Lyme Disease in Australia

lyme disease australia tick ixodes holocyclus

Could the Ixodes holocyclus, Australian paralysis tick also be a carrier for Lyme disease bacteria?

The current thinking on Lyme disease in Australia is that only a few tick species are capable of carrying the Borrelia bacteria and, as such, these few ticks are the only ones capable of spreading the infection to humans and other animals. Those ticks identified as carriers are present in Asia, Europe, and North America but are not thought to have populated Australia. The last survey on ticks to be carried out in Australia was in the 1990s, however, where some 12,000 ticks were collected in New South Wales and tested for Borrelia; none were found to be infected. A particular specied of paralysis tick, Ixodes holocyclus can cause tick paralysis, tick typhus and allergic reactions and authorities have admitted that Australian ticks may cause an infection similar to Lyme disease but which is, so far, unable to be characterized.

Australian Lyme Disease Research

Research dating back to the 1960s did identify an Australian strain of Borrelia, Borrelia queenslandica, but more recent research into Lyme disease in Australia found no evidence of the presence of Borrelia in ticks. This research by Russell, et al, in 1994 has been criticized for flawed methodology and it appears that little follow-up has occurred into B. queenslandica in the past fifty years, meaning that those testing for Lyme disease infection are unlikely to test against this strain, particularly if overseas laboratories are used. This is exemplified by the paper published in 1991 by Piesman and Stone who tested the ability of the Australian paralysis tick (Ixodes holocyclus) to act as a carrier of Borrelia. Their tests concluded that larval ticks did ingest the bacteria but did not become infected. Importantly, thier research used only the North American strain of Borrelia, B. burgdorferi and the scientists concluded that their experiments should be repeated with Australian strains of spirochaetes, research which does not appear to have been carried out.

Diagnosing Lyme Disease in Australia

One case report of a patient with Lyme borreliosis found that a skin biopsy tested positive for Borrelia garinii (a strain of Lyme disease bacteria found predominantly in Europe and Asia), despite the patient having negative serological test results. The patient in question had suffered with symptoms of Lyme disease for two years and the researchers concluded that the infection may have been acquired in Australia despite travel to Europe some seventeen months prior to illness onset. Worryingly, the patient had had repeated doses of antibiotics but the infection persisted, potentially demonstrating the need for longer antibiotic treatment for infection or possibly showing that the infection was recent and coincedental in regards to prior symptoms that remain unexplained.


ILADS Research in Australia

A paper published in the International Journal of General Medicine last year reported confirmation of Lyme disease infection according to IFA and Western Blot in 55% of patients with reported Lyme disease symptoms who had not travelled overseas recently. Of the fifty-one patients tested for Lyme disease, 41% had evidence of more than one tick-borne infection, including one patient who had never left Queensland but who tested positive for Borrelia, Babesia, and Bartonella. Three others who had not travelled farther than Australia’s east coast also tested positive for these pathogens. The research was carried out by the International Lyme and Associated Diseases Society (ILADS) who continually rail against Lyme denial from governments, local authorities, and orthodox medical associations. The research by Mayne (2011) used polymerase chain reaction (PCR) testing to assess the presence of Borrelia subspecies DNA, as well as looking for evidence of infection with Babesia microti, Babesia duncani, Anaplasma phagocytophilum, Ehrlichia chaffeensis, and Bartonella henselae. Forty-one patients with symptoms of tick-borne infections were tested; 32% had positive results for Babesia spp., 22% were positive for Bartonella spp., and of the twenty-five patients tested for Ehrlichia spp. 16% were positive for Anaplasma phagocytophilum (none tested postiive for Ehrlichi chaffeensis).

Recognizing Lyme Disease in Australia

Ticks in Australia tend to be most active in late spring, summer, and in early autumn and those engaging in outdoor activities such as hiking, biking, or even gardening or trail-building in forested or densely vegetated areas should become familiar with tick-control methods so as to reduce potential exposure. Doctors and other healthcare professionals need to become more aware of the potential manifestations of Lyme disease, especially given that symptoms of progressive or incurable diseases such as dementia, multiple sclerosis, and schizophrenia can be a result of neuroborreliosis, making them treatable rather than simply manageable with medications. There may be no official recognition of the presence of Lyme disease in Australia but pressure is mounting and a reassessment is, hopefully, only a matter of time.

References


Russell RC, Doggett SL, Munro R, Ellis J, Avery D, Hunt C, Dickeson D., Lyme disease: a search for a causative agent in ticks in south-eastern Australia. Epidemiol Infect. 1994 Apr;112(2):375-84.

Mayne PJ., Emerging incidence of Lyme borreliosis, babesiosis, bartonellosis, and granulocytic ehrlichiosis in Australia. Int J Gen Med. 2011;4:845-52. Epub 2011 Dec 16.

Hudson BJ, Stewart M, Lennox VA, Fukunaga M, Yabuki M, Macorison H, Kitchener-Smith J., Culture-positive Lyme borreliosis. Med J Aust. 1998 May 18;168(10):500-2.

Almeida OP, Lautenschlager NT., Dementia associated with infectious diseases. Int Psychogeriatr. 2005;17 Suppl 1:S65-77.

Piesman J, Stone BF., Vector competence of the Australian paralysis tick, Ixodes holocyclus, for the Lyme disease spirochete Borrelia burgdorferi. Int J Parasitol. 1991 Feb;21(1):109-11.