What Is Lyme Disease?

Lyme disease spreads through the bites of infected ticks, causing a "bulls-eye" rash and flu-like symptoms.

Lyme disease is a tick-borne illness that spreads through the bite of infected blacklegged ticks, also called deer ticks. One of the most common causes of Lyme disease in the United States is the bacteria Borrelia burgdorferi. Typically, the tick must remain attached to its host for at least 36 hours to transmit the bacteria.

Lyme disease causes many symptoms, such as a "bulls-eye" rash, fever, headache, and fatigue. Most people recover fully with a course of antibiotics. If untreated, people with Lyme disease can develop severe symptoms or complications.

The Centers for Disease Control and Prevention (CDC) reports about 30,000 cases of Lyme disease yearly. Still, some estimates suggest that many cases go unreported, with nearly 476,000 cases yearly.

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Lyme Disease Symptoms

Lyme disease can affect the entire body, including the skin, joints, nerves, and heart. It takes three to 30 days for early signs of Lyme disease to appear.

The classic sign of Lyme disease is a skin rash in a bulls-eye pattern. Not everyone gets or notices this rash, nor does it always resemble a bulls-eye. Some people develop raised or oblong rashes.

Some people may have flu-like symptoms, such as:

  • Chills
  • Fatigue
  • Fever
  • Headache
  • Muscle or joint pain
  • Swollen lymph nodes

Symptoms may differ depending on the type of bacterial infection and stage of the disease. Borrelia burgdorferi is one of the most common causes of Lyme disease symptoms.

Borrelia mayonii, a rare cause of Lyme disease in the upper Midwest, causes fever, headache, neck pain, rash, and arthritis pain in the late stages. Unlike B. burgdorferi, which typically causes a bulls-eye rash, B. mayonii often causes large rashes, nausea, and vomiting.

What Causes Lyme Disease?

Two types of bacteria—B. burgdorferi and B. mayonii—cause Lyme disease in the United States. Two other species, Borrelia afzelii, and Borrelia garinii are the primary culprits in Europe and Asia.

For a long time, scientists consider B. burgdorferi to be the sole cause of Lyme disease in the United States. Then, in 2013, scientists confirmed the existence of B. mayonii, linked to nausea and vomiting, in addition to the other typical symptoms.

Typically, ticks become infected when they feed on small animals, such as rodents. Blacklegged ticks primarily spread B. burgdorferi in the Northeast, North Central states, and mid-Atlantic. B. mayonii spreads in the upper Midwest. Specifically, the western blacklegged tick spreads B. burgdorferi on the Pacific coast.

Lyme disease spreads through the bite of an infected blacklegged tick. You will likely find blacklegged ticks in grassy and wooded areas, usually in low-lying vegetation like shrubs or grass. Ticks can attach to the skin if you brush up against those areas.

Ticks can latch on to any body part but frequently hide in areas like the scalp, armpits, or groin. Nymphs, immature ticks, often infect humans, usually in the spring or summer months. Adult ticks can spread the infection, too, but they are bigger and easier to detect than nymphs.  

Having a tick bite does not mean you will get Lyme disease. It can take 36 to 48 hours for transmission to occur.

Risk Factors

Anyone can develop Lyme disease. Still, some people have a higher risk than others, such as:

  • People who work outdoors (e.g., construction workers, landscapers, and park and wildlife managers)
  • People who live in the Northeastern and North Central regions of the United States
  • People who walk near woods, bushes, high grass, or leaves

Is Lyme Disease Contagious?

You cannot catch Lyme disease from other people. No evidence suggests that kissing, touching, or having sex with someone with Lyme disease puts you at risk. Likewise, Lyme disease does not spread through breast milk or blood. Still, the bacteria can live in blood, so experts advise people with Lyme disease not to donate blood.

Dogs can develop Lyme disease, but people cannot catch the illness from their pets. Although, cuddling with your furry friend could expose you to ticks attached to them.

How Is Lyme Disease Diagnosed?

Usually, healthcare providers diagnose Lyme disease based on symptoms and a patient's possible exposure to the blacklegged tick. Without the classic "bulls-eye" rash, other symptoms, such as fever, headache, and fatigue, are not specific. In other words, healthcare providers may have difficulty pinpointing the cause.

A healthcare provider may ask whether you've spent time outdoors in certain parts of the country, particularly during summer. They can perform lab tests to confirm the diagnosis.

Still, there's no quick-and-easy Lyme disease test. The CDC recommends a two-step blood test. The first step is an enzyme immunoassay (e.g., an enzyme-linked immunosorbent assay, or ELISA test). Or, a healthcare provider may use an immunofluorescence assay. A second antibody test, a Western blot test, can confirm Lyme disease if your initial test is positive.

Initial testing may not provide a positive reading even if you are infected. A healthcare provider may decide to start you on antibiotic treatment if you show symptoms of Lyme disease. 

A healthcare provider may look for evidence of antibodies against the bacteria that cause Lyme disease if you do not know if a tick has bitten you. Although, it can take several weeks to develop those antibodies.

Treatments for Lyme Disease

Lyme disease is curable with early diagnosis and prompt treatment. See a healthcare provider right away if you think a tick has bitten you. The sooner you start a course of antibiotics, the better. Many people respond well to treatment even when there's a lag in diagnosing the condition.

Antibiotics treat early Lyme disease symptoms. Usually, first-line treatment consists of a two- to four-week course of an oral antibiotic, such as amoxicillin, doxycycline, or cefuroxime axetil. You may take Advil or Motrin (ibuprofen) to ease inflammation, reduce fever, and alleviate pain.

People with Lyme disease and heart or nervous system concerns may require a course of intravenous (IV) antibiotics, such as ceftriaxone or penicillin.

See a healthcare provider right away if you are pregnant and suspect Lyme disease. Appropriate antibiotic treatment can prevent adverse side effects on the fetus and prevent complications.

Lyme Disease in Children and Dogs

Children with Lyme disease may require different treatment than adults. Dogs can also get Lyme disease, but their symptoms may present differently than humans.


Depending on where they live and play and how much time they spend outdoors, children may have a higher risk of Lyme disease than adults.

Parents may suspect Lyme disease if the family lives in or visits an area where the ticks are commonly found. Another indicator is knowing or suspecting your child has been exposed to ticks. Contact a healthcare provider if your child has a "bulls-eye" rash or other Lyme disease symptoms.

Children with Lyme disease typically receive two to four weeks of antibiotics. Common antibiotics include doxycycline or amoxicillin unless children are younger than 8 or have allergies.


Lyme disease shows up differently in pets than in people. 

Common Lyme disease symptoms in dogs include fever, loss of appetite, joint swelling, and decreased activity. Unlike many people, dogs do not develop a "bulls-eye" rash. Symptoms may only appear in your pet seven to 21 days or longer after infection.

Talk to a veterinarian if you suspect that your dog has Lyme disease. Treatment may include a few weeks of antibiotic therapy. 

You can help protect your dog by taking preventive measures. Inspect your dog daily for ticks, use flea and tick repellents, and keep your yard landscaped to reduce exposure. Use tweezers to remove any ticks on your dog's fur carefully.

How To Prevent Lyme Disease

To prevent Lyme disease, take the proper precautions to avoid tick bites, such as:

  • Check yourself, as well as your children and pets, for ticks after being outside. Pay particular attention to the hair, armpits, groin, and knees. 
  • Shower after being outside.
  • Stay in the center of trails or paths, and avoid tick-infested vegetation on the margins. 
  • To keep ticks at bay at home, trim brush, mow grass, and rake leaves on your property.
  • Toss clothing in the dryer and spin on high heat for at least 10 minutes to kill any ticks that may have stowed away on your clothing. 
  • Use insect repellant containing DEET. Spray your clothing, too, or wear clothing treated with permethrin, an insecticide. 
  • Wear long pants tucked into socks or boots and long sleeves. 
  • When walking or hiking, wear light-colored clothes to spot ticks that may land on you.

Be aware that blacklegged ticks thrive in humid, wooded habitats, particularly in low-lying grass and brush. The Northeast, upper Midwest, mid-Atlantic, and the Pacific coast are hot spots for Lyme disease.

How To Remove Ticks

Do not panic if you find a tick. You need to remove ticks quickly but carefully since crushing the tick may cause transmission of bacteria.

The CDC advises the following steps to remove ticks:

  • Use a pair of fine-pointed tweezers.
  • Grasp the tick at its attachment point, as close to the skin's surface as possible. Then, pull upward. Twisting or jerking it could leave parts of the tick behind. 
  • Wash your hands and clean the affected area with alcohol or soap and water. 
  • Dispose of the live tick by placing it in alcohol, sealing it in a plastic bag or container, wrapping it in tape, or flushing it down the toilet.

Lyme disease risk decreases if you remove the tick within 24 hours. See a healthcare provider if you develop a fever or rash within weeks of a tick bite.

There are many folk remedies for tick removal. For example, some suggest burning it with the end of a hot match or cigarette; smothering it with nail polish, alcohol, or petroleum jelly; or freezing it with ice. The CDC does not suggest any of those methods. The tick may burrow deep into the skin, boosting Lyme disease risk.


Even after being treated for Lyme disease, some people report post-treatment Lyme disease syndrome (PTLDS). PTLDS causes symptoms like lingering fatigue, pain, or joint and muscle aches. It's unclear what causes PTLDS, sometimes called chronic Lyme disease.

PTLDS is different from Lyme arthritis, which results from untreated Lyme disease that causes inflammatory arthritis. Often, Lyme arthritis affects the hips or knees. Healthcare providers can treat Lyme arthritis with antibiotics.

In contrast, some evidence suggests that extended antibiotic treatment does not help people with PTLDS recover. Instead, healthcare providers treat PTLDS similarly to fibromyalgia or chronic fatigue syndrome. Mostly, symptoms improve with time. In a small percentage of people, symptoms last more than six months.

If untreated, new and severe symptoms may develop days or months after infection. Those symptoms include additional rashes on other body parts or arthritis with severe joint pain or swelling. In severe cases, facial paralysis or neurological problems can occur.

A Quick Review

Lyme disease is a tick-borne illness that spreads through the bite of infected blacklegged ticks. Lyme disease causes flu-like symptoms and, in some cases, a "bulls-eye" rash. For the most part, symptoms subside with antibiotics. 

Consult a healthcare provider right away if you suspect Lyme disease. If untreated, people with Lyme disease can develop severe symptoms or complications. 

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