Dataset Information

Evidence for Ixodes holocyclus (Acarina: Ixodidae) as a vector for human lyme Borreliosis infection in Australia.

ABSTRACT: Ixodes holocyclus (Acarina: Ixodidae) and Ixodes cornuatus (Acarina: Ixodidae) are two tick species found in the more densely populated areas of Australia and are known to be the cause of the neurotoxic disease tick paralysis in humans and mammals. Borreliosis otherwise known as Lyme disease is an emerging infectious disease in humans in Australia. Borrelia burgdorferi sensu stricto (Spirochaetales: Spirochaetaceae) and sensu lato are closely related spirochetal species that are the causative agents of Lyme disease in humans. Clinical transmission of this tick-borne disease can be identified in several but not all cases by a characteristic rash known as erythema migrans. However, there has been no study of the tick vectors of this infection in Australia. We used morphological and molecular techniques to identify unequivocally the ticks on the patients of this study to be I. holocyclus and then show the presence of B. burgdorferi sensu stricto infection in erythema migrans biopsies. I. holocyclus has not previously been associated with erythema migrans or Lyme disease. Two patients presented to the lead author's medical practice with erythema migrans in mid and late 2012. The morphology and cytochrome oxidase 1 and ITS2 genes of the two ticks were studied. The skin at the attachment site was sampled by central biopsy for both real time and endpoint Borrelia polymerase chain reaction (PCR) analysis and subsequent sequencing. Morphologically, the two ticks were either I. holocyclus or I. cornuatus. Molecular studies and nucleotide sequencing revealed that both ticks were I. holocyclus. Real time and endpoint PCR on the central tissue biopsy samples returned positive results for B. burgdorferi DNA. Our results are evidence for transmission of B. burgdorferi sensu stricto species to humans by the tick I. holocyclus in Australia. I. holocyclus is commonly associated with human tick bites on virtually the entire eastern coastline of Australia.

SUBMITTER: Mayne P

PROVIDER: S-EPMC5657863 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Evidence for Ixodes holocyclus (Acarina: Ixodidae) as a vector for human lyme Borreliosis infection in Australia.

Mayne P P Song S S Shao R R Burke J J Wang Y Y Roberts T T

Journal of insect science (Online) 20140101

Ixodes holocyclus (Acarina: Ixodidae) and Ixodes cornuatus (Acarina: Ixodidae) are two tick species found in the more densely populated areas of Australia and are known to be the cause of the neurotoxic disease tick paralysis in humans and mammals. Borreliosis otherwise known as Lyme disease is an emerging infectious disease in humans in Australia. Borrelia burgdorferi sensu stricto (Spirochaetales: Spirochaetaceae) and sensu lato are closely related spirochetal species that are the causative ag ...[more]

PMID: 25434042

Similar Datasets

Project description:Mixed or multiple-strain infections are common in vector-borne diseases and have important implications for the epidemiology of these pathogens. Previous studies have mainly focused on interactions between pathogen strains in the vertebrate host, but little is known about what happens in the arthropod vector. Borrelia afzelii and Borrelia garinii are two species of spirochete bacteria that cause Lyme borreliosis in Europe and that share a tick vector, Ixodes ricinus Each of these two tick-borne pathogens consists of multiple strains that are often differentiated using the highly polymorphic ospC gene. For each Borrelia species, we studied the frequencies and abundances of the ospC strains in a wild population of I. ricinus ticks that had been sampled from the same field site over a period of 3 years. We used quantitative PCR (qPCR) and 454 sequencing to estimate the spirochete load and the strain diversity within each tick. For B. afzelii, there was a negative relationship between the two most common ospC strains, suggesting the presence of competitive interactions in the vertebrate host and possibly the tick vector. The flat relationship between total spirochete abundance and strain richness in the nymphal tick indicates that the mean abundance per strain decreases as the number of strains in the tick increases. Strains with the highest spirochete load in the nymphal tick were the most common strains in the tick population. The spirochete abundance in the nymphal tick appears to be an important life history trait that explains why some strains are more common than others in nature. Lyme borreliosis is the most common vector-borne disease in the Northern Hemisphere and is caused by spirochete bacteria that belong to the Borrelia burgdorferi sensu lato species complex. These tick-borne pathogens are transmitted among vertebrate hosts by hard ticks of the genus Ixodes Each Borrelia species can be further subdivided into genetically distinct strains. Multiple-strain infections are common in both the vertebrate host and the tick vector and can result in competitive interactions. To date, few studies on multiple-strain vector-borne pathogens have investigated patterns of cooccurrence and abundance in the arthropod vector. We demonstrate that the abundance of a given strain in the tick vector is negatively affected by the presence of coinfecting strains. In addition, our study suggests that the spirochete abundance in the tick is an important life history trait that can explain why some strains are more common in nature than others.

Project description:BACKGROUND: Borrelia burgdorferi, the causative agent of Lyme disease (LD), and Babesia, Bartonella, and Ehrlichia species (spp.) are recognized tick-borne pathogens in humans worldwide. Using serology and molecular testing, the incidence of these pathogens was investigated in symptomatic patients from Australia. METHODS: Sera were analyzed by an immunofluorescent antibody assay (IFA) followed by immunoglobulin (Ig)G and IgM Western blot (WB) assays. Both whole blood and sera were analyzed for detection of specific Borrelia spp. DNA using multiplex polymerase chain reaction (PCR) testing. Simultaneously, patients were tested for Babesia microti, Babesia duncani, Anaplasma phagocytophilum, Ehrlichia chaffeensis, and Bartonella henselae infection by IgG and IgM IFA serology, PCR, and fluorescent in situ hybridization (FISH). RESULTS: Most patients reported symptom onset in Australia without recent overseas travel. 28 of 51 (55%) tested positive for LD. Of 41 patients tested for tick-borne coinfections, 13 (32%) were positive for Babesia spp. and nine (22%) were positive for Bartonella spp. Twenty-five patients were tested for Ehrlichia spp. and (16%) were positive for Anaplasma phagocytophilum while none were positive for Ehrlichia chaffeensis. Among the 51 patients tested for LD, 21 (41%) had evidence of more than one tick-borne infection. Positive tests for LD, Babesia duncani, Babesia microti, and Bartonella henselae were demonstrated in an individual who had never left the state of Queensland. Positive testing for these pathogens was found in three others whose movements were restricted to the east coast of Australia. CONCLUSION: The study identified a much larger tick-borne disease (TBD) burden within the Australian community than hitherto reported. In particular, the first cases of endemic human Babesia and Bartonella disease in Australia with coexisting Borrelia infection are described, thus defining current hidden and unrecognized components of TBD and demonstrating local acquisition in patients who have never been abroad.

Dataset Information

Evidence for Ixodes holocyclus (Acarina: Ixodidae) as a vector for human lyme Borreliosis infection in Australia.

Publications

Evidence for Ixodes holocyclus (Acarina: Ixodidae) as a vector for human lyme Borreliosis infection in Australia.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets