title: Streptococcus agalactiae isolates of serotypes Ia, III and V from human and cow are able to infect tilapia.
abstract: Recent studies have shown that group B streptococcus (GBS) may be infectious across hosts. The purpose of this study is to investigate the pathogenicity of clinical GBS isolates with serotypes Ia, III and V from human and cow to tilapia and the evolutionary relationship among these GBS strains of different sources. A total of 27 clinical GBS isolates from human (n=10), cow (n=2) and tilapia (n=15) were analyzed using serotyping, multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Among them, 15 isolates were tested for their pathogenicity to tilapia. The results showed that five human GBS strains (2 serotype III, 2 serotype Ia and 1 serotype V) infected tilapia with mortality rate ranging from 56.67% to 100%, while the other five human GBS strains tested were unable to infect tilapia. In addition, two cow GBS strains C001 and C003 of serotype III infected tilapia. However, they had significantly lower pathogenicity than the five human strains. Furthermore, human GBS strains H005 and H008, which had very strong ability to infect tilapia, had the same PFGE pattern. MLST analysis showed that the five human and the two cow GBS strains that were able to infect tilapia belonged to clonal complexes CC19, CC23 and CC103. The study for the first time confirmed that human or cow GBS clonal complexes CC19, CC23 and CC103 containing strains with serotypes Ia, III and V could infect tilapia and induce clinical signs under experimental conditions.
authors.affiliation: Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning 530021, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Chen
authors.affiliation: Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning 530021, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.affiliation: Liuzhou Aquaculture Technology Extending Station, Liuzhou 545006, China.
authors.forename: Fu-Guang
authors.initials: FG
authors.lastname: Luo
authors.affiliation: Guangxi Center for Disease Control and Prevention, Nanning 530021, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning 530021, China.
authors.forename: Wan-Wen
authors.initials: WW
authors.lastname: Liang
authors.affiliation: Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning 530021, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Huang
authors.affiliation: Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning 530021, China.
authors.forename: Ai-Ying
authors.initials: AY
authors.lastname: Lei
authors.affiliation: Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning 530021, China. Electronic address: ganxipaper@163.com.
authors.forename: Xi
authors.initials: X
authors.lastname: Gan
authors.affiliation: Guangxi Key Laboratory for Aquatic Genetic Breeding and Healthy Aquaculture, Guangxi Academy of Fishery Sciences, Nanning 530021, China. Electronic address: pinglili2000@163.com.
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Li
mesh_terms: D000818:Animals; D002417:Cattle; D005260:Female; D006801:Humans; D058885:Multilocus Sequence Typing; D065288:Serogroup; D012703:Serotyping; D013290:Streptococcal Infections / Q000382:microbiology / Q000662:veterinary*; D013292:Streptococcus agalactiae / Q000145:classification* / Q000235:genetics; D017210:Tilapia
keywords: Cow; Human; MLST; PFGE; Pathogenicity; Streptococcus agalactiae; Tilapia