Abstract
BackgroundAnthrax is an acute zoonotic infectious disease caused by the bacterium known as Bacillus anthracis. From 26 July to 8 August 2015, an outbreak with 20 suspected cutaneous anthrax cases was reported in Ganquan County, Shaanxi province in China. The genetic source tracking analysis of the anthrax outbreak was performed by molecular epidemiological methods in this study.MethodsThree molecular typing methods, namely canonical single nucleotide polymorphisms (canSNP), multiple-locus variable-number tandem repeat analysis (MLVA), and single nucleotide repeat (SNR) analysis, were used to investigate the possible source of transmission and identify the genetic relationship among the strains isolated from human cases and diseased animals during the outbreak.ResultsFive strains isolated from diseased mules were clustered together with patients’ isolates using canSNP typing and MLVA. The causative B. anthracis lineages in this outbreak belonged to the A.Br.001/002 canSNP subgroup and the MLVA15-31 genotype (the 31 genotype in MLVA15 scheme). Because nine isolates from another four provinces in China were clustered together with outbreak-related strains by the canSNP (A.Br.001/002 subgroup) and MLVA15 method (MLVA15-31 genotype), still another SNR analysis (CL10, CL12, CL33, and CL35) was used to source track the outbreak, and the results suggesting that these patients in the anthrax outbreak were probably infected by the same pathogen clone.ConclusionsIt was deduced that the anthrax outbreak occurred in Shaanxi province, China in 2015 was a local occurrence.
Highlights
Anthrax is an acute zoonotic infectious disease caused by the bacterium known as Bacillus anthracis
Because single nucleotide repeat (SNR) markers can provide additional genetic resolution among B. anthracis strains of the same multiple-locus variable-number tandem repeat analysis (MLVA) genotype [14, 15], the SNR analysis has been used as a means of source tracking anthrax outbreaks [14]
The index patient was a 66-year-old male farmer, who slaughtered a dead mule on 26 July, with cutaneous anthrax appearing on his fingers on the same day
Summary
Anthrax is an acute zoonotic infectious disease caused by the bacterium known as Bacillus anthracis. The genetic source tracking analysis of the anthrax outbreak was performed by molecular epidemiological methods in this study. B. anthracis is a relatively homogeneous bacteria species with a demonstrated lack of polymorphism, which may be due to the long periods its endospores spend being dormant during its lifecycle [4] Genetic markers such as single-nucleotide polymorphisms (SNPs) have been used to illustrate the phylogenetic and evolutionary relationship of B. anthracis strains, which allows us to better understand how they fit into regional and global phylogeographic patterns [4, 5]. Other molecular typing methods, such as the multiple-locus variable-number tandem repeat analysis (MLVA) [6–8], have been used to illustrate the phylogenetic relationship of B. anthracis strains and for source tracking in the event of a bioterrorist attack or anthrax outbreak [3]. Because SNR markers can provide additional genetic resolution among B. anthracis strains of the same MLVA genotype [14, 15], the SNR analysis has been used as a means of source tracking anthrax outbreaks [14]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
