Abstract
Outbreaks of anthrax occur sporadically in Australia and most commonly in the “anthrax belt”, a region which extends from southern Queensland through the centre of New South Wales and into northern Victoria. Little is known about the epidemiological links between Bacillus anthracis isolates taken from different outbreaks and the diversity of strains within Australia. We used multiple-locus variable-number tandem repeat analysis employing 25 markers (MLVA25) to genotype 99 B. anthracis isolates from an archival collection of Australian isolates. MLVA25 genotyping revealed eight unique genotypes which clustered within the previously defined A3 genotype of B. anthracis. Genotyping of B. anthracis strains from outbreaks of disease in Victoria identified the presence of multiple genotypes associated with these outbreaks. The geographical distribution of genotypes within Australia suggests that a single genotype was introduced into the eastern states of Australia, followed by the spread and localised differentiation of the pathogen (MLVA25 genotypes MG1-MG6) throughout the anthrax belt. In contrast, unexplained occurrences of disease in areas outside of this anthrax belt which are associated with different genotypes, (MLVA25 genotypes MG7 and MG8) indicate separate introductions of B. anthracis into Australia.
Highlights
Bacillus anthracis, the causative agent of anthrax, is a Gram-positive spore-forming bacterium affecting livestock and humans worldwide
Genetic Diversity of Bacillus anthracis Strains in Australia Using MLVA25
All eight Multiple-locus variable-number tandem repeat analysis (MLVA) patterns were related to strains within the previously defined A3 genotype based upon the MLVA8 typing system [5,17] (Figure 1)
Summary
The causative agent of anthrax, is a Gram-positive spore-forming bacterium affecting livestock and humans worldwide. Anthrax is endemic in many areas of the world [1], including Australia, and can impact the international trade of livestock and their products. Outbreaks of anthrax have been recorded in Australia for over 170 years, with the first occurrence of the disease confirmed at Leppington in New South Wales in 1847 and the first reported outbreak in Victoria in 1876 [2]. Outbreaks of anthrax in Australia have been largely confined to an area known as the “anthrax belt”, a region which extends from southern Queensland through the centre of New South Wales and into northern Victoria [3]. Sporadic occurrences of disease outside of this belt, as defined by Barro et al [3], do occur but are considered rare. Two notable incidents occurred in areas geographically distinct from the historical anthrax belt. One was located in Queensland on the Marlborough Peninsula, over 750 km further north of the belt, and the second in Walpole, Western
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.
