RESEARCH PAPER: Lyme Disease / Borreliosis: An Overview of Lyme and Direction for further Research required in Australia
ISBN: 978-0-646-90428-3
Researched & Written by Karen Smith 2010- 2012 : First Published Online July 2012
Researched & Written by Karen Smith 2010- 2012 : First Published Online July 2012
Apart from the Executive Summary, the information in this overview (and its complimentary report 'Lyme Disease: A Counter Argument to the Australian Governments Denial' was published on the Lyme Australia Recognition and Awareness (LARA) website in July 2012, effectively being copyrighted at that time. The ISBN publishing date reflects the year of original online publication date (July 2012), rather than the date the information was released in a PDF format (2014).
The Executive Summary of the Overview is reproduced below. The entire Overview in PDF format can be downloaded on the following link:
| Lyme Borreliosis: An Overview of Lyme and Direction for Further Research Required in Australia.pdf |
A note for those that struggle reading long documents: I have received some comments from Lyme patients that whilst they would love to read the document, their neurological symptoms means that 46 pages is simply beyond their capability. To reduce some of those fears, while the document is 46 pages long, the body of the report is only 18 pages (7-24). The remaining pages include: Cover and Information Page, Executive Summary and Contents (Pge 1-6) and the References (Pge 25-46).
Lyme Disease / Borreliosis: An Overview of Lyme and Direction for further Research required in Australia
Executive Summary
Executive Summary
Lyme disease (LD) is due to an infection from the species of bacteria belonging to the Borrelia Burgdorferi sensu lato complex. There are numerous species of Borrelia in this complex and as such LD is also known as Borreliosis and in continents such as Europe and Asia where the species responsible for neurological symptoms are more common, Neuroborreliosis. When the infection is detected and treated early, in the acute stage, the potential for full recovery is excellent. However, due to the various ways the illness can manifest, the lack of definitive laboratory tests for diagnosis and more importantly the overall lack of awareness surrounding Lyme disease, many people may go undiagnosed for long periods of time, rendering the treatment and recovery process of complicated due to the infection having widely disseminated.
Lyme is the fastest growing vector borne disease in the world. In the United States of America (USA), the Centre for Disease Control (CDC) recently released figures of around 300,000 new cases of Lyme disease each year in America alone. Although there is no official collection of data, various sources reveal that the number of cases for the other continents (Europe, Africa and Asia) range from around 200,000 to 300,000 cases per year also. According to Australian Government Health departments, Australia is the one continent exempt from a disease that affects over half a million people around the world each year.
The ‘No Lyme in Australia’ stance is maintained, despite thousands of clinically suspected cases that date back as far as the 1980’s. This position stems from research that was conducted on ticks and animals collected from New South Wales (NSW) over twenty years ago. The research was conducted by the Department of Medical Entomology (DME), Westmead Hospital, NSW and published in a paper by Russell et al., (1994) Lyme disease: search for a causative agent in ticks in south-eastern Australia.
The complimentary report to this overview - ‘Lyme Disease: A Counter Argument to the Australian Government’s Denial’ by Karen Smith (2012), - examines the research by Russell and others and outlines a number of issues with the methods utilised and questions a number of the erroneous conclusions drawn. In short, it highlights how the findings from the Russell et al., 1994 research should have encouraged further investigation, rather than simply dismissing the existence of Lyme and putting a twenty year freeze on government research.
While the counter-argument focused more exclusively on examining the problems with methods used and conclusions drawn with regards to the research underlying the denial of Lyme in Australia, the aim of this current review is to provide a brief outline of Lyme. What it is, the clinical picture and symptoms associated with the disease as well as detailed information on how it is transmitted and maintained in the environment. By outlining the basics and providing background information, it is hoped that the ‘mystery’ surrounding Lyme is lifted and that it can be very plainly seen that the likelihood that the bacteria responsible for Lyme is in Australia is quite high, and that there is an urgent need for further investigation and thorough research in this field. The information discussed in each segment of this paper is briefly outlined below.
Lyme is the fastest growing vector borne disease in the world. In the United States of America (USA), the Centre for Disease Control (CDC) recently released figures of around 300,000 new cases of Lyme disease each year in America alone. Although there is no official collection of data, various sources reveal that the number of cases for the other continents (Europe, Africa and Asia) range from around 200,000 to 300,000 cases per year also. According to Australian Government Health departments, Australia is the one continent exempt from a disease that affects over half a million people around the world each year.
The ‘No Lyme in Australia’ stance is maintained, despite thousands of clinically suspected cases that date back as far as the 1980’s. This position stems from research that was conducted on ticks and animals collected from New South Wales (NSW) over twenty years ago. The research was conducted by the Department of Medical Entomology (DME), Westmead Hospital, NSW and published in a paper by Russell et al., (1994) Lyme disease: search for a causative agent in ticks in south-eastern Australia.
The complimentary report to this overview - ‘Lyme Disease: A Counter Argument to the Australian Government’s Denial’ by Karen Smith (2012), - examines the research by Russell and others and outlines a number of issues with the methods utilised and questions a number of the erroneous conclusions drawn. In short, it highlights how the findings from the Russell et al., 1994 research should have encouraged further investigation, rather than simply dismissing the existence of Lyme and putting a twenty year freeze on government research.
While the counter-argument focused more exclusively on examining the problems with methods used and conclusions drawn with regards to the research underlying the denial of Lyme in Australia, the aim of this current review is to provide a brief outline of Lyme. What it is, the clinical picture and symptoms associated with the disease as well as detailed information on how it is transmitted and maintained in the environment. By outlining the basics and providing background information, it is hoped that the ‘mystery’ surrounding Lyme is lifted and that it can be very plainly seen that the likelihood that the bacteria responsible for Lyme is in Australia is quite high, and that there is an urgent need for further investigation and thorough research in this field. The information discussed in each segment of this paper is briefly outlined below.
* Lyme Disease
*Lyme Disease Transmission and Maintenance within the environment
*Multiple Pathogens carried by Ticks, with a focus on Babesia
A tick typically harbours multiple pathogens, therefore if bitten by one, a person may be exposed to an array of various bacteria, viruses and
parasites. The clinical picture of Lyme/severity of illness may be altered by other pathogens that a person is exposed to following a tick/vector bite.
*Conclusion
Current research investigating the pathogens that Australian ticks and the animals that are known to be reservoir hosts for Lyme / Borrelia is
essential to maximise the potential for early detection and treatment of Lyme and other vector borne diseases.
- Lyme disease is a multi-systemic inflammatory disease resulting from an infection due to bacteria from the Borrelia family – more specifically bacteria from the Borrelia burgdorferi sensu lato class.
- Clinical Picture: The clinical picture can vary depending on the species of Borrelia underlying the infection, the strength of a person’s immune system and any co-infections that may be acquired at the same time. In the initial stages Lyme disease may present with flu-like symptoms, however as the length of time of infection increases and the bacteria disseminates widely throughout the body’s tissues, organs, peripheral and central nervous systems the symptoms become more wide-ranging.
- Symptoms: The Borrelia bacterium is a spirochete and is able to move through semisolid environments, such as the body’s connective tissue, which typically inhibits the movement of most other bacteria. This action, in combination with other properties of the spirochete, allows the Borrelia bacteria to infect the entire body, resulting in symptoms that are extremely varied.
- Associations / Misdiagnosis: The ability of Borrelia to invade every organ in the body and the widespread inflammation induced is one reason that Lyme disease has been misdiagnosed as multiple diseases including: those that effect the brain/ nerves - meningitis, encephalitis, stroke ; Demyelinating and degenerative diseases - Parkinson’s disease, Motor Neurone Disease (MND) ; Heart problems - transient atrioventricular blocks ; Systemic inflammatory diseases - arthritis.
- Co-infections: A tick or other vector may transmit more than one pathogen (bacteria, virus, protozoa) at once. Infection with one or more of these pathogens at the same time can alter the severity of illness.
*Lyme Disease History and Borrelia Species - Brief History: Initial investigations regarding Lyme began in 1975. Due to the clinical picture of a cluster of children in Old Lyme, Connecticut, in the United States of America, Lyme was initially thought to be primarily arthritic in nature. In the years since, research and clinical cases have revealed that there are different species of Borrelia underlying Lyme and that the disease also has neurological and dermatological manifestations.
- Borrelia Species: In the last thirty years over 20 Borrelia species worldwide have been associated with Lyme or Lyme like illnesses.
- Table 1: Borrelia Species Associated with Lyme Borreliosis
- Pathogenicity and species diversity issues underlying identification of Borrelia: The ability to understand the pathogenicity and the development of adequate diagnostic procedures is made more difficult due to the 100’s of strain variations within the Borrelia species.
*Lyme Disease Transmission and Maintenance within the environment
- Blood sucking insects (other than ticks): Biting flies, mosquitoes and mites have been found to carry Borrelia, and are the suspected vectors in some clinical cases of Lyme.
- Contact Transmission: Contact transmission has been observed in mice, with spirochetes being found to be viable for 18-24 hours in the urine of infected animals.
- Human to Human:
- Sexual Transmission: There is no direct evidence that Lyme is sexually transmitted, however spirochetes have been found in semen.
- Mother to baby: The National Institute of Health and the CDC in America have both published information that Lyme can be passed on through pregnancy.
- How Lyme is Transmitted and Maintained within the Environment: The transmission and maintenance of Borrelia within the environment requires the tick (or vector) and the tick host and / reservoir animals. The host animals may be thought of as either reservoir hosts, which are small to medium size animals that carry/maintain the spirochete infection within their blood and the larger host animal for which the adult of a particular species of tick has an affinity.
- Ticks and Lyme Disease: Ticks are divided into two families, the Ixodidae (hard ticks) and Argasidae (soft ticks). Both are vectors for human disease, though in the case of the Borrelia underlying Lyme, it is the Ixodidae family that has been associated with transmission. The family of Ixodidae tick itself has over 600 different species, divided into numerous genera including; Ixodes, Amblyomma, Haemaphysalis, Rhipicephalus and Dermacentor.
- Table 2: Tick Vectors of Lyme Disease / Borreliosis
- Original investigations showed the number of ticks to be involved in the Borrelia cycle as limited. Over the years, research and knowledge about the number of ticks involved has grown exponentially. The existence of Lyme in Australia is still denied due to the lack of presence of the first four ticks originally found to be associated. As the table reveals, numerous other species of the Ixodidae family are implicated, and we do have some of the tick species on the table in Australia.
- Original investigations showed the number of ticks to be involved in the Borrelia cycle as limited. Over the years, research and knowledge about the number of ticks involved has grown exponentially. The existence of Lyme in Australia is still denied due to the lack of presence of the first four ticks originally found to be associated. As the table reveals, numerous other species of the Ixodidae family are implicated, and we do have some of the tick species on the table in Australia.
- The discussion in this segment examines four tick species (Ixodes uriae, I. auritulus, Haemaphysalis bispinosa and H. longicornis) from the Ixodidae family that are listed on Table Two as being involved in Borrelia transmission, and that have been recorded as being in Australia. The ticks are also explored in relation to their respective animal hosts, with the presence of both the bird and mammal hosts in Australia being examined.
- Examination of Ixode Ticks and Bird species involved in the Borrelia cycle in Australia:. Birds can carry pathogens, including Borrelia, in their blood, as well be carriers of ticks (and other vectors). This means that not only can birds drop infected ticks into new environments but as reservoir hosts, immature ticks that feed on them may become infected and spread the disease to other birds and mammals during their next feed. Land birds can spread Borrelia across continents, while migrating seabirds can spread the disease around the world.
- Seabird Tick Ixodes uriae and Associated Bird Vector & Reservoir Hosts: The I. uriae species is found Australia-wide, including offshore islands and is associated with many species of marine birds. With over 20 million migrating seabirds and 3 million plus shore-birds breeding on Australian Islands and shores each year, it is unbelievable that the health departments of Australia continue to ignore the long established knowledge that migrating birds contribute to the spread of Borrelia.
- Bird Tick Ixodes auritulus and Associated Bird & Reservoir Hosts: The I. auritulus is a native bird tick species of Tasmania. Birds that have been introduced into Australia, and are competent reservoir hosts of Borrelia, include: European blackbirds, song thrushes, wild turkeys, pheasants, quails and Mallard ducks.
- Examination of Haemaphysalis Ticks and Mammals involved in the Borrelia cycle in Australia: The Haemaphysalis ticks are discussed in conjunction with mammal hosts that have been shown to be either hosts for the tick, or those that are also reservoir hosts of the Borrelia bacteria. In order to outline the role that mammals play in the maintenance and spread of Borrelia within the environment, this section also briefly examines clinical illness in animals, contact transmission and the animals that have been introduced/ imported into Australia.
- Haemaphysalis bispinosa: Very similar attributes and animal hosts as the H. longicornis tick.
- Scrub Tick Haemaphysalis longicornis and Associated Mammal Vector & Reservoir Hosts: More commonly known as the scrub or bush tick (or cattle tick in New Zealand). It was introduced into Australia on cattle from Northern Japan and was first recognised in 1901 in north eastern New South Wales. It is now established throughout many coastal areas of Australia.
- Clinical Illness in Animals: Apart from humans, the only animals that appear to develop an illness due to Lyme are dogs, cats, horses and cattle.
- Contact Transmission in Animals: Spirochetes have been found in the urine of infected mice, dogs, horses, and cattle. Mouse studies show that the spirochetes in urine remained viable for 18-24 hours and that contact with urine appeared to be another method of transmission (similar to Leptospirosis).in rodents. Further studies are required for larger animals and humans.
- Importation of Animals into Australia: Examines Dogs, Foxes, Cattle, Horses, Sheep and Deer: These larger mammals are all involved in the Borrelia cycle, both as reservoir hosts and tick hosts. Touched on briefly also is the presence of the smaller reservoir hosts, European hares, black and brown rats in Australia that are reservoir hosts of Borrelia in the Northern hemisphere.
- Other Ixodidae Tick Species: A number of other Ixodidae tick species that have been implicated as being involved in the Borrelia cycle are examined briefly.
- Rhipicephalus Ticks: Ticks from this species have been found to carry the Borrelia spirochete and are possible vectors.
- Brown Dog Tick: Rhipicephalus sanguineus: This species has been found to harbour Borrelia in ticks both America and Europe. It is also the suspected tick vector of Borrelia in Mexico.
- Cattle Tick: Rhipicephalus Microplus: B. burgdorferi (Bb) has been isolated from this tick species. Though its ability as a vector of Bb is yet to be further examined, it is a known vector of B. theileri, the species responsible for bovine borreliosis.
- Dermacentor Species: This species of ticks is not found in Australia. They are briefly mentioned in order to demonstrate that when looking at the vector competence of a particular species of ticks that findings may be altered when ticks are examined in co-feeding studies.
- Various Ixodidae Tick Species: Paralysis Tick (Ixodes holocyclus), Wallaby Tick (Haemaphysalis bancrofti), Snake Tick (Amblyomma Morelia):1994 research reported that spirochete like objects were cultured from these tick species. These findings are looked at briefly.
*Multiple Pathogens carried by Ticks, with a focus on Babesia
A tick typically harbours multiple pathogens, therefore if bitten by one, a person may be exposed to an array of various bacteria, viruses and
parasites. The clinical picture of Lyme/severity of illness may be altered by other pathogens that a person is exposed to following a tick/vector bite.
- Babesia: Babesia is a red blood cell parasite similar to malaria. The first known case of human Babesia in Australia came to light after the death of a 56yo NSW male in April 2011. Babesia protozoa can cross the placenta and be passed from mother to foetus and they are also able survive in stored blood and be passed on through blood transfusions.
- Various pathogens carried by H. longicornis and R. Microplus: The scrub (H. longicornis) and cattle (R. Microplus) ticks carry numerous pathogens including Borrelia and Babesia. They are implicated in being the vector of both of these pathogens.
*Conclusion
Current research investigating the pathogens that Australian ticks and the animals that are known to be reservoir hosts for Lyme / Borrelia is
essential to maximise the potential for early detection and treatment of Lyme and other vector borne diseases.
Copyright information: As noted in the copyright section of this website: The information is intended to be disseminated in order to promote awareness and further research of Lyme in Australia; though I do ask that the source (myself) of the information is referenced appropriately. Information may not be used, distributed, or reproduced for any commercial purpose. Thank you. Karen Smith, B Psych (Hons).
