CURRENT RESEARCH ON TICK PARALYSIS

National Tick Paralysis Forums
Tick Vaccine Research
Biology of Ixodes holocyclus and Ixodescornuatus
Population genetics of Ixodes holocyclus
Tick antiserum dose/response study
Blood gases in tick paralysis
ELISA assay to measure protective level of anti-toxinincanine antiserum
Measurement of myocardial function in tickpoisoning
Serological survey for Lyme Disease of dogs in the Northern Beaches area of Sydney
Measurement of cardiopulmonary effects using Swann-Ganz catheters (2002-3)
Toxins of Paralysis Ticks (2003)
Hypothermia and Respiratory Problems in tick paralysis (2003)
ELISA parasitology (2003)
Tick Antiserum reactions (2003)
Clinical cases - QT (2003)
Therapy choices (2003)

 

National Tick Paralysis Forums

1st National Tick Paralysis Forum

A National Tick Paralysis Forum has been held with the supportof Merial Australia Pty Ltd, and is being co-ordinated byElizabeth Court (BVSc MACVSc MVetClinStud, Veterinary TechnicalServices, Merial Australia). A survey of participating veterinary practices is to commence in September 1998. The survey has beenwritten and approved by the National Tick Paralysis Forum which met for the first time in May this year (1998). Key veterinariansand scientists met at the Forum to discuss methods of controllingtick poisoning, and towork out ways of distributing thisinformation to veterinarians. A detailedprospectivequestionnaire was determined to be a sound method for collectinginformation with the objective of publishing the results in anAustralianScientific Journal.

2nd National Tick Paralysis Forum

Update- Mar 2000. The 2nd Forum was held Feb 28-2000. The findings of the prospective national tick paralysissurvey were discussed.Some questions were answered, some myths apparently debunked and new questions were raised. The resultsand discussion will be submitted for publication.Major issuesincluded: what dose of antiserum?, what dose (if any) of acepromazine?, how do we manage pulmonary oedema?, how do we manage oesophageal dysfunction?,how important is ventilatory support? New research concerning the effectsof tick poisoning on myocardial contractility was presented by Dr Fiona Campbell(Univof Qld).

Vaccine Research

For the latest developments in the production of a vaccineagainst thetick toxin(s) see the University of Technology Sydneysite at UTS- tick vaccine. The research isbeing led by Associate Professor Kevin Broady, of theImmunobiology Unit in the Department of Cell andMolecularBiology.

Update- July 99. A recombinant form of the toxin thatwas not toxic but originally appeared in experiments using miceto be highly immunogenic and protective did not show the sameparalysis-protection in dogs, although it was still highlyimmunogenic. Overall, this would seem to indicate that theoriginal recombinant toxin used was not in the correctconformational state (ie. not properly "folded") toinduce protective antibodies. The toxin gene needs to beexpressed in a different way. Further funding is required tocontinue this useful research. It looks like a viable vaccine isstill some years away. (paraphrased from email by Prof KevinBroady, courtesy Peter Griswold).

Update- Jan 2000. The tick paralysis vaccine project,while it addresses an important Australian problem, has not beenable to attract any public or government research funding andonly a small amount of commercial funding. So to date thisresearch has been performed by postgraduate students as research projects. Because the project is now at such an advanced stageProf KevinBroady may instigate a university-based company to develop the vaccine thisyear (2000) with the aim of having aproduction available for the 2001 tickseason. (paraphrased fromemail by Kevin Broady, courtesy Sally-Ann Edwards).

Update- June 2000. Very recently an MSc student hasexpressed the toxin in a different system and shown therecombinant toxin reacts with the antibodies in the commercialanti-tick serum. This suggests that the folding problem has beenovercome. Further testing with this product is underway.Theproject is in a good position but there is always more work to dobeforea vaccinecan be released to the public. (paraphrased fromemail by KevinBroady, courtesy Brian Pickering of Dog-E-Data )

Update- Oct 2000. Ticks are being sought to carry outclinical trials necessary before the vaccine can be released tothe public. There are still many unanswered questions about thefunction and structure of the neurotoxin which need to be workedout to permit future improvement of the vaccine. Contact detailsare Matt Padula (BSc, PhD student, Tick Research Unit, UTS, Matthew.padula@uts.edu.auand Assoc Prof Kevin Broady, Head, Tick Research Group, Dept ofCell and Molecular Biology, University of Technology, Sydney, Westbourne St, Gore Hill, Sydney NSW 2065, tel 02 9514 4101 , fax02 95144026, Kevin.broady@uts.edu.au.

The biology of the Australian paralysistick

Biology of Ixodes holocyclus and the related species, Ixodes cornuatus. PhD thesis by Jackson J - University of Melbourne.

Abstract

An electrophoretic comparison of the Australian paralysis tick, Ixodes holocyclus Neumann, 1899, with I. cornuatus Roberts, 1960 (Acari : Ixodidae) Janey Jackson (AC) , Neil B. Chilton (A) , Ian Beveridge(A) , Michelle Morris (B) and Ross H. Andrews (A) Department of Veterinary Science, UniversityofMelbourne, 250 Princes Highway, Werribee, Vic. 3030, Australia.
(B) Department of Microbiology and Immunology, University of Adelaide, GPO Box 498, Adelaide, SA 5000, Australia.

(C) To whom correspondence should be addressed. email: j.jackson@vet.unimelb.edu.au. Abstract: An electrophoretic study was conducted on ticks morphologically identified as either Ixodes cornuatus or I. holocyclus from Tasmania and several localities on mainland Australia. Ticks were characterised genetically at 27 enzyme loci encoding 24 enzymes. The extent of genetic divergence (52-69% fixed differences) between ticks from Tasmania and those from the mainland was equivalent to that found between these two groups and two morphologically distinct species, I. hirsti and I. fecialis. The Tasmanian tickstherefore represent a different species from the specimens from the mainlandandthe electrophoretic data show that the morphological characters currentlyused to distinguish I. holocyclus from I. cornuatus are inadequate. Genetic heterogeneity was detected in samples from differentlocalities on the mainland. This could represent either population variation,or the existence of cryptic species, but more ticks from these mainland localities need to be examined electrophoretically to resolve this. Australian Journal of Zoology, 1998, 46, 109–117 ©CSIRO 1998 0004-959X/98/020109 Australian Journal of Zoology: www.publish.csiro.au/journals/ajzPublished by CSIRO PUBLISHING for CSIRO and the Australian Academy ofScience Enquiries: The Managing Editor, Australian Journal of Zoology,CSIROPUBLISHING, PO Box 1139 (150 Oxford Street), Collingwood, Vic. 3066,Australia.Telephone +61 3 9662 7622; fax +61 3 9662 7611; email david.morton@publish.csiro.au

Population Genetics

Population genetics of the Australian Paralysis Tick Ixodesholocyclus (honours project). Matthew Shaw. BSc at theUniversity of Queensland. Honours at the University of Queensland. It has been suggested by some workers that there are differentforms of this species. This suggestion has not been tested usinggenetic data. The aim of this project is to survey populationsalongthe Eastern seaboard of Australia, assessing the level ofinterpopulationvariability in ribosomal DNA. Various regions arebeing amplified, currentlythe D1 of28S rRNA, ITS1 and ITS2.Once enough regions have been amplifiedwith PCR andsequenced,then phylogenies can be constructed in order to testfor theexistanceof distinct regional forms. It is intended to use Ixodescornuatusas an outgroup for this analysis.

Anti-tick serum dose-response study

A tick antiserum dose/response study by Coralie Endean. Aveterinarian working in the Animal Emergency Center in Brisbaneis doing (in 1998) a 2year retrospective study using threeparameters- staging, dose and outcometo try to work out a dose/survivalcurve. Email CoralieEndean .

Blood gases in tick paralysis

Blood gases in tick paralysis- current masters researchproject by Chris Jensen, veterinary surgeon practicing in TheGap, Brisbane. Email ChrisJensen.

Anti-toxin activity in commercial sera

Developing an ELISA assay to measure the anti-toxin activityof the dog serum used to treat paralysed animals. By Rogan Lee,Department of Parasitology The University of Queensland,Brisbane, 4072. Australia. Tel: 07-33652572Fax: 07-33651588,Email RoganLee

Measurement of myocardial function in tick poisoning (2002)

Fiona Campbell (University of Queensland) has undertakenmeasurements of myocardial function before, during and aftertreatment for tick paralysis. Parameters included thoracic X-Rays,ultrasound, ECG, PCV, and assays of cortisol and adrenaline. Thisresearch has so far found evidence of myocardial depression, pulmonary oedema and rising PCV. Systemic hypertension was found not to be a major problem. Respiratory distress was found to berelated more to pulmonary oedema and muscular fatigue than tocentral respiratory depression. Dr Rick Atwell believes thattreatment for left-sided heart failure should be considered inall tick cases- eg using vasodilators and diuretics andsupplemental oxygen (when it can be delivered in a stress freemanner). [information from article in The Veterinarian,Dec-Jan, 2000; by Jonica Newby]

Serological survey for Lyme Disease of dogs in the Northern Beaches area of Sydney (2002)

Kirsten Ingwersen, student in Veterinary Microbiology at theUniversity of Sydney, is also involved with Lyme Disease investigation at the Microbiology Dept at Royal North Shore Hosp,Sydney. Dr Henry Collins of the University of Sydney is also involved with this study.

Measurement of cardiopulmonary effects using Swann-Ganz catheters etc (2002-3)

Ben Davidson. Veterinary Specialist Centre, Sydney. Using Swann-Ganz and arterial catheters to measure blood pressure, blood gases, pre-capillary wedge pressures on naturally occurring cases of tick paralysis.

Toxins of Paralysis Ticks (2003)

Natalie Steen. Presentation at Australian College of Veterinary Scientists, Scientific Meeting, July 2003.

Hypothermia and Respiratory Problems in tick paralysis (2003)

Anna Fearnley. Presentation at Australian College of Veterinary Scientists, Scientific Meeting, July 2003.

 

ELISA Parasitology (2003)

Sonja Hall. ELISA Parasitology (Tick Paralysis Research Group, 2003).

Tick Antiserum Reactions (2003)

Daniel Schull. Tick Antiserum reactions. (Tick Paralysis Research Group, 2003).

Clinical Cases -QT (2003)

Sarah Toole. Clinical Cases - QT (Tick Paralysis Research Group, 2003).

Therapy Choices (2003)

Trish Clark. Therapy Choices (Tick Paralysis Research Group, 2003).

 

 

The Paralysis Tick of Australia - Home

E-mail Us to report a broken link!

 

Main Categories