This page provides an overview with basic information about Lyme disease.
Lyme disease is an infectious disease that is caused by the bacterium Borrelia burgdorferi (Bb), which is a spirally shaped type of bacterium that is called a spirochete. In 1981 researcher Willy Burgdorfer discovered this new bacterium in ticks (bloodsucking parasites), a bacterium belonging to the genus Borrelia.
The bacterium was named Borrelia burgdorferi after its discoverer. Not long after its discovery it was also established that Borrelia burgdorferi is the cause of Lyme disease, a disease recognized around the town Old Lyme, Connecticut, in the Unites States of America in the 1970s by researcher Allen Steere. The medical name is Lyme borreliosis. So the name "Lyme" origins from the name of a town, not a name of a doctor or researcher. In German language they use the name Borreliose.
Lyme disease is predominant on the northern hemisphere in temperate climates, which goes together with the spread of ticks. On a world map it is a band going over the Unites States, Europe, and across central Asia all the way to japan.
One can become infected with Borrelia burgdorferi by the bite of an infected tick. Ticks are small bloodsucking parasites that occur mainly in forests and fields, but also in gardens. The tick attaches itself into the skin and sucks blood. During a tick bite Borrelia burgdorferi can be transmitted from the tick to the host (the animal or human the tick is biting).
There is also evidence that a pregnant woman who is infected with the Lyme disease bacterium can pass it over to the unborn child. However, there is no consensus on whether this will cause Lyme disease in the child and if so, how often this happens.
There are several other routes of infection that are suspected by some, including breastfeeding, human and animal contact, blood-sucking insects (mosquitoes, flies, fleas), blood transfusions and transplants, but neither of these routes of infection have been scientifically established (yet). So Lyme disease is not known to be contagious.
Early Lyme disease symptoms are the characteristic Lyme disease rash called erythema migrans: an expanding red ring or rings (called bullseye rash) or spot at the location of the tick bite, and flu-like complaints like headache, stick neck, fever, muscle aches and fatigue. These symptoms do not occur in all people.
Symptoms and the course of the disease differ somewhat between children and adults, as well as between men and women, but generally many of the same symptoms occur.
In late Lyme disease, various symptoms can develop because Lyme disease is a multi-system disease. It can cause neurological (nervous system/brains: meningitis), dermatological (skin), rheumatological (muscles and joints), cardiological (heart), ophthalmological (eyes) and psychiatric symptoms (cognition, personality, behavior).
There are three Lyme disease stages:
Lyme disease is a clinical diagnosis. This means that the physician must make the diagnosis on the basis of the medical history, history of tick bite or tick exposure, signs and symptoms, and results of physical examination, in combination with other data like Lyme disease test results, exclusion of other diagnoses.
Upon seeing a typical erythema migrans the doctor should make the diagnose "Lyme disease", because it is specific for Lyme disease. Therefore make sure you always take pictures of an erythema migrans or any other rashes that might be related to Lyme disease. Without an erythema migrans it is often more difficult to establish the diagnosis of Lyme disease. Often Lyme disease tests are then used.
Specifically, Lyme disease blood tests that look for antibodies are used, so-called serological tests. The most common types of tests used are the ELISA and blot (immunoblot and western blot) tests. These Lyme disease tests look for IgG and IgM antibodies against Borrelia burgdorferi. These antibodies are created by the immune system to fight the infection.
If a patients tests positive, it indicates exposure to the Lyme disease bacterium. However, it doesn't necessarily imply that there is an active infection, because the antibodies remain in the body after the infection is gone, although the concentration (the Lyme titer) goes down in time.
These tests are to support a clinical diagnosis. A diagnosis should not be made on the basis of test results alone. For various reasons the tests results can give both false positive and false negative results. Such tests are not 100% sensitive and specific. Usually a certain diagnosis can not be established, only the most probable.
Lyme disease can cured with antibiotics if this happens in an early stage of the disease. When one has been infected for a longer time, it becomes more difficult to treat Lyme disease successfully. Symptoms may remain after treatment and it is subject to debate what is causing those symptoms, whether it's still caused by an infection with the Lyme disease bacterium or something else.
Most Lyme disease guidelines advise antibiotic treatment durations ranging from one week to one month and only if there is clear evidence that the infection has not been eradicated, a longer or repeated course of antibiotics is advised.
There are also some doctors and organizations that advise longer and higher doses antibiotic treatment.for Lyme disease. However, until now it has not been scientifically established with studies that such treatments have a higher success rate.
Lyme disease is curable with several types of antiboitics including common antibiotics like doxycycline, amoxicillin and azitromycin, which can be taken orally. Sometimes the antibiotic is administered intravenous (IV), particularly when the drug of choice is ceftriaxone (Rocephin), which cannot be taken orally.
Other antibiotics used include: minocycline, tetracycline, cefuroxim, claritromycin. Some doctors also experiment with other types of antibiotics or combinations of antibiotics. Many of those treatment have not been studied, though.
In the 1980s and 1990s the term "chronic Lyme disease" was mostly used as a synonym of "Late Lyme disease". However, somewhere around the year 2000 some organizations, especially in the Unites States, began to use this term to refer to post-treatment Lyme disease symptoms, supposedly without objective evidence of previous or current infection. Post-treatment infection and continuing use of antibiotics is a very controversial subject regarding Lyme disease.
Even in the 2010s, organizations, doctors and researchers regularly use the term "chronic Lyme disease" to refer to a late stage of Lyme disease, especially in Europe. This confusion on the definition of the term has only added up to controversial about chronic Lyme disease.
Lyme disease is not the only tick-borne disease. Ticks can also be carriers of other pathogens besides Borrelia burgdorferi. These infections are often called co-infections, particularly when they coexist with the Lyme disease bacterium. Worldwide, various co-infections occur, sometimes limited to a specific region, like in the Unites States or Europe.
Some other common tick-borne infections are: Rickettsia, Tularemia, Bartonella, Babesia, Anaplasma (Erhlichia), Tick-borne encephalitis virus (TBEV), and Borrelia species that cause relapsing fever. One tick can carry multiple types of such pathogens.
Lyme disease prevention begins with avoiding exposure to ticks by avoiding tick infected areas, or at least staying on the paths in forests, avoiding contact with grasses and bushes. Pet owners can use special tick repellents for their dog or cat.
Further, one can prevent a tick bite by using tick repellents, keeping the body covered with clothes, doing body tick checks, wear light-colored clothes do you can see tick on them more easily and tuck your clothes.
In case one has a tick bite the tick needs to be removed from the skin properly and as quickly as possible. The longer attached, the higher the chance of an infection. One of the best tools to remove a tick is a fine-tipped tweezers, with which you can work precise and grab the tick firmly.
After tick removal one should be alert for symptoms, particularly the Lyme disease rash erythema migrans and flu like symptoms. It is also possible to take a course of prophylactic treatment with antibiotics, but this is not standard procedure. Recent studies on only a single dose of an antibotic as a prophylaxis have been carried out, suggesting that some of them have protective value to some extent.
The has also been a Lyme disease vaccine for humans, called LYMErix, on the market in the Unites States in the late 1990s and early 2000s. However, it was withdrawn from the market by developer GlaxoSmithKline in February 2002. Its safety and efficacy has been subject to fierce debate.
Besides humans, pets and other animal can also get Lyme disease. Lyme disease and/or Borrelia burgdorferi infection has been described in dogs, cats and horses. Possibly cattle is affected as well. In animals, clinically apparent disease is found primarily in dogs. Lyme disease in dogs, cats and horses is even more difficult to establish than in humans.
Because of the difficulties in finding sufficient indicative clinical signs, additional information (detailed case history, laboratory testing for antibodies) is especially important to make the clinical diagnosis of Lyme borreliosis.
Note that dogs and cats can also easily take ticks that bit them into the house, giving the risk for pet owners to get a tick bite even in or around the house via their cat or dog.