Lyme Disease in Australia

What is Lyme Disease?

The causative agent of Lyme disease is the bacterium Borrelia burgdorferi sensu lato. B. burgdorferi infects animals such as deer, rodents and birds. Hard-bodied ticks of the Ixodes genus feed on the infected animals. If a tick then bites a human, the B. burgdorferi bacteria may transfer to the human host, causing Lyme disease. Symptoms of Lyme disease include a circular red rash, fever, arthritic joint pain, and cognitive dysfunction.

For more information about Lyme disease, please read “Lyme Disease (Borreliosis): Symptoms and Treatment“.

Common vectors for Lyme disease include the deer tick in North America, and the sheep tick in Europe. Although Lyme disease is currently prevalent in most parts of the world, debate continues as to whether or not it exists in Australia.

Lyme disease is easily misdiagnosed. Known as the “great mimic”, Lyme disease causes symptoms resembling those of influenza, fibromyalgia, lupus, multiple sclerosis, chronic arthritis or other health conditions. Conversely, other infectious tick-borne diseases in Australia and throughout the world can manifest symptoms similar to those of Lyme disease, but serology testing for Lyme disease will return a negative result.

Research into the incidence of Lyme disease in Australia is limited, due to the lack of confirmed cases of the disease. Awareness of Lyme disease continues to grow, leading some to believe that Lyme disease could be the cause of previously unexplained medical symptoms.

Historical Incidence of Lyme Disease in Australia

According to the Department of Medical Entomology at Sydney University, an outbreak of suspected Lyme disease occurred in the Hunter Valley region of New South Wales in 1982. Six people manifested symptoms similar to those of Lyme disease. Serology testing indicated the possible presence of B. burgdorferi antibodies in the blood. Later tests failed to confirm this diagnosis.

In 1986, reports of erythema migrans, a circular red rash characteristic of the disease, came from the south and central coasts of New South Wales. Patients also reported fever. None of these cases tested positive for Lyme disease.

From 1986 to 1989, in Queensland, the State Health Laboratories tested 1,247 patients for B. burgdorferi antibodies using indirect fluorescent antibody technique (IFAT). Fifteen percent of patients (186 people) tested positive. By itself, IFAT is not a reliable procedure. Due to non-standardized testing guidelines, and cross-contamination by other bacteria, false positives are common. Medical personnel did no further testing to confirm a Lyme disease diagnosis.