Etiologic characteristics of 138 non-typeable Haemophilus influenzae isolates in Guangdong Province
PENG Shu-ping1, LI Bai-sheng2, LIU Mei-zhen2, LI Zhen-cui2, HE Dong-mei2, LIAO Guo-dong1
1. Maoming Municipal Center for Disease Control and Prevention, Maoming, Guangdong 525000, China; 2. Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, Guangdong 510300, China
Abstract：Objective To understand the molecular serotyping, multilocus sequence typing (MLST), drug resistance phenotypes and drug resistance genes of 138 clinical isolates of non-typeable Haemophilus influenzae (NTHi) in Guangdong Province. Methods A total of 138 isolates of Haemophilus influenzae isolated from outpatients and inpatients of differenthospitals in Guangdong Province from 2018 to 2019 were collected by the National Pathogenic Bacteria Identification Network Surveillance. The capsular genes and drug resistance genes were detected by PCR technique. At the same time, MLST was used to analyze the community distribution among the strains, and descriptive epidemiological method was employed to perform a retrospective analysis on the case data. Results The male-to-female detection ratio in the 138 clinical strains of Haemophilus influenzae was 1.68:1. Most of them were detected in children (52.90%) and the elderly (30.43%). The onset season was mainly in February-June. Serotyping showed that all the 138 strains were NTHi isolates, of which 35.51% (49/138) carried the TEM resistance gene, and the resistance gene subtypes could be divided into three alleles (including HAEM0118:8, HAEM0118:6 and HAEM0118:10). No ROB gene was detected. There were 54 ST types in MLST typing, 12 of which were newly discovered ST types. ST103, ST422, ST836 and ST57 were the main prevalent ST types. Conclusion The major serotype of the 138 clinical isolates of Haemophilus influenzae in some areas of Guangdong Province was NTHi, with TEM type carrying high β-lactam enzyme resistance. The results suggest that it is necessary to strengthen the monitoring of etiology and drug resistance of NTHi clinical infection strains, rationally use antibiotics, and emphasize and accelerate the development of NTHi vaccine and drug so as to prevent the outbreak of community infection after the formation of dominant clone of NTHi.
2022, Vol. 29 
