Lyme Disease

Medically Reviewed By William C. Lloyd III, MD, FACS

What is Lyme disease?

Lyme disease is an infectious disease caused by the bacterium Borrelia burgdorferi, which is transmitted through tick bites. The infection resulting from these bites causes swelling, joint pain, rash, and flu-like symptoms. The disease can affect the nervous system, as well, causing headaches, dizziness, and other symptoms.

Lyme disease is spread by the deer tick (species Ixodes scapularis) in the northeastern United States and the western black-legged tick (species l. pacificus) in the Pacific Northwest. These ticks are typically found in wooded areas where deer are present. The tick carries the B. burgdorferi bacterium, which it passes to humans when it bites them.

In the United States, Lyme disease is the most common disease borne from an arthropod (insect, spider), up from sixth place in 2015. The Centers for Disease Control and Prevention received about 42,000 case reports in 2017, but they estimate the true case count could be as high as 300,000 annually, based on medical claims databases. Most reported cases are concentrated in the northeast part of the country: Maine, Vermont, Pennsylvania, New Hampshire, and Rhode Island have the highest incidence of Lyme disease. The disease is named after Lyme, Connecticut, where the disease was first identified in the 1970s. Of reported cases, Lyme disease is most common in 5- to 9-year old boys. Men (peaking again at age 50) are more commonly affected than women until age 70, when confirmed cases in women slightly outnumber men.

Lyme disease begins with the appearance of a red spot at the site of the tick bite within days to weeks following the bite. The spot may expand into a circular or oval-shaped rash and resemble a bull’s-eye: red in the center with alternating circles of white and red around it. This rash is known as erythema migrans and is unique to Lyme disease. Eventually, the rash will spread to different sites on the body. Additional symptoms include fever, aches, stiff neck, and other flu-like symptoms.

The symptoms of Lyme disease can be serious and may worsen without antibiotic treatment. Untreated cases can lead to chronic arthritis (inflammation of the joints), swelling or inflammation of the nerve that controls facial muscles, and even paralysis. Infection can spread to the spine, brain and heart as well. This can also happen if treatment is delayed or does not cure the infection.

Seek prompt medical care if you experience rash, fever, muscle aches, headache, or other symptoms of Lyme disease after being bitten by a tick.

What are the symptoms of Lyme disease?

Symptoms of Lyme disease include rash, fever, aches and swelling. You may feel like you have the flu. Left untreated, symptoms can become more serious and include joint swelling and arthritis (inflammation of the joints), especially of the knees. Lyme disease can also affect the nervous system, causing stiffness, headache, loss of muscle tone, and even paralysis.

Common symptoms of Lyme disease

Lyme disease causes symptoms that range in type and severity among individuals and may include:

  • Aches

  • Chills

  • Decreased vision

  • Fatigue

  • Fever

  • Headache

  • Muscle pain

  • Neuropathy (Bell’s palsy, transverse myelitis)

  • Rash, starting with a bull’s-eye appearance that spreads over time

  • Stiff neck

  • Swelling of the knees and other large joints

  • Swollen lymph nodes

Serious symptoms that might indicate a life-threatening condition

In some cases, Lyme disease can be a serious condition that should be immediately evaluated in an emergency setting. Because its symptoms can progress to serious conditions, it is important for you to be treated right away. Seek immediate medical care (call 911) for any of these serious symptoms including:

  • Abnormal pupil size or nonreactivity to light

  • Fever

  • Heart palpitations and dizziness due to changes in heartbeat

  • Loss of muscle tone on one or both sides of the face, possibly indicating paralysis

  • Pain that moves from joint to joint

  • Severe headaches and neck stiffness, possibly indicating meningitis (infection or inflammation of the sac around the brain and spinal cord)

  • Severe swelling in the knees or joints

  • Weakness or paralysis in the muscles of the face

What does Lyme disease look like?

One of the telltale symptoms of Lyme disease is erythema migrans, a red rash at the site of the tick bite:

circular bull's eye tick bite rash on man's lower leg, a sign of Lyme disease

What are the stages of Lyme disease?

The stages of Lyme disease are progressive and depend on treatment interventions:

  • Early localized, just after the infection takes hold. Symptoms begin within hours, days or weeks after the tick bite, and can include skin rash—the characteristic bull’s-eye rash (erythema migrans)—as well as flu-like symptoms and joint pain.

  • Early disseminated, occurring weeks to months after the tick bite. The bacteria are spreading further throughout the body. Because more body systems are infected, symptoms are varied and may not look related. Symptoms include eyesight problems, rash in other areas, irregular heartbeat, pain, and nerve symptoms like numbness in the arms and legs or the face.

  • Late disseminated stage, occurring weeks, months and extending months after the tick bite. Left untreated, Lyme disease can lead to such chronic conditions as arthritis, migraine, widespread pain, difficulty sleeping, and trouble concentrating.

What causes Lyme disease?

Lyme disease is an infectious disease caused by the bite of a tick infected with Borrelia burgdorferi bacteria. These are in the spirochete class of bacteria, which includes the T. pallidum bacterium that causes syphilis. The deer tick in the Northeast and the western black-legged tick in the Pacific Northwest carry B. burgdorferi. The more recently discovered Borrelia mayonii can also cause Lyme disease. Transmission to humans occurs most commonly in the summer when people are most likely to be outdoors and ticks are most active.

Lyme disease bacteria usually live in rodents and other small animals and are transmitted when a tick bites an infected animal. The bacteria live in the gut of the tick. When the tick bites a human, bacteria from an infected tick can pass from the tick into the person’s bloodstream.

For an infected deer tick to transmit the bacteria, it typically needs to feed for more than 36 hours. The longer the tick is attached and feeding, the greater the likelihood of the person developing Lyme disease. Rather than larger, adult ticks, smaller nymph-stage ticks (about 2 mm in diameter) cause most cases of Lyme disease because they are more likely to bite humans and are harder to detect. However, most people bitten by a tick do not develop Lyme disease.

Lyme disease symptoms typically develop between 3 and 30 days, the incubation period for B. burgdorferi. There is evidence the severity of disease and symptoms depends on the person’s immune system. In other words, some people may be more at risk than others for developing Lyme disease.

It’s possible to become infected a second time and develop Lyme disease again after an initial infection and treatment for Lyme disease.

What are the risk factors for Lyme disease?

A number of factors increase the risk of developing Lyme disease. Not all people with risk factors will get Lyme disease. Risk factors for Lyme disease include:

  • Autoimmune disease (overactive immune response that causes the body to attack its own cells) or other conditions that compromise your immunity

  • Contact with animals, especially those that are prone to tick bites

  • Exposed skin unprotected by insect repellant and clothing

  • Extensive time spent outdoors, especially in the spring and summer

  • Extreme youth or advanced age

  • Hiking or camping in tick-infested areas

  • Pregnancy

Reducing your risk of Lyme disease

You may be able to lower your risk of Lyme disease by:

  • Applying insect repellent containing DEET if you will be outside in areas known to have deer and black-legged ticks

  • Avoiding areas of potential tick infestation

  • Inspect the body for ticks when changing clothes after being outdoors (adults and children)

  • Removing leaf debris, brush, and wood piles from your property

  • Wearing light-colored clothing (allowing ticks to be more easily spotted and removed)

  • Wearing long-sleeved shirts, tucked-in pants, and high boots if entering areas of possible infestation

What is the best way to remove a tick?

To remove a tick, use fine-point tweezers to hold the tick as close to its entry point in the skin as possible. Pull back firmly in a controlled motion without jerking or twisting the tick. Gently wash the area and disinfect it with a cotton ball soaked in rubbing alcohol or an alcohol wipe.

The tick can be saved in a plastic bag for testing. However, the Centers for Disease Control and Prevention (CDC) does not recommend testing ticks for the disease. Just because a tick is carrying the disease-causing bacteria doesn’t mean it has been transmitted through a bite. If the tick tests negative for bacteria, it doesn’t exclude the possibility of infection from a different tick bite.

What are some conditions related to Lyme disease?

Other bacterial infections and diseases spread by ticks include:

  • Southern tick-associated rash illness (STARI), transmitted by the lone star tick, with symptoms including rash, fatigue, fever, headache and joint pain.

  • Rocky Mountain spotted fever, transmitted by the bite of a tick infected with Rickettsia bacteria, with symptoms including rash, fever and headache.

  • Tularemia, transmitted by ticks and deer flies infected with Francisella tularensis bacteria, with symptoms including a skin ulcer at the bite site, swollen lymph nodes, and high fever.

In addition, the nonspecific and variable nature of many Lyme disease symptoms can delay its diagnosis. Conditions with symptoms overlapping with those of various stages of Lyme disease include chronic fatigue syndrome, fibromyalgia, mononucleosis, meningitis, septic arthritis, cancer, and lupus, among others.

How do doctors diagnose Lyme disease?

An accurate diagnosis requires a physician experienced with the signs and symptoms of Lyme disease. For early Lyme disease, the most common clinical sign is the bull’s eye rash (erythema migrans). The doctor also considers the patient’s confirmed tick bite or probable exposure to deer ticks in a Lyme disease diagnosis. The fact that symptoms associated with Lyme disease—fatigue, difficulty concentrating, flu-like symptoms, and joint pain—overlap with several other conditions can delay diagnosis.

If the doctor is not considering the possibility of Lyme disease, it will probably not be diagnosed. If you have signs and symptoms of Lyme disease, it is fine to ask the healthcare provider, “Could this be Lyme disease?” Remember that symptoms may develop up to 30 days after the tick bite, although typically 7 to 14 days after the bite. If the problem persists and your provider is unable to determine a cause, seeking a second opinion may give you more information and answers.

A two-step blood test that detects antibodies to the bacteria is available to help confirm a Lyme disease diagnosis. Both tests must be positive to confirm Lyme disease. Results are likely to be negative the first few weeks after infection because the body has not yet built up enough antibodies for the test to detect. The Lyme disease test is most accurate a few weeks after infection.

What are the treatments for Lyme disease?

A 10- to 14-day course of antibiotics in pill form early after infection can often cure Lyme disease. Antibiotics can also be effective in the later stages of disease, but the outcome varies among individuals. Patients in later stages of Lyme disease—those with acute joint pain or showing signs the infection has spread to the heart or central nervous system (brain and spinal cord)—may require intravenous antibiotics in a hospital.

In addition to antibiotic treatment, doctors may prescribe medicine or treatment to relieve Lyme disease symptoms, such as arthritis. You can take over-the-counter pain relievers for fever and pain.

Lyme disease recovery is usually rapid and complete, although some symptoms may recur or persist if the diagnosis is made at a later stage of the disease. It is important to follow your treatment plan for Lyme disease precisely and to take all of the antibiotics as instructed by your healthcare provider to avoid reinfection or recurrence. However, even with appropriate antibiotic treatment, the bacteria may not clear completely, and long-term and sometimes debilitating consequences are possible.

Primary care providers can treat uncomplicated cases of Lyme disease. If you have later-stage, disseminated Lyme disease, an infectious disease specialist may treat you. Other specialists you may see include a neurologist, cardiologist and rheumatologist.

Antibiotics for Lyme disease treatment

Antibiotics for Lyme disease include:

Long-term antibiotic treatment is not more effective than the normal length of antibiotic treatment. In fact, extended antibiotic therapy can carry significant health risks, including possible bloodstream infections or heart tissue damage.

Alternative treatments for Lyme disease

Many people are interested in alternative treatments for Lyme disease. While they may help with symptoms, they do not cure the infection or the disease. Products may be labeled “natural” but that does not mean they are safe. Before you try them, confirm your diagnosis with a licensed healthcare provider with the expertise necessary to rule out other possible causes of your symptoms. Explain your interest in alternative treatment, and discuss the goals, benefits and risks of these treatments compared to traditional medicine, including antibiotics.

Alternative treatments may include:

  • Acupuncture
  • Herbal supplements, such as turmeric and cilantro
  • Homeopathic medicine
  • Medical marijuana
  • Vitamin supplements

Use caution with alternative treatments

A 2015 report identified 30 alternative therapies marketed to people who believe they have Lyme disease or some variation of it, what some people refer to as “chronic Lyme disease” or “post-Lyme disease syndrome.” There are no effectiveness studies in humans for the following alternative therapies:

  • Heat therapy, including lasers and Rife therapy with magnets
  • Heavy metals and chelation, including removal of mercury-containing amalgam fillings and root canals
  • Herbal remedies
  • Oxygen therapy, including hyperbaric oxygen, ozone and hydrogen peroxide
  • Pharmacological therapy

How does Lyme disease affect quality of life?

For most people with Lyme disease, treatment is successful and there is no long-term damage or complications.

Untreated Lyme disease can progress to infect multiple body systems causing significant nervous system and heart problems. The longer Lyme disease bacteria are in the body and the farther the infection spreads, the more difficult it is to cure and the greater the risk for complications and poor quality of life.

Symptoms that can last from weeks to months include:

After antibiotic treatment for Lyme disease, up to 10% of patients develop post-treatment Lyme disease syndrome (PTLDS or PLDS). PTLDS can persist for many months. Signs and symptoms of PTLDS are similar to early-stage Lyme disease and include fatigue and joint and muscle aches and pains. Patients also report difficulty sleeping, memory problems, and headache.

Some people use the term chronic Lyme disease to describe a condition marked by symptoms like Lyme disease, such as fatigue, pain, memory problems, and arthritis. However, in many of these cases, lab tests for current or past Lyme disease are negative. For this reason, Lyme disease experts support no longer using the term chronic Lyme disease.

What are the potential complications of Lyme disease?

Most cases of Lyme disease can be cured with antibiotics, especially if treatment is begun early in the course of illness. However, a small percentage of people with Lyme disease have symptoms that last for months to years after treatment with antibiotics.

Complications of Lyme disease range from joint pain and stiffness to meningitis (infection or inflammation of the sac around the brain and spinal cord) and paralysis. About 10 to 20% of untreated or complicated cases of Lyme disease can progress to arthritis.

You can help minimize your risk of serious complications by following the treatment plan you and your healthcare professional design specifically for you. Complications of Lyme disease include:

  • Arthritis

  • Cognitive deficits (for example, memory loss and shorter attention span)

  • Fatigue

  • Meningitis (infection or inflammation of the sac around the brain and spinal cord)

  • Muscle and joint pain

  • Paralysis

  • Permanent vision loss

  • Sleep disturbances

What is the survival rate and prognosis for Lyme disease?

In rare cases, Lyme disease can be fatal. The most serious threat comes from Lyme disease bacteria entering heart tissue. This is Lyme carditis, which affects about 1% of people with Lyme disease. The infection can disrupt the heart’s electrical system causing heart block, which can be fatal if not recognized and treated rapidly.

Lyme disease awareness

The number of Lyme disease cases has been increasing over the last 25 years. Improvements in prevention will help control these numbers. To prevent Lyme disease, avoid areas known to harbor infected ticks, use insect repellent, perform a body check after being outdoors, and remove ticks as soon as possible. A Lyme disease vaccine was approved in 1998; however, sales decreased significantly and the company stopped making it in 2002. Research is underway on newer types of Lyme disease vaccines.

May is Lyme disease awareness month. Learn more about Lyme disease awareness at Global Lyme Alliance and Lyme disease research Trusted Source Centers for Disease Control and Prevention (CDC) Governmental authority Go to source efforts at the CDC.

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    Medical Reviewer: William C. Lloyd III, MD, FACS
    Last Review Date: 2021 Aug 28
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