Yao Kaihu,
Qian Suyun
Publication year - 2020
Publication title -
journal of clinical laboratory analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.536
H-Index - 50
eISSN - 1098-2825
pISSN - 0887-8013
DOI - 10.1002/jcla.23145
Subject(s) - haemophilus influenzae , multilocus sequence typing , hib vaccine , microbiology and biotechnology , biology , carriage , ampicillin , serotype , sulfamethoxazole , population , erythromycin , molecular epidemiology , virology , genotype , pasteurellaceae , antibiotics , genetics , medicine , gene , environmental health , pathology
Background 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.