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Stephen C Barker - One of the best experts on this subject based on the ideXlab platform.
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climatic requirements of the eastern paralysis tick Ixodes holocyclus with a consideration of its possible geographic range up to 2090
International Journal for Parasitology, 2021Co-Authors: Ernest J M Teo, Dayana Barker, Melanie N Vial, Semira Hailu, Samuel Kelava, Myron P Zalucki, Michael J Furlong, Stephen C BarkerAbstract:Abstract The eastern paralysis tick, Ixodes holocyclus, is an ectoparasite of medical and veterinary importance in Australia. The feeding of I. holocyclus is associated with an ascending flaccid paralysis which kills many dogs and cats each year, with the development of mammalian meat allergy in some humans, and with the transmission of Rickettsia australis (Australian scrub typhus) to humans. Although I. holocyclus has been well studied, it is still not known exactly why this tick cannot establish outside of its present geographic distribution. Here, we aim to account for the presence as well as the absence of I. holocyclus in regions of Australia. We modelled the climatic requirements of I. holocyclus with two methods, CLIMEX, and a new envelope-model approach which we name the ‘climatic-range method’. These methods allowed us to account for 93% and 96% of the geographic distribution of I. holocyclus, respectively. Our analyses indicated that the geographic range of I. holocyclus may not only shift south towards Melbourne, but may also expand in the future, depending on which climate-change scenario comes to pass.
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Survey of cases of tick-paralysis and the presence of the eastern paralysis tick, Ixodes holocyclus, and the southern paralysis tick, Ixodes cornuatus, in the Greater Melbourne Area.
Australian veterinary journal, 2019Co-Authors: Dayana Barker, Stephen C BarkerAbstract:The objective of this study was to test the hypothesis that the paralysis ticks, Ixodes holocyclus and Ixodes cornuatus, are epizootic and/or enzootic in the Greater Melbourne Area (GMA). We examined the ticks in the museum collections of Australia, wrote to, phoned and visited veterinarians and other colleagues in the GMA to gather information about the cases of tick paralysis and to request the ticks for identification. We present evidence of I. holocyclus at 24 postcodes and I. cornuatus at 28 postcodes in the GMA. We found evidence that I. holocyclus is epizootic at four postcodes in the GMA: at East Melbourne, Williamstown, Moonee Ponds and Hoppers Crossing. We did not find evidence that I. holocyclus is enzootic in the GMA. I. cornuatus is apparently enzootic in the GMA at Bullengarook, Kinglake, Chum Creek and Healesville. Our hypothesis is that I. cornuatus is also enzootic at Mt Macedon, Gisborne and at other bushy postcodes in the GMA. Since this tick is apparently enzootic in the GMA, it may also be epizootic at postcodes adjacent to busy postcodes such as Bullengarook, Kinglake, Chum Creek and Healesville. The concept of hitch-hiker larvae, nymphs and adult female ticks may explain many of the cases of tick paralysis due to I. holocyclus in the GMA. The accurate assessment of the risk of tick paralysis in dogs and cats in the GMA requires a more detailed map of the distribution of I. holocyclus and I. cornuatus in Victoria.
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Discovery of a novel iflavirus sequence in the eastern paralysis tick Ixodes holocyclus
Archives of Virology, 2018Co-Authors: Caitlin A. O’brien, Jody Hobson-peters, Sonja Hall-mendelin, Andy Allen, Ala Lew-tabor, Dayana Barker, Stephen C Barker, Manuel Rodriguez-valle, Georgia Deliyannis, Roy A. HallAbstract:Ixodes holocyclus , the eastern paralysis tick, is a significant parasite in Australia in terms of animal and human health. However, very little is known about its virome. In this study, next-generation sequencing of I. holocyclus salivary glands yielded a full-length genome sequence which phylogenetically groups with viruses classified in the Iflaviridae family and shares 45% amino acid similarity with its closest relative Bole hyalomma asiaticum virus 1. The sequence of this virus, provisionally named Ixodes holocyclus iflavirus (IhIV) has been identified in tick populations from northern New South Wales and Queensland, Australia and represents the first virus sequence reported from I. holocyclus.
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a list of the 70 species of australian ticks diagnostic guides to and species accounts of Ixodes holocyclus paralysis tick Ixodes cornuatus southern paralysis tick and rhipicephalus australis australian cattle tick and consideration of the place of a
International Journal for Parasitology, 2014Co-Authors: Stephen C Barker, A R Walker, Dayana CampeloAbstract:Seventy species of ticks are known from Australia: 14 soft ticks (family Argasidae) and 56 hard ticks (family Ixodidae). Sixteen of the 70 ticks in Australia may feed on humans and domestic animals (Barker and Walker 2014). The other 54 species of ticks in Australia feed only on wild mammals, reptiles and birds. At least 12 of the species of ticks in Australian also occur in Papua New Guinea. We use an image-matching system much like the image-matching systems of field guides to birds and flowers to identify Ixodes holocyclus (paralysis tick), Ixodes cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). Our species accounts have reviews of the literature on I. holocyclus (paralysis tick) from the first paper on the biology of an Australian tick by Bancroft (1884), on paralysis of dogs by I. holocyclus, to papers published recently, and of I. cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). We comment on four controversial questions in the evolutionary biology of ticks: (i) were labyrinthodont amphibians in Australia in the Devonian the first hosts of soft, hard and nuttalliellid ticks?; (ii) are the nuttalliellid ticks the sister-group to the hard ticks or the soft ticks?; (iii) is Nuttalliella namaqua the missing link between the soft and hard ticks?; and (iv) the evidence for a lineage of large bodied parasitiform mites (ticks plus the holothyrid mites plus the opiliocarid mites).
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Identification of Ixodes holocyclus by DNA sequencing: Application for suspected tick envenomation in a dog living outside an enzootic area
Australian Veterinary Practitioner, 2012Co-Authors: Kylie Kelers, Stephen C Barker, S. D. SongAbstract:This report describes the use of DNA sequencing to identify Ixodes holocyclus as the cause of suspected tick paralysis in a dog that lived outside an enzootic area. The dog had not recently visited a known enzootic area or a predicted core area for this species of tick. Species differentiation of paralysis ticks, I. holocyclus and I. cornuatus can be difficult. The use of DNA sequences to definitively identify the species of tick causing paralysis in Victoria will allow new information to be gained about the distribution of I. holocyclus and I. cornuatus and assist in identifying differences in clinical disease caused by these species. This case also serves as a reminder that vector-borne diseases should be considered as a differential diagnosis despite the animal living outside a known enzootic area.
Alexander W Gofton - One of the best experts on this subject based on the ideXlab platform.
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NGS coverage and relative abundance of taxonomically assigned sequence reads obtained from koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:NGS coverage and relative abundance of taxonomically assigned sequence reads obtained from koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
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Comparison of prevalence estimates of Trypanosoma spp. obtained using NGS and Sanger sequencing in koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:Comparison of prevalence estimates of Trypanosoma spp. obtained using NGS and Sanger sequencing in koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
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Prevalence of known genotypes of T. copemani and T. vegrandis in koalas and ticks (Ixodes holocyclus and Ixodes tasmani), determined by NGS at the 18S rRNA locus.
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:Prevalence of known genotypes of T. copemani and T. vegrandis in koalas and ticks (Ixodes holocyclus and Ixodes tasmani), determined by NGS at the 18S rRNA locus.
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Increased genetic diversity and prevalence of co-infection with Trypanosoma spp. in koalas (Phascolarctos cinereus) and their ticks identified using next-generation sequencing (NGS) - Fig 4
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:Characterisation of mixed trypanosome infections in koalas (A), Ixodes holocyclus (B) and Ixodes tasmani (C), based on the number of unique trypanosome species involved. Each doughnut chart shows proportions of the total number (n) of samples harbouring more than one Trypanosoma sp., based on the NGS analysis.
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Phylogenetic characterisation of two novel Anaplasmataceae from Australian Ixodes holocyclus ticks: 'Candidatus Neoehrlichia australis' and 'Candidatus Neoehrlichia arcana'
International journal of systematic and evolutionary microbiology, 2016Co-Authors: Alexander W Gofton, Una Ryan, Stephen L. Doggett, Andrew Ratchford, Peter J IrwinAbstract:Recently, two novel species of Anaplasmataceae were detected in the Australian paralysis tick, Ixodes holocyclus, by 16S rRNA gene metabarcoding. Analysis of these sequences suggested that these novel organisms are closely related to the genus 'Candidatus Neoehrlichia'. In this study, phylogenetic analysis of 16S rRNA (1264 bp), groESL (1047 bp) and gltA (561 bp) gene sequences, and concatenated (2872 bp) sequences, all concur that these novel species belong in the genus 'Candidatus Neoehrlichia' and are most closely related to, but distinct from the only other recognised members of this genus, 'Candidatus Neoehrlichia mikurensis' and 'Candidatus Neoehrlichia lotoris'. Based on their unique molecular signature, we propose to designate these species 'Candidatus Neoehrlichia australis' (reference strain HT41R) and 'Candidatus Neoehrlichia arcana' (reference strain HT94R). Identical 'Candidatus Neoehrlichia australis' 16S rRNA, groESL and gltA sequences were detected in 34/391 (8.7 %) individual Ixodes holocyclus ticks, and sequences were most similar to 'Candidatus Neoehrlichia lotoris' (96.2 %, 83.1 % and 67.2 %, respectively) and 'Candidatus Neoehrlichia mikurensis' (96.2 %, 84 % and 68.4 % respectively). Likewise, identical 'Candidatus Neoehrlichia arcana' 16S rRNA, groESL and gltA sequences were detected in 12/391 (3.1 %) Ixodes holocyclus ticks, and sequences were most similar to 'Candidatus Neoehrlichia lotoris' (98.5 %, 88.7 % and 79.3 %, respectively) and 'Candidatus Neoehrlichia mikurensis' (96.3 %, 84 % and 67.4 % respectively). These new species are the first Anaplasmataceae (except Wolbachia spp.) to be found to be endemic to Australia. The pathogenic consequences of these organisms are yet to be determined.
Peter J Irwin - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetic characterisation of two novel Anaplasmataceae from Australian Ixodes holocyclus ticks: 'Candidatus Neoehrlichia australis' and 'Candidatus Neoehrlichia arcana'
International journal of systematic and evolutionary microbiology, 2016Co-Authors: Alexander W Gofton, Una Ryan, Stephen L. Doggett, Andrew Ratchford, Peter J IrwinAbstract:Recently, two novel species of Anaplasmataceae were detected in the Australian paralysis tick, Ixodes holocyclus, by 16S rRNA gene metabarcoding. Analysis of these sequences suggested that these novel organisms are closely related to the genus 'Candidatus Neoehrlichia'. In this study, phylogenetic analysis of 16S rRNA (1264 bp), groESL (1047 bp) and gltA (561 bp) gene sequences, and concatenated (2872 bp) sequences, all concur that these novel species belong in the genus 'Candidatus Neoehrlichia' and are most closely related to, but distinct from the only other recognised members of this genus, 'Candidatus Neoehrlichia mikurensis' and 'Candidatus Neoehrlichia lotoris'. Based on their unique molecular signature, we propose to designate these species 'Candidatus Neoehrlichia australis' (reference strain HT41R) and 'Candidatus Neoehrlichia arcana' (reference strain HT94R). Identical 'Candidatus Neoehrlichia australis' 16S rRNA, groESL and gltA sequences were detected in 34/391 (8.7 %) individual Ixodes holocyclus ticks, and sequences were most similar to 'Candidatus Neoehrlichia lotoris' (96.2 %, 83.1 % and 67.2 %, respectively) and 'Candidatus Neoehrlichia mikurensis' (96.2 %, 84 % and 68.4 % respectively). Likewise, identical 'Candidatus Neoehrlichia arcana' 16S rRNA, groESL and gltA sequences were detected in 12/391 (3.1 %) Ixodes holocyclus ticks, and sequences were most similar to 'Candidatus Neoehrlichia lotoris' (98.5 %, 88.7 % and 79.3 %, respectively) and 'Candidatus Neoehrlichia mikurensis' (96.3 %, 84 % and 67.4 % respectively). These new species are the first Anaplasmataceae (except Wolbachia spp.) to be found to be endemic to Australia. The pathogenic consequences of these organisms are yet to be determined.
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A survey of ticks (Acari: Ixodidae) of companion animals in Australia.
Parasites & Vectors, 2016Co-Authors: Telleasha L. Greay, Alexander W Gofton, Una Ryan, Charlotte L Oskam, Robert Rees, Peter J IrwinAbstract:Background Ticks are among the most important vectors of pathogens affecting companion animals, and also cause health problems such as tick paralysis, anaemia, dermatitis, and secondary infections. Twenty ixodid species have previously been recorded on dogs, cats, and horses in Australia, including Rhipicephalus sanguineus, Ixodes holocyclus and Haemaphysalis longicornis, which transmit tick-borne diseases. A survey of hard ticks (Acari: Ixodidae) was conducted during 2012–2015 to investigate tick species that infest dogs, cats, and horses in Australia.
Telleasha L. Greay - One of the best experts on this subject based on the ideXlab platform.
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NGS coverage and relative abundance of taxonomically assigned sequence reads obtained from koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:NGS coverage and relative abundance of taxonomically assigned sequence reads obtained from koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
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Comparison of prevalence estimates of Trypanosoma spp. obtained using NGS and Sanger sequencing in koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:Comparison of prevalence estimates of Trypanosoma spp. obtained using NGS and Sanger sequencing in koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
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Prevalence of known genotypes of T. copemani and T. vegrandis in koalas and ticks (Ixodes holocyclus and Ixodes tasmani), determined by NGS at the 18S rRNA locus.
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:Prevalence of known genotypes of T. copemani and T. vegrandis in koalas and ticks (Ixodes holocyclus and Ixodes tasmani), determined by NGS at the 18S rRNA locus.
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Increased genetic diversity and prevalence of co-infection with Trypanosoma spp. in koalas (Phascolarctos cinereus) and their ticks identified using next-generation sequencing (NGS) - Fig 4
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:Characterisation of mixed trypanosome infections in koalas (A), Ixodes holocyclus (B) and Ixodes tasmani (C), based on the number of unique trypanosome species involved. Each doughnut chart shows proportions of the total number (n) of samples harbouring more than one Trypanosoma sp., based on the NGS analysis.
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A survey of ticks (Acari: Ixodidae) of companion animals in Australia.
Parasites & Vectors, 2016Co-Authors: Telleasha L. Greay, Alexander W Gofton, Una Ryan, Charlotte L Oskam, Robert Rees, Peter J IrwinAbstract:Background Ticks are among the most important vectors of pathogens affecting companion animals, and also cause health problems such as tick paralysis, anaemia, dermatitis, and secondary infections. Twenty ixodid species have previously been recorded on dogs, cats, and horses in Australia, including Rhipicephalus sanguineus, Ixodes holocyclus and Haemaphysalis longicornis, which transmit tick-borne diseases. A survey of hard ticks (Acari: Ixodidae) was conducted during 2012–2015 to investigate tick species that infest dogs, cats, and horses in Australia.
Una Ryan - One of the best experts on this subject based on the ideXlab platform.
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NGS coverage and relative abundance of taxonomically assigned sequence reads obtained from koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:NGS coverage and relative abundance of taxonomically assigned sequence reads obtained from koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
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Comparison of prevalence estimates of Trypanosoma spp. obtained using NGS and Sanger sequencing in koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:Comparison of prevalence estimates of Trypanosoma spp. obtained using NGS and Sanger sequencing in koalas and ticks (Ixodes holocyclus and Ixodes tasmani).
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Prevalence of known genotypes of T. copemani and T. vegrandis in koalas and ticks (Ixodes holocyclus and Ixodes tasmani), determined by NGS at the 18S rRNA locus.
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:Prevalence of known genotypes of T. copemani and T. vegrandis in koalas and ticks (Ixodes holocyclus and Ixodes tasmani), determined by NGS at the 18S rRNA locus.
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Increased genetic diversity and prevalence of co-infection with Trypanosoma spp. in koalas (Phascolarctos cinereus) and their ticks identified using next-generation sequencing (NGS) - Fig 4
2017Co-Authors: Amanda D. Barbosa, Telleasha L. Greay, Alexander W Gofton, Andrea Paparini, Annachiara Codello, Amber Gillett, Kristin Warren, Peter Irwin, Una RyanAbstract:Characterisation of mixed trypanosome infections in koalas (A), Ixodes holocyclus (B) and Ixodes tasmani (C), based on the number of unique trypanosome species involved. Each doughnut chart shows proportions of the total number (n) of samples harbouring more than one Trypanosoma sp., based on the NGS analysis.
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Phylogenetic characterisation of two novel Anaplasmataceae from Australian Ixodes holocyclus ticks: 'Candidatus Neoehrlichia australis' and 'Candidatus Neoehrlichia arcana'
International journal of systematic and evolutionary microbiology, 2016Co-Authors: Alexander W Gofton, Una Ryan, Stephen L. Doggett, Andrew Ratchford, Peter J IrwinAbstract:Recently, two novel species of Anaplasmataceae were detected in the Australian paralysis tick, Ixodes holocyclus, by 16S rRNA gene metabarcoding. Analysis of these sequences suggested that these novel organisms are closely related to the genus 'Candidatus Neoehrlichia'. In this study, phylogenetic analysis of 16S rRNA (1264 bp), groESL (1047 bp) and gltA (561 bp) gene sequences, and concatenated (2872 bp) sequences, all concur that these novel species belong in the genus 'Candidatus Neoehrlichia' and are most closely related to, but distinct from the only other recognised members of this genus, 'Candidatus Neoehrlichia mikurensis' and 'Candidatus Neoehrlichia lotoris'. Based on their unique molecular signature, we propose to designate these species 'Candidatus Neoehrlichia australis' (reference strain HT41R) and 'Candidatus Neoehrlichia arcana' (reference strain HT94R). Identical 'Candidatus Neoehrlichia australis' 16S rRNA, groESL and gltA sequences were detected in 34/391 (8.7 %) individual Ixodes holocyclus ticks, and sequences were most similar to 'Candidatus Neoehrlichia lotoris' (96.2 %, 83.1 % and 67.2 %, respectively) and 'Candidatus Neoehrlichia mikurensis' (96.2 %, 84 % and 68.4 % respectively). Likewise, identical 'Candidatus Neoehrlichia arcana' 16S rRNA, groESL and gltA sequences were detected in 12/391 (3.1 %) Ixodes holocyclus ticks, and sequences were most similar to 'Candidatus Neoehrlichia lotoris' (98.5 %, 88.7 % and 79.3 %, respectively) and 'Candidatus Neoehrlichia mikurensis' (96.3 %, 84 % and 67.4 % respectively). These new species are the first Anaplasmataceae (except Wolbachia spp.) to be found to be endemic to Australia. The pathogenic consequences of these organisms are yet to be determined.
