Lyme borreliosis 2 sep 2011 (1.1)

Lyme Borreliosis and Australian Wildlife
FACT SHEET


Introductory statement

Lyme disease is caused by bacteria from the Borrelia spp and is transmitted through ticks
including three host Ixodes ticks11, Haemaphysalis longicornis and some soft-bodied ticks.
Reservoirs for Lyme disease can be many species of mammal, birds and lizards3,8,10. Where it
is endemic in the world, Borrelia spp can cause human disease. Borrelia spp have relatively
little impact on wildlife. Dogs are the only animals apart from humans that are reported to
experience disease7. Ladds (2009) recently reviewed the literature on Borrelia in Australian
native wildlife and concluded that there is no definitive evidence for the existence in Australia
of Borrelia burgdorferi, the causative agent of Lyme disease. Limited testing of Australian
native rats, bandicoots and an agile (brown) antechinus provided no evidence of infection with
borreliae in Australia (Russell et al. 1994; Russell 1995). Despite this, anecdotal reports and
grey literature continue to suggest the presence of this organism in Australia and its presence
in Australian wildlife. Ixodes tick species are present and a number of native wildlife species
are considered to be potential competent reservoir hosts. The situation in wildlife in Australia
is unclear and needs to be clarified.

Aetiology

Lyme disease is caused by the spirochete bacteria Borrelia burgdorferi sensu lato; a species
complex consisting of at least 14 different genomic species11.

Borrelia spp. are transmitted by three host ticks from the Ixodes spp8 and some other species.
The larval and nymph stages of the ticks are fairly non specific in host choice and can infect
many species of mammals, birds and lizards8. Larval and nymphal stages are capable of
picking up Borrelia spp. from their host, and nymphs and adult ticks are capable of
transmission8.
The possibility of a unique Australian genospecies has been postulated16.
Natural hosts
The principle tick vectors are Ixodes ricinus in Europe, Ixodes persulcatus in Eurasia and
parts of Asia and Ixodes pacificus and Ixodes scapularis in North America. None of these
ticks are present in Australia; however, the Ixodes tick Ixodes holocyclus is present. Borrelia
spp. can survive and multiply in many vertebrates which act as reservoirs from which ticks
can take up the bacteria and infect a new host11.
Birds are capable of being infected with Borrelia spp, and while extensive studies into which
birds can and cannot be affected are unavailable, passerines have been investigated as a
potential reservoir3. One study in the Czech Republic showed that Turdus merula, the
Common Blackbird which is a pest species present in Australia, was capable of being a
reservoir for Borrelia spp, some of which are pathogenic to humans3,9. Marine birds have also
been shown to host ticks infected with Borrelia spp. (including pathogenic human species)
and are suspected to be a potential source of introduction4. Ixodes uriae ticks are found on
marine birds in both the southern and northern hemispheres however further work is needed
to unravel the potential transfer of Borrelia spp. between marine and terrestrial species and
the contribution to spread of Lyme disease globally4.
Lizards are also capable of harbouring and transmitting Borrelia spp10. Some Borrelia spp
show a host preference, eg. Borrelia lusitaniae is most commonly associated with lizards10.
Many mammals including rodents act as reservoirs, most notably mice and voles in Europe,
and white tailed deer in North America11.

World distribution
Lyme disease is endemic in North America and Europe12. There have also been isolated
cases reported in Colombia, Mexico and Brazil12. Ladds (2009) cites a personal
communication from R. Junge to W. Hartley (1994) that mentions identification of Borrelia on
DNA probe analysis of growth on tissue culture media, of kidney and urine from an affected
captive kangaroo overseas (p84).

Occurrences in Australia
Ladds (2009) reviewed the literature on Borrelia in Australian native wildlife and concluded
that:
1. There is no definitive evidence for the existence in Australia of Borrelia burgdorferi, the
causative agent of Lyme disease.
2. Limited testing of Australian native rats, bandicoots and an agile (brown) antechinus
provided no evidence of infection with Borreliae in Australia (Russell et al. 1994; Russell
1995).
Despite this, anecdotal reports and grey literature continue to suggest the presence of this
organism in Australia. The situation in wildlife in Australia is unclear and needs to be clarified.

Epidemiology
Borrelia spp are transmitted through tick vectors from the Ixodes family. Three host ticks are
needed for transmission, that is the ticks spend each stage of their two year life cycle on one
host7. In the larval or nymph stage the ticks can pick up Borrelia spp. after biting an infected
host. Once ingested the bacteria infest the ticks’ midgut and remain there until the next stage
in the ticks’ life cycle where they are passed on to a new host1.
Borrelia spp. are transmitted when an infected tick bites a new host in injects the bacteria into
the blood or skin. The bacteria then disseminate from the injection site throughout the body1.
Transmission in dogs has also been reported to occur transplacentally or through blood, urine
or milk7.

Clinical signs
No clinical signs have been associated with infection in wild animals.
Clinical signs are not observed in 95% of infected dogs; however when present, observed
signs consist of transient fever, anorexia and arthritis7. These clinical signs have only been
observed in puppies7.
Clinical signs attributed to Lyme disease in dogs that could not be reproduced experimentally
include renal, cardiac, neurologic or dermatological manifestations7. In particular, renal
disease is suspected to be immune mediated and may associated with co-factors such as the
Borrelia strain or a genetic predisposition7. Further details about Lyme disease in dogs can be
found in the ACVIM Small Animal Consensus Statement on Lyme Disease in Dogs (see
references).
If Lyme disease is present in Australia in people, there is the possibility that it may present differently to the classic signs seen in either Europe or North America2. Diagnosis
Detection of Borrelia spp. can be by culture, cytology or polymerase chain reaction (PCR);
however, this can be difficult, impractical or cost prohibitive7. Dark field microscopy or special
stains such as silver or acridine orange are required to visualise the bacteria7. Borrelia spp. in
vertebrate hosts are usually disseminated and not often found in blood, urine, joint fluid or
CSF7. The organism is more consistently found in connective tissue, synovia, skin or
fibroblasts7.
As the organism can be difficult to isolate, serologic tests for antibodies against Borrelia spp
are preferred to demonstrate that the organism has been present in a vertebrate hosts 7.
Tests that may be performed include enzyme-linked immunosorbent assays (ELISAs),
indirect fluorescent antibody assays (IFAs) and antigen preparations7. When ELISA or IFA is
used7 banding patterns on Western blot immunoassay are needed to differentiate infection
from vaccination.
A new immunohistochemical method called focus floating microscopy (FFM) used in a study
by Eisendle et al. 2007 had improved sensitivity over PCR in tissue sections and may also be
used for histopathological diagnosis5.
In humans, diagnosis is often based on clinical signs as serological evidence has been
inconclusive, thus speculation as to the presence of Lyme disease in Australia continues2.

Pathology
Renal histological lesions suspected to be related to Lyme disease in dogs are immune-mediated glomerulonephritis, diffuse tubular necrosis and regeneration, and lymphocytic-plasmacytic interstitial nephritis7. Laboratory procedures
Whole ticks fixed in 70-90% ethanol are used for PCR and detection of Borellia spp. in
ticks3,4.
Serum collected from mammals, birds and lizards is used for serological diagnosis and tissue
sections fixed in formalin are used for histopathological diagnosis11. Tissue sections are
preferentially taken from skin around a tick bite area, or in dogs, from the organ suspected to
be most affected7.

Treatment
As no disease has been observed in wildlife there are currently no recommendations available for treatment 7. Puppies which have been experimentally infected self cure in 4 days when 6-12 weeks old, and in 1-2 days for 12-26 week old puppies7. In suspected clinical cases tetracycline or amoxicillin are most frequently recommended7. Littman et al. (2006) recommend 10mg/kg of Doxycyclin per os once a day for at least one month for the treatment of dogs7. Prevention and control

A vaccination is available for use in dogs in America and is recommended on a case by case
basis in endemic areas7.

Were Lyme disease to be introduced into Australian wildlife, it would likely not be recognised
until human cases were identified as no known signs of disease are produced in wildlife.
Once established in the host reservoirs control would be difficult in tick endemic areas as
many species may be infected, and infected animals would be difficult to identify.
In America attempts to reduce the incidence of infection transfer from white tailed deer (the
main reservoir host) to humans by reduction in deer numbers reductions were unsuccessful6.

Statistics
The wildlife health network has been collecting information on wildlife health in Australia through its system of state and territory coordinators since 2002. As part of reporting arrangements, wildlife coordinators are asked to report monthly on any interesting or unusual cases in their jurisdictions. Lyme disease and infection with Borrelia spp. is included in this category. These data are collated and stored in the National Wildlife Health Information System (NeWHIS - http://www.wildlifehealth.org.au/AWHN/home.aspx). NOTE: access to this dataset is restricted. If you would like access please contact awhn@zoo.nsw.gov.au. NeWHIS contains no reports of Lyme disease or Borrelia spp. infection in any native or introduced species over this time period. The Australian Registry of Wildlife Health, which maintains a database of detailed pathology records from cases of disease in Australian wildlife also has no records of infection with any species of Borrelia in any species of Australian native animal. The situation regarding Lyme disease in Australia seems unclear. We would welcome definitive reports of infection of Australian wildlife with Borrelia spp. for inclusion in the national dataset. Please contact us with this information at awhn@zoo.nsw.gov.au. Research
The situation in wildlife in Australia is unclear and needs to be clarified. Human health implications

Lyme disease in humans is a common problem in endemic areas and can cause significant
disease11. Sporadic cases of human Lyme disease occur in Australia. However, there is
controversy as to whether the disease was contracted overseas or is present here. One
commentator suggested that in Australia most Lyme Borreliosis sufferers were misdiagnosed
as a more common disease and that evidence is building that Lyme disease is present in
Australia and may be endemic in the Northern beaches of Sydney, Central and North Coast
NSW and Northern Queensland (Akinci pers. comm.). The situation in people, as well as in
wildlife, appears unclear. For definitive information on Lyme Borreliosis in people in Australia
readers should consult their local health care professional.
Conclusions
Lyme disease caused by the spirochete Borrelia spp. and transmitted by Ixodes ticks is
currently considered exotic to Australia. However, this is controversial. Given the presence of
a possible vector (Ixodes holocyclus) and multiple vertebrate reservoirs, it is considered that,
if it is not already here, introduction could lead to establishment of Borrelia spp. in tick
affected areas. As no disease is seen in wildlife it is unlikely that the disease would be
identified until it has become established. This would make control difficult.
Should Lyme disease be introduced to Australia or its presence confirmed, there is likely to be
minimal effect on wildlife. However, the human health implications have the potential to be
significant. The situation in wildlife in Australia is unclear and needs to be clarified.
References and other information

1. Bykowski, T., Woodman, M.E., Cooley, A.E., Brissette, C.A., Wallich, R., Brade, V.,
Kraiczy, P. and Stevenson, B. (2008) Borrelia burgdorferi complement regulator-acquiring
surface proteins (BbCRASPs): Expression patterns during the mammal–tick infection cycle,
International Journal of Medical Microbiology 298(2008) SI, 249-256
2. Cestnick, L. (1998) Lyme disease in Australia, Australia and New Zealand Journal of Public
Health, 22(5): 524
3. Dubska, L., Literak, I., Kocianova, E., Taragelova, V. and Sychra, O. (2009) Differential
Role of Passerine Birds in Distribution of Borrelia Spirochetes, Based on Data from Ticks
Collected from Birds during the Postbreeding Migration Period in Central Europe, Applied and
Environmental Microbiology, 75(3): 596-602

4. Duneau, D., Boulinier, T., Go´mez-Dı´az, E., Peterson, A., Tveraa, T., Barrett, R.T. and
McCoy, K.D. (2008) Prevalence and diversity of Lyme borreliosis bacteria in marine birds,
Infection, Genetics and Evolution 8 (2008) 352–359
5. Eisendle, K, Grabner, T. and Zelger, B. (2007) Focus Floating Microscopy “Gold Standard”
for Cutaneous Borreliosis? American Journal of Clinical Pathology 127:213-222 DOI:
10.1309/3369XXFPEQUNEP5C
6. Jordan, R.A., Schulze, T.L. and Jahn, M.B. (2007) Effects of Reduced Deer Density on the
Abundance of Ixodes scapularis (Acari: Ixodidae) and Lyme Disease Incidence in a Northern
New Jersey Endemic Area, Journal of Medical Entomology 44(5): 752-757

7. Littman MP, Goldstein RE, Labato MA, Lappin, M.R. and Moore, G.E. (2006) ACVIM Small
Animal Consensus Statement on Lyme Disease in Dogs: Diagnosis, Treatment, and
Prevention, Journal of Veterinary Internal Medicine 20(2):422-434
8. Ostfeld, R.S., Canham, C.D., Oggenfuss, K., Winchcombe, R.J. and Keesing, F. (2006)
Climate, Deer, Rodents and Acorns as Determinants of Variation in Lyme-Disease Risk,
PLoS Biology (4)6: 1058-1068
9. Queensland Government DPI (2007) Common Blackbird Warning, Queensland
Government Deparment of Primary Industries and Fisheries at http://www.dpi.qld.
gov.au/documents/Biosecurity_EnvironmentalPests/IPA-Common-Blackbird-Warning.pdf
Accessed 2/8/2010
10. Richter, D. and Matuschka, F.R. (2006) Perpetuation of the Lyme Disease Spirochete
Borrelia lusitaniae by Lizards, Applied and Environmental Microbiology, 72(7) 4627-4632
11. Stanek, G. and Strle, F. (2003) Lyme borreliosis, Lancet 362: 1639-1647.
12. Talhari, A., De Souza Santos M.N., Talhari, C., De Lima Ferreira, L.C., Silvam M.R. Jr.,
Zelger, B.,Massone, C., Ribeiro-Rodrigues R. (2010) Borrelia Burgdorferi “sensu lato” in
Brazil: Occurrence confirmed by immunohistochemistry and focus floating microscopy, Acta
Tropica 115(2010) 200-204.
13. Ladds PW (2009) Pathology of Australian native wildlife. CSIRO Publishing, Collingwood,
VIC Australia.
14. Russell RC (1995) Lyme disease in Australia - still to be proven. Emerging Infectious
Diseases 1, 29 - 31.
15. Russell RC, Doggett SL, Munro R, Ellis J, Avery D, Hunt C and Dickerson D (1994) Lyme
disease: a search for a causative agent in ticks in south-eastern Australia. Epidemiology and
Infection 112, 375 - 384.
16. Wills, M. 1995. Lyme Borreliosis, The Australian Perspective. PhD thesis. University of
Newcastle.
Acknowledgements
We are grateful to the many people who had input into this fact sheet. Special thanks to
Mualla Akinci and the Karl McManus Foundation (www.karlmcmanusfoundation.org.au).
Updated: 18 August 2011

To provide feedback on this fact sheet

The Australian Wildlife Health Network would be very grateful for any feedback on this fact
sheet. This is important in the case of Borrelia sp in wildlife in Australia because of the
possible human health implications and the apparent lack of consensus on its presence.
Please provide detailed comments or suggestions to rwoods@zoo.nsw.gov.au. (A Word
version is available to make Track Changes if it is easier – contact us at
rwoods@zoo.nsw.gov.au). We would also like to hear from you if you have a particular area
of expertise and would like to produce a fact sheet (or sheets) for the network (or update
current sheets). A small amount of funding is available to facilitate this. We are especially
keen to hear from PhD students who might be able to contribute, or are working in the area.

Disclaimer
This fact sheet is managed by the Australian Wildlife Health Network for information purposes
only. Information contained in it is drawn from a variety of sources external to the Australian
Wildlife Health Network. Although reasonable care was taken in its preparation, the
Australian Wildlife Health Network does not guarantee or warrant the accuracy, reliability,
completeness, or currency of the information or its usefulness in achieving any purpose. To
the fullest extent permitted by law, the Australian Wildlife Health Network will not be liable for
any loss, damage, cost or expense incurred in or arising by reason of any person relying on
information in this fact sheet. Persons should accordingly make and rely on their own
assessments and enquiries to verify the accuracy of the information provided.

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