Lyme Disease | Symptoms & Causes

What are the symptoms of Lyme disease?

The list of possible symptoms for Lyme disease is long, and symptoms can affect every part of the body. Symptoms usually begin to appear within three to 30 days, and each child may experience them differently.

Stage 1 (between 3  to 30 days after the bite)

Around 70 to 80 percent of children with Lyme disease develop a rash that is pink in the center and a deeper red on the surrounding skin. Its scientific name is erythema migrans, and it’s also sometimes called a “bull’s eye rash.” This rash:

  • usually appears within 7 to 14 days of infection, but may not appear at all
  • expands over the course of days or weeks, if left untreated
  • may not resemble a bull’s eye, but instead just look red
  • is usually flat
  • may be very small or very large (up to 12 inches across)
  • may be mistaken for such skin problems as hives, eczema, sunburn, poison ivy and flea bites
  • may itch or feel hot, or not be felt at all
  • is rarely painful

Also, your child may show some flu-like symptoms, such as:

  • headache
  • stiff neck
  • aches and pains in muscles and joints
  • low-grade fever and chills
  • fatigue
  • poor appetite
  • sore throat
  • swollen glands

Stage 2 (weeks to months after the bite)

If your child has Lyme disease that has gone undiagnosed and untreated, the bacteria may enter her bloodstream and travel to other tissues in her body. After a few weeks to months, she may show signs and symptoms including: 

  • multiple erythema migrans rashes
  • facial nerve palsy, or loss of muscle tone in the face
  • lymphocytic meningitis
  • carditis (inflammation of the heart), resulting in disrupted electrical conduction in the heart (“heart block”)
  • flu-like symptoms similar to those found in Stage 1

Stage 3 (after several months to years)

By far, the most common late-stage symptom of Lyme disease is arthritis, particularly in the large joints, especially the knee. Typically, the joints will be more swollen and tender than painful, and anti-inflammatory medicine can help. 

The arthritis usually lasts for several weeks before getting better, and then reappearing in a different joint.  In the vast majority of cases, the arthritis eventually goes away on its own.

What causes Lyme disease?

Lyme disease is caused when one of several types of tiny black tick bites a human, injecting a bacterium into the skin. It cannot be spread from human to human.

There are three main bacteria that can cause Lyme disease, but only one of them, Borrelia burgdorferi, is found in the U.S. The other two are found in Europe and Asia, and people infected with them may show different symptoms.