Definition: Defining the Meaning of Lyme Disease
Lyme disease, also known as Lyme borreliosis, is an infectious disease caused by bacteria of the Borrelia type. The most common sign of infection is an expanding area of redness, known as erythema migrans, that begins at the site of the bite about a week after it has occurred. The rash is typically neither itchy nor painful. About 25% of people do not develop a rash. Other early symptoms may include fever, headache, and feeling tired. If untreated, symptoms may include loss of the ability to move one or both sides of the face, joint pains, severe headaches with neck stiffness, or heart palpitations among others.
According to the U.S. Centers for Disease Control, there are more than 300,000 cases of Lyme disease in the U.S. each year. Last year (2013), most Lyme disease cases reported to the CDC were concentrated heavily in the Northeast and upper Midwest, with 96 percent of cases in 13 states. In fact, the disease gets its name from the northeastern town of Lyme, Connecticut, where it was first discovered.
The bacterium, 'Borrelia Burgdorferi,' causes Lyme disease, which is transmitted to people through the bite of infected Black-Legged Ticks. Symptoms of Lyme disease involve headaches, fevers, fatigue and a skin rash known as, 'Erythema Migrans.'
Untreated Lyme disease can spread to the nervous system and to the heart, as well as to the joints.
A diagnosis of Lyme disease is reached through lab testing, exhibited symptoms, and physical findings such as the characteristic rash associated with it, as well as potential exposure to ticks. Laboratory testing and results are most helpful when Lyme disease is in its later stages. In the majority of cases of Lyme disease, antibiotic treatment is successful. Prevention of Lyme disease involves taking steps such as using insect repellents, integrated pest management, and landscaping, as well as promptly removing ticks which can transmit additional diseases in addition to Lyme disease.
Transmission of Lyme Disease
Squirrels, Mice, and other small animals are carriers of Lyme disease; however, Lyme disease is transmitted to human beings through a specific species of ticks. The Black-Legged Tick, also known as the, 'Deer Tick,' found in the United States is a transmitter of Lyme disease in north-central and north-eastern areas. Along the Pacific coastal areas, the Western Black-Legged Tick is a transmitter of the disease. There are many additional species of ticks to be found in America; they haven't been found to transmit Lyme disease.
Symptoms of Lyme Disease
One of the first signs of a Lyme disease infection is usually a circular rash referred to as, 'Erythema Migrans,' which affects about seventy to eighty percent of the people who are infected after a delay of three to thirty days. The rash appears around the area of the tick bite, and expands over a period of days, potentially to a size of up to twelve inches across. An interesting feature of the rash is that the center of the rash might clear as it grows larger, making it resemble a bull's-eye. The person affected might go on to develop additional rashes on their body as days go by; the rashes may be warm, but are usually not painful. The person can also experience symptoms such as chills, fevers, fatigue, muscle and joint aches, and headaches. Sometimes these symptoms are the only ones a person will experience.
People who contact Lyme disease may experience it in different ways. Not everyone has all of the same symptoms, and the symptoms associated with Lyme disease occur with other diseases too. Lyme disease has the potential to infect many different parts of the human body, and to create various symptoms at different times. If you have been bitten by a tick and suspect that you may have Lyme disease it is important to contact a healthcare provider as soon as possible.
Seeking early treatment for Lyme disease is important because if it is left untreated there are a number of serious symptoms that can occur over additional days and weeks. 'Bell's Palsy,' is one of these symptoms, and involves a loss of muscle tone on either one or both sides of the face. Other potential symptoms that can present themselves due to untreated Lyme disease include:
- Meningitis and associated neck stiffness
- Severe Headaches
- Heart Palpitations
- Dizziness due to changes in heartbeat
- Shooting Pains which may interfere with sleeping
- Joint to Joint Pain
If several months pass without treatment for persons infected with Lyme disease, about sixty-percent of those infected will experience severe joint pain and swelling, as well as sporadic bouts of arthritis in larger joints, notably their knees. Untreated for months to years, five-percent of Lyme disease patients may experience chronic neurological issues including tingling or numbness in their hands or feet. They may also have problems with concentration, memory, or with shooting pains.
Antibiotics can cure most cases of Lyme disease if treatment is started early; however, some people with Lyme disease continue to experience symptoms for months or even years after being treated with them. The symptoms they experience can include:
- Sleep Disturbances
- Muscle and Joint Pain
- Cognitive Defects
Medical science does not know the cause of these symptoms, but there is evidence suggesting that they are the result of an autoimmune response where the immune system continually responds, even though the infection is no longer present.
Diagnosing Lyme Disease
A diagnosis of Lyme disease is made based upon the symptoms the patient presents, any objective physical findings such as the characteristic, 'bulls-eye,' rash in company with arthritis or facial palsy, as well as a potential exposure to a tick bite. Laboratory tests are available for Lyme disease, but they are not recommended for people who have the characteristic rash, or for people who do not have symptoms of Lyme disease. The rash associated with Lyme disease doesn't appear in everyone, and the symptoms of Lyme disease are similar to other diseases.
Blood Testing for Lyme Disease
Many of the recommended tests for Lyme disease are blood tests which measure antibodies created in response to the infection. Patients who are have recently been exposed to Lyme disease may receive false negative results from blood testing, but testing is highly reliable for persons in later stages of the disease. There are several forms of lab tests for Lyme disease; some of them have not been validated. The Centers for Disease Control (CDC) is recommending a two-step process of blood testing for Lyme disease which can use the same blood sample.
Step one involves the use of an ELISA or IFA test, designed for sensitivity to Lyme disease to the point where nearly everyone who has it (and even some people who do not) will test positive for the disease. If either IFA or ELISA testing returns negative the potential for the person being infected with Lyme disease is very unlikely, and further tests are not recommended. If the test comes back positive a second test is done to confirm the results found.
Step two involves the use of a, 'Western Blot Test,' which is designed to return a positive result only if the person is truly infected with Lyme disease. If the Western Blot Test results are negative it suggests that the ELISA or IFA test results were a false positive. At times, there are two kinds of Western Blot Test that are done; an, 'IgM,' and an, 'IgG.' People who are positive for the IgM test, but not the IgG test need to have the tests run again after a few weeks if they continue to have symptoms of Lyme disease.
If a person is positive for the IgM test only, but has been sick for more than a month, then the test results probably represent a false positive. The CDC recommends testing with ELISA or IFA before using the Western Blot Test because it decreases the potential for false positive results, and prevents people from being treated for Lyme disease when they do not have it and need treatment for another disease.
Treatment and Prognosis of Lyme Disease
There are a number of studies on the treatment of Lyme disease which are funded by the National Institutes of Health (NIH), showing that people can be cured over a few weeks period of time by taking oral antibiotics. Amoxicillin, Doxycycline, and Cefuoxime Axetil are among the more common antibiotics used in the treatment of Lyme disease. Some patients who have either cardiac or neurological illnesses might need intravenous treatments with antibiotics such as Penicillin or Cetriaxone.
The recover of people who have taken antibiotics for Lyme disease during the early stages is usually quick and complete. Some people who are diagnosed when Lyme disease is in its later stages have recurrent and persistent symptoms, and studies at the National Institutes of Health suggest that a second course of antibiotics might help them. An additional four weeks worth of antibiotics might help, but longer courses of antibiotics could cause serious complications or even death.
Some antibiotics may affect an unborn child, and are not used in treatment of Lyme disease in pregnant women because of this. There have been studies done in relation to women who have Lyme disease that are also pregnant, the results of which have shown that there are no negative effects on the fetus if the mother has received treatment with certain antibiotics. It is always a good idea to discuss concerns with your healthcare worker prior to treatment.
Update Sept. 11, 2014 - Lyme Disease in North Dakota
A new article published in the Journal of Medical Entomology reports that the ticks that vector Lyme disease - Ixodes scapularis, also known as black-legged ticks or deer ticks - are moving westward, and for the first time have been found to be established in North Dakota. Even worse, deer ticks that were infected with the bacterium that causes Lyme disease (Borrelia burgdorferi) were found as well. Researchers sampled ticks at nine locations throughout North Dakota by trapping small mammals and then removing the attached ticks. When they found I. scapularis, they screened them for Borrelia burgdorferi and for two other types of bacteria that can lead to two other tick-borne diseases called Anaplasmosis and Babesiosis.
Lyme Disease Awareness Information
The awareness ribbon color for Lyme Disease is Lime Green. The month of May is Lyme Disease Awareness Month. In recognition of Lyme Disease Awareness month, the Centers for Disease Control and Prevention reminds Americans to learn about this common tick-borne disease and take steps to protect themselves if they live in or visit areas with Lyme disease activity. World Lyme Disease Day is held on May 11th.
Quick Facts: Lyme Disease
If a tick is removed within 24 hours, the chances of it transmitting Lyme disease or other infections are much less because the risk of contracting Lyme disease and other infections caused by ticks increases between 24 to 72 hours after the tick attaches to the skin.
How to Remove a Tick to Prevent Lyme Disease - Disabled World - (2009-02-16)
Currently, there is no prophylactic treatment and no vaccine against the infection. In the future, a new type of gel is supposed to nip the infection in the bud: the patient applies it locally immediately after the tick's bite.
First Aid for Lyme Disease After a Tick Bite - Fraunhofer-Gesellschaft - (2011-12-19)
Statistics: Lyme Disease
Lyme disease is the most common tick-borne disease in North America and Europe, and one of the fastest-growing infectious diseases in the United States. Each year, approximately 30,000 new cases are reported to the CDC however, this number is likely underestimated.
The CDC is currently conducting research on evaluation and diagnostics of the disease and preliminary results suggest the number of new cases to be around 300,000. The ratio of Lyme disease infection is 7.9 cases for every 100,000 persons. In the ten states where Lyme disease is most common, the average was 31.6 cases for every 100,000 persons for the year 2005.