Lyme Disease Awareness Month: What Is Lyme Disease?
May is Lyme disease awareness month. Lyme disease (not Lymes disease) is also referred to as Lyme Borreliosis, an indication of the cause of this often-debilitating condition—the pleomorphic Borrelia bacteria.
Lyme disease is caused by Borrelia bacteria transmitted by ticks and other biting insects. Several species of Borrelia are implicated, with Borrelia burgdorferi the one most discussed. It is predominantly transmitted via ticks from deer, sheep or dog. The tick bites the human, and can remain attached for hours or weeks, regurgitating into the bloodstream and passing Borrelia and other pathogens (other bacteria, and sometimes parasites and viruses) to the human host.
Borrelia burgdorferi is pleiomorphic—which means it has many shapes or forms. The spirochetal form is the active form. In this corkscrew-shaped form, Borrelia can attack multiple body organ systems, a feature it shares with another well-known spirochete Treponema pallidum which causes syphilis.
The Borrelia bacteria cycle between different forms. In its inactive (non-spirochetal) forms, Borrelia is least susceptible to therapies, during which it may alter shape and form biofilm-like colonies to survive unfavourable conditions.
Borrelia bacteria are difficult to kill because they have a stealth mode—an ability to evade destruction by the host (human, dog, sheep or deer) immune system by mutating its gene structure and outer surface proteins. In addition to its ability to evade host immunity, Borrelia bacteria actively suppress (and cause widespread disruption to) the immune system, alongside inflammation and suppression of detoxification systems.
Lyme disease was first reported in 1975 in Lyme Connecticut where a cluster of children and adults experienced uncommon arthritic-like symptoms. In 1977 the Ixodes scapularis tick was linked to transmission of the disease. It was not until 1982 that William Burgdorfer identified the bacteria as its cause; the spirochetal bacteria was named Borrelia burgdorferi in his honour.
Borrelia burgdorferi is, however, a 15 million-year-old bacterium, with its oldest known carrier being 5,300-year-old Otzi the Iceman who was determined to be infected with Lyme spirochetes when he died.
Although not a new phenomenon, Lyme borreliosis is an emerging disease –meaning its incidence has increased over recent decades. It was only 40 years ago that the tick was determined to be causative agent of Lyme and the collection of diverse symptoms.