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What is Lyme Disease - Early signs and symptoms


What is Lyme Disease - Early signs and symptoms

Lyme disease or Lyme borreliosis is the most common tick-borne infectious disease.

When a person gets infected, the bacteria travel through the bloodstream and affect various parts of the body. If left untreated, Lyme disease causes long-term infection characterized by inflammatory conditions, affecting multiple systems, such as the skin, joints, heart, and nervous system.

Lyme disease can affect anyone who has been bitten by an infected tick. It is the most common tick-borne illness in Europe and the United States. Treatment with antibiotics usually cures Lyme disease, especially when started early.


Cause of Lyme disease

Lyme disease is caused by a spirochete, (a flexible, spirally twisted bacterium) Borrelia burgdorferi (B burgdorferi). It is transmitted to humans through tick bites by infected pinhead-sized, black-legged ticks or deer ticks of the genus Ixodes.

Ticks pick up the bacteria after feeding on deer, birds, or mice with B burgdorferi infection.

Transmission of Lyme disease

These infected black-legged ticks can attach themselves to any part of the body but often latch onto hard-to-see areas, such as the scalp, groin, and armpit.

The infected adult or nymph tick bores a tiny hole on the skin, inserts its mouth into the opening, and attaches itself to the host. Typically, the tick must be attached to the body for at least 36 to 48 hours or more to pass on the bacteria to humans.

Larger adult ticks may be noticeable and can be removed. However, young nymph ticks may not be noticeable and remain undetected.


Risk factors for Lyme disease

Anyone can get a tick bite. Most tick bites happen in the summer months when ticks are most active, and people spend more time outdoors in areas where Lyme disease is common.

People at a higher risk of tick exposure are more likely to get this illness.  The risk of Lyme disease increases for:

  • People who spend lots of time doing outdoor activities, such as camping, walking, hunting, or hiking in grassy, wooded areas.
  • People who work in gardens and parks.
  • People who have pets or domesticated animals that visit wooded areas.


Three stages of Lyme disease

Stage 1: Early localized Lyme disease

Early localized infection occurs when the infection has not yet spread throughout the body. Only the site where the bacteria had first come in contact is affected.

Stage 2: Early disseminated Lyme disease

Within a few days to weeks after the onset of local infection, bacteria begin to spread throughout the body through the lymphatic system or bloodstream affecting different parts of the body.

Stage 3: Late disseminated Lyme disease

The bacteria have spread throughout the body.  After several months or years after the bite, untreated or inadequately treated Lyme disease affects many parts of the body, including the nerves, brain, eyes, joints and heart.


Signs and Symptoms of Lyme disease

The symptoms of Lyme disease vary in severity in people. Although Lyme disease may progress through three stages, the symptoms can overlap. Some people may present later-stage symptoms without having symptoms of early Lyme disease.

Symptoms of stage 1: Early localized Lyme disease

Early symptoms of Lyme disease begin between 3 and 30 days after an infected tick bite. 

A red rash called erythema migrans (EM)

About 70 to 80 percent of people with Lyme disease develop the EM rash often in the armpit, groin, back of the knee, on the trunk, or in children's hair, ears, or neck. The rash is usually circular or oval and gets bigger over several days ultimately reaching a diameter of about 12 inches.

The rash may feel warm to touch, is usually neither itchy nor painful, and takes up to four weeks or longer to resolve without treatment. As it starts to get better, it gradually loses its color in the center, forming a bulls-eye appearance.

Flu-like symptoms

About 50 percent of people who have Lyme disease develop symptoms similar to flu, such as:

  • Fever
  • Chills
  • A general feeling of being ill
  • Headache
  • Joint pain
  • Muscle pain
  • Stiff neck
  • Fatigue
  • Swollen lymph nodes near the site of the bite


Symptoms of stage 2: Early disseminated Lyme disease

A few weeks to months after the tick bite, untreated Lyme disease can lead to:

  • Several EM rashes at different sites on the body other than the original site of the tick bite
  • A fever
  • Arthritis that comes and goes
  • Muscle, tendon, and bone pains
  • Joint pains
  • Headaches
  • Neck stiffness
  • Painful inflammation of the brain and spinal cord (meningitis)
  • Numbness in arms or legs
  • Paralysis or weakness in the muscles of the face
  • Bell’s palsy (causes one half of the face to droop)
  • Heart problems, such as chest pains, slow or irregular heartbeat
  • Shortness of breath and dizzy spells
  • Mood changes
  • Memory problems


Symptoms of Stage 3: Late disseminated Lyme disease

Late disseminated Lyme disease can occur months or years after the infection mostly in people who did not get early treatment.

Lyme disease can cause long-term joint inflammation or Lyme arthritis, heart rhythm problems or Lyme carditis, and brain and nervous system problems. A person may have many symptoms of illness, including:

  • Muscle and joint pain
  • Joint swelling
  • Arthritis
  • Abnormal muscle movement
  • Muscle weakness
  • Shooting pains, numbness or tingling in the hands or feet
  • Speech problems
  • Thinking (cognitive) problems
  • Decreased concentration
  • Memory disorders
  • Nerve damage
  • Nerve pain
  • Dementia
  • Heart palpitations or an irregular heartbeat (Lyme carditis)
  • Heart failure
  • Bell’s palsy (loss of muscle tone or droop on one or both sides of the face)
  • Sleep disturbances
  • Vision problems


Diagnosis of Lyme disease

Lyme disease is diagnosed based on:

  • The symptoms
  • Full-body skin examination for erythema migrans (EM) rash
  • Physical findings, such as EM, facial or Bell’s palsy, or arthritis
  • History of exposure to infected black-legged ticks
  • Laboratory tests
    • The most used method for Lyme disease diagnosis is a two-stage blood test with enzyme-linked immunoassay (ELISA) and western blot. The primary test is the ELISA test that identifies certain antibodies produced by the immune system in response to Lyme disease infection. If the ELISA test is positive or equivocal, then a more specific western immunoblot test is done to confirm ELISA results.
  • Other tests that may be done when the infection has spread include:
    • Electrocardiogram
    • Echocardiogram
    • Magnetic resonance imaging (MRI) of the brain
    • Spinal tap