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LYME DISEASE IN AUSTRALIA? Mualla McManus B.Pharm Ph.D AACP,

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Presentation on theme: "LYME DISEASE IN AUSTRALIA? Mualla McManus B.Pharm Ph.D AACP,"— Presentation transcript:

1 LYME DISEASE IN AUSTRALIA? Mualla McManus B.Pharm Ph.D AACP,

2 Possible Sources of Borrelia in Australia  Imported animal species cattle, sheep, rabbit, deer, fox, rats, mice imported during the last 2 centuries from Europe proven reservoirs of Borrelia.  Migratory birds Nest or visit Australia carry ticks with Borrelia and co-pathogens  Australia has it own unique species

3 B. burgdorferi imported into Australia?  1872- 12 tick infested Brahmin cattle were brought to Darwin from Java Indonesia  Babesiosis and anaplasmosis spread throughout the cattle country Kimberley to Northern NSW  Mulhearn (1946) isolated B. theileri from cattle tick ( Boophilus microplus )  Migratory birds that nest along the seaboard and in the wetlands

4 East-Asian Australasian Flyway- Bird migration

5 Australian Indigenous Borrelia  Shaw (1800) saw spirochetes in great grey kangaroo  Desmarest (1822)- red kangaroo  Mackeras (1959) identified Borrelia spirochetes from bandicoots, kangaroos, wallabies  Carley and Pope (1962)- isolated Borrelia spirochetes from native rats and characterised a new species – B. queenslandica  Borrelia queenslandica -fastidious growth 2 weeks in vitro and 2 weeks in in vivo. Caused relapsing infection in lab mice

6 Common Ticks in Australia

7 Male Female Tick 3 Host Life Cycle eg Ixodes holocyclus Engorged female tick lays eggs on ground (approx 3000) then dies Adult tick seeks 3 rd host, a large mammal including humans, engorges with blood, mates & drops off host. Larvae seek 1 st host, a small mammal such as a bandicoot, feed & drop off host Engorged larva shelters in grass & moults to nymph Nymph seeks 2 nd host, small to medium mammal feeds & drops off Engorged nymph shelters in grass & moults into adult, male and female Larva are the size of a pinhead & have 6 legs Nymphs are the size of a matchhead & have 8 legs Engorged adults can be the size of a pea & have 8 legs Warm, moist conditions allow eggs to hatch within 7-9 weeks into larvae

8 Borrelia in Australian ticks  Paralysis tick: ( Ixodes holocyclus )- indigenous tick  Brown dog tick- ( Rhipicephalus sanguines )- not indigenous, common in warm climates. Shown to harbour Borrelia  Bush tick ( Haemaphysalis longicornus )- imported from Japan 1902. Shown to harbour Borrelia, Anaplasma, Ehrlichia (Meng et al 2008, Mi-Jin&Joon, 2010)

9 Distribution of Borrelia

10 Clinical Cases of Lyme Disease  Stewart et al 1982- First clinical case of Lyme Disease- erythema migrans rash and arthritis in Hunter valley  Lawrence et al 1986 Central Coast  McCrossin, 1986- South Coast  QLD State Health- 1986-1989- 15% ELISA and IFA  Hudson et al 2003- 10 skin biopsies- +ve Borrelia.  Recently Mayne 2012- skin biopsies- +ve for Borrelia

11 NHMRC Funded study  Russell et al (1994)- study  Unable to isolate Borrelia burgdorferi sensu lato from Australian ticks  They were looking for B. burgdorferi sensu stricto (American strain)  PCR products not Borrelia, SLO- aggregates of bacterial flagella  Conclusion: No definite evidence of Borrelia or any other TB spirochetes that may cause Lyme disease in Australia

12 Uni. of Newcastle group  Uni. of Newcastle group- Prof Richard Barry’s group  Cultured spirochetes from fed ticks collected from the North of Sydney to Mid North Coast  Isolated spirochetes who had fastidious growth requirements and died after 2 weeks in culture  PCR products which had sequence homology to B.burgdorferi and variation in DNA sequence suggesting the presence of unique Australian genospecies. (Wills 1995)

13 Conclusion  Given that Mackerras (1959), Carley and Pope (1962) and Wills and Barry (1995) managed to isolate, grow and identify Borrelia in Australia, scientific evidence supports the existence of Borrelia in Australian ticks, rather then the absence.  Both imported and indigenous Borrelia is highly likely to be present in Australia

14 Borrelia In Australia  Indigenous Borrelia genospecies in Australia- very high probability.  Other imported Borrelia strains highly likely  B.garinii, B.afzelii, B.burgdorferi and others imported by travellers- people and birds  Very high probability

15 Borrelia microbiology  Spirochete  21 plasmids - fast evolving protozoa like bacteria, genomic flux  Can exist in 3 different forms- spirochete, cell wall deficient and dormant cyst, intra and extracellular  Slow replication time in vivo and in vitro (12- 18hrs).  Release exo and endo toxins-Jarisch Herxheimer’s reaction

16 Diagnosis  Clinical – familiarity with clinical signs and symptoms  Patients with baffling set of symptoms consider Lyme  Path lab tests supplement the diagnosis.  Tests should not be used as the sole method of diagnosis

17 Diagnostics  Testing in Australia  2 Tier- ELISA then Western Blot  ELISA- recombinant Borrelia proteins embedded in a matrix bind to antibodies from the patient  Western Blot (Immunoblot)- proteins separated electrophoretically that bind antibodies

18 Australian Criteria: based on CDC Surveillance Criteria  Positive ELISA  Western Blot ( WB)  IgM WB- Greater than 2 bands = Positive within 6 weeks of a tick bite  IgG WB 5 bands from ( 10 bands)- (18,22,25,28,30,39,41,45,58,66, 99KDa)  No correlation with clinical symptoms

19 LYME DISEASE TESTING  ELISA, WB- Serology based tests  PCR- Bacterial DNA detection- Non Serology test, highly sensitive narrow specificity.  ELISPOT- T cell stimulation- T cell immunity  Culture- in vitro culture biopsy

20 Why ELISA is not the right test for Borrelia infection  Only one, or more recombinant Borrelia antigens in the matrix  Complex immunosuppression induced by Borrelia decreases the sensitivity of the test  The situation where patients are deficient in IgG or IgM will never get a positive= False negative

21 ILADS versus IDSA  ILADS- International Lyme and Associated Diseases Society  Treat with antibiotics till patient is better.  IDSA- Infectious Diseases Society America  Treat acute Lyme disease- 28 days of antibiotics if still have symptoms  Post- Lyme syndrome. Psychosomatic disease  No such thing as Chronic Lyme

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23  Growing number of people have the symptoms of Lyme disease, some have never travelled outside Australia and many have confirmatory results from overseas labs.  Australian testing needs to redesigned to suit the Australian situation. Lyme Disease in Australia

24 Summary  Lyme Disease and Co-infections in Australia- A state of Immune dysregulation  Immune system needs to be supported  Diagnostic results should be interpreted accordingly the diagnostics based upon serology assume a competent immune system, a negative result may not be a real negative  The immune status of the patient needs to be assessed before diagnosis and during treatment  Ig levels, and lymphocyte markers, Vit D125OH


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