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Lyme Disease (Borreliosis)

Lyme disease is transmitted to humans through the bite of an infected blacklegged deer tick. It is the most common tickborne infectious disease in the United States.

PubMed Health Glossary
(Source: NIH - National Institute of Allergy and Infectious Diseases)

About Lyme Disease

Lyme disease, or borreliosis, is caused by the bacterium Borrelia burgdorferi and is transmitted to humans through the bite of an infected blacklegged deer tick.

It is the most common tickborne infectious disease in the United States. State health departments reported 27,203 confirmed cases and 9,104 probable cases of Lyme disease to the Centers for Disease Control and Prevention in 2013.


Typically, the first symptom of Lyme disease is a rash known as erythema migrans, which starts as a small red spot at the site of the tick bite and gets larger over a period of days or weeks, forming a circular or oval-shaped red rash.

The rash may look like a bull's eye, appearing as a red ring around a clear area with a red center. It appears within a few weeks of a tick bite and usually occurs at the place of the bite. The rash can range in size from that of a small coin to the width of a person's back. As infection spreads, rashes can appear at different sites on the body...Read more about Lyme Disease NIH - National Institute of Allergy and Infectious Diseases

What works? Research summarized

Evidence reviews

Efficacy of antibiotic prophylaxis for the prevention of Lyme disease: an updated systematic review and meta-analysis

This review concluded that there was available evidence to support the use of antibiotic prophylaxis for the prevention of Lyme disease in endemic areas following an Ixodes tick bite. The authors' conclusions reflected the evidence presented but, given the lack of intention-to-treat analysis and low event rates, a degree of caution might be required to interpret the authors' conclusions.

Drug Class Review: Disease-modifying Drugs for Multiple Sclerosis: Final Update 1 Report [Internet]

We compared the effectiveness and safety of disease-modifying drugs for the treatment of multiple sclerosis: Glatiramer acetate (Copaxone®), interferon beta-1a (Avonex®, Rebif®), interferon beta-1b (Betaseron®, Extavia®), mitoxantrone (Novantrone®), and natalizumab (Tysabri®).

Anaemia Management in Chronic Kidney Disease: Partial Update 2015 [Internet]

Anaemia is defined internationally as a state in which the quality and/or quantity of circulating red blood cells is below normal. Blood haemoglobin (Hb) concentration serves as the key indicator for anaemia because it can be measured directly and has an international standard. In response to low tissue oxygen levels in anaemia the kidney produces the hormone erythropoietin which stimulates the bone marrow to produce red blood cells. A major cause of the anaemia of chronic kidney disease (CKD) is a reduction in erythropoietin production due to kidney damage.

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Summaries for consumers

Ticks: Lyme disease

Some ticks carry Lyme disease and can infect people by biting them. Removing ticks at an early stage may prevent infection. Lyme disease is usually treated with antibiotics. In rare cases the disease can lead to complications if not treated properly.Lyme disease is an infectious disease caused by bacteria. At first the skin surrounding the tick bite becomes inflamed. After some time it may affect joints and various organs too. Usually it does not cause any serious problems. Lyme disease is more common than TBE, which can also be carried by ticks.It is normal for the skin around a tick bite to turn red and itch. This inflammatory reaction has nothing to do with Lyme disease and goes away within a few days after removing the tick. However, if the site of the tick bite turns red a few days or weeks after being bitten, it could be a sign of Lyme disease. The rash associated with Lyme disease is typically circular and spreads until it reaches a diameter of more than five centimeters. Because this rash usually clears in the center, it is also known as “bull’s-eye rash.”It is important to see a doctor if you develop a rash like this. You should also see a doctor if you get flu-like symptoms such as a fever, headaches, fatigue or muscle pain within six weeks of being bitten by a tick. These symptoms could also be a sign of Lyme disease, even if you do not have a bull’s-eye rash.Doctors can find out whether you have Lyme disease by giving you a physical examination. Make sure you remember to tell your doctor that you were bitten by a tick if you have symptoms. If a physical examination is not enough, you may have a blood test for Lyme disease.

Ticks: Overview

In this topic we would like to give you a realistic idea of how likely you are to get ill if you are bitten by a tick. Please note that this information reflects the situation in Germany and may not be applicable to other parts of the world. You will also find out what you can do to prevent tick bites and possible complications.

Ticks: Tick-borne encephalitis (TBE)

The risk of getting TBE is much lower than the risk of getting Lyme disease. Only a small proportion of ticks are infected with the virus. And even if a tick is infected, the virus will not necessarily spread to the people the tick feeds on.If the infection does spread, some people will develop symptoms. In children the infection often goes unnoticed, or the symptoms are only mild and temporary. The symptoms of a mild TBE infection are similar to flu symptoms: fever, headaches, vomiting and dizziness.TBE is diagnosed by testing blood or cerebrospinal fluid for the TBE virus.So far, there is no treatment that specifically fights the TBE virus. Instead, treatment only focuses on relieving the symptoms. Because TBE is caused by a virus, antibiotics do not help. No antiviral drugs are currently available.Although TBE usually clears up without any lasting health problems, the symptoms can last for months. In very rare cases it can be fatal. Serious complications are quite a lot more common in adults than in children. Children normally only have a mild form of TBE: serious symptoms are rare and there are hardly ever any lasting effects.

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More about Lyme Disease

Photo of an adult

Other terms to know:
Borrelia Burgdorferi Bacteria (Lyme Disease Bacteria), Erythema, Ticks

Related articles:
Ticks and How To Remove Them

Keep up with systematic reviews on Lyme Disease:


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