title: Genotypic characteristics of Haemophilus influenzae isolates from pediatric pneumonia patients in Chengdu city, Sichuan, China.
abstract: Two hundred and seventy-three Haemophilus influenzae strains isolated from pediatric pneumonia patients in China were studied. We used Multilocus Sequence Typing (MLST) to analyze genotypic characteristics. All strains were biotyped and serotyped. Relatedness and patterns of genes among isolates were determined by the analysis of MLST and eBURST. H. influenzae primarily causes acute pneumonia in children under 1 year old. Nontypeable H. influenzae was responsible for most cases of pediatric pneumonia. All 273 strains were classified into eight biotypes. They mostly belonged to the I, II, and III biotypes (17.6%, 43.6%, and 22.7%, respectively). 62 strains (22.7%) produced beta-lactamase. We found 28 novel alleles. Fifty different STs were found by MLST, of which 39 were novel. These were ST477 through ST508 and ST521 through ST527. Group 17 and predicted founders 503 were new groups in this study. No STs correlated with strains from Korea, which is adjacent to China. The H. influenzae strains from China appeared to have heterogeneous ST types patterns which may be the reason no outbreaks or epidemics of H. influenzae infections have occurred in Chengdu city, Sichuan, China.
authors.affiliation: State Key Laboratory for Infectious Diseases Control and Prevention, National Institute for Communicable Disease Control and Prevention, Chinese Center for Diseases Control and Prevention, P.O. Box 5, Beijing 102206, P. R. China.
authors.forename: Guozhong
authors.initials: G
authors.lastname: Tian
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Machao
authors.initials: M
authors.lastname: Li
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Wang
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Zheng
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Li
authors.forename: Cheng
authors.initials: C
authors.lastname: Huang
authors.forename: Xuechun
authors.initials: X
authors.lastname: Li
authors.forename: Yongqiong
authors.initials: Y
authors.lastname: Xie
authors.forename: Li
authors.initials: L
authors.lastname: Xu
authors.forename: Hongyu
authors.initials: H
authors.lastname: Ren
authors.forename: Zhujun
authors.initials: Z
authors.lastname: Shao
mesh_terms: D015373:Bacterial Typing Techniques; D002681:China / Q000453:epidemiology; D005260:Female; D005838:Genotype; D006192:Haemophilus Infections / Q000453:epidemiology / Q000382:microbiology*; D006193:Haemophilus influenzae / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D006801:Humans; D007223:Infant; D008297:Male; D010802:Phylogeny; D018410:Pneumonia, Bacterial / Q000453:epidemiology / Q000382:microbiology*