Lyme Disease Symptoms & Causes

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What is Lyme disease?

Lyme disease is an infection caused when one of several types of tiny black tick bites a human or other animal, injecting a bacterium. It’s not a chronic disease, and when discovered early, is easily treated with antibiotics; but left untreated, it can attack many systems of your child's body, including the skin, heart, nerves and joints.

The disease is transmitted to humans from contact with the tick—not spread from one human to another.

Will my child be OK?

When Lyme disease is caught early, the vast majority of children make a full recovery. Despite the fact that the disease occurs more often in children than adults, the neurological symptoms of late-stage Lyme disease appear to be rare in children.

What should I do if I find a tick on my child?

First, don't panic – two things are on your side:

  1. The risk of developing Lyme disease after being bitten by a tick is only about 1 percent to 3 percent.

  2. Ticks can’t transmit the bacteria that cause Lyme disease until they attach and begin to feed, which makes them engorged. This can take up to 48 hours, so if you find a tick that isn’t engorged, your child may be less likely to contract Lyme disease. The department of Epidemiology and Public Health at the Yale School of Medicine has a visual aid (.pdf) to help you determine how long a tick may have been attached.

All you need to do is to remove the tick and watch for symptoms. Here’s how:

Remove the tick

1. Remove the tick using a fine-tipped pair of tweezers. Grasp the body of the tick and pull in an upward motion until the tick comes out. Do not squeeze or twist the tick’s body.  Put the tick in a bottle.

2. Take note of the size and color of the tick, as well as your estimate of the time it has been attached and whether or not it is engorged.

3. It's not necessary to take your child to a doctor after a tick bite, but if you have questions or want a consult, see your child's pediatrician. In some cases, your child’s doctor may prescribe antibiotics to prevent Lyme disease from developing.

Watch for symptoms

1. If your child has been bitten by a tick, keep an eye out for a red, circular or oval-shaped rash that’s clear in the middle at the site of the bite (sometimes called a “bull’s eye rash”). Some children may have several of these rashes.

2. Other symptoms that could indicate Lyme disease include:

  • fever
  • headache
  • fatigue
  • muscle aches
  • joint aches

If your child develops any of these symptoms, call her pediatrician. If it turns out that your child has Lyme disease, a course of antibiotics typically resolves the illness.

How common is Lyme disease?

More and more cases of Lyme disease are being reported each year. According to the Center for Disease Control (CDC), about 30,000 people were infected in 2009 in the United States, where it accounts for more than 90 percent of all insect-borne illness.

Where do ticks carrying Lyme disease live?

These ticks are found in certain parts of the country (the Northeast and Mid-Atlantic states, the northern Midwest and the West Coast), and are often found on white-footed mice and white-tailed deer most commonly living in woods and high grass.

Why is it called Lyme disease?

The disease takes its name from Lyme, Connecticut, where the illness was first identified in the United States in 1975.

If you've had Lyme disease already, can you get it again?

Yes—humans do not develop immunity to Lyme disease, so re-infection is possible.


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 United States. The other two are found in Europe and Asia, and people infected with them may show different symptoms.


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 people 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.


Q: Will my child be OK?
Most likely. Caught early, the vast majority of children make a full recovery.

Q: Is Lyme disease contagious?
A: No, not from person-to-person. You can only get Lyme disease from being bitten from a tick that is carrying the bacteria.

Q: Can my child be diagnosed with Lyme disease if there’s no evidence of a tick bite?
Yes, many people with Lyme disease are diagnosed without any knowledge of a tick bite, if there’s a possibility that they may have been exposed to one of the bacteria-carrying ticks.

Q: Is there a vaccine for Lyme disease?
There used to be, but it was taken off the market in 2002. No vaccine for Lyme disease is currently available.

Q: Is Lyme disease chronic?
Doctors don’t believe that Lyme disease is chronic, but some children experience what’s called “post-infectious syndrome.” This is a condition that occurs after many bacterial and viral infections, including mononucleosis and hepatitis A.

There’s a wide range of symptoms that your child could experience from post-infectious syndrome, but some of the more common ones include:

  • feeling fatigued
  • weakness
  • joint aches and pains
  • shooting pains
  • headaches
  • difficulty sleeping
  • problems concentrating

Q: How is post-infectious syndrome treated?
Since post-infectious syndrome is not itself caused by an infectious agent (it follows an infection caused by an infectious agent), doctors generally don’t prescribe antibiotics. Most often, different treatment modalities are used, which may include:

  • keeping to a set sleep schedule
  • exercise
  • acupuncture
  • biofeedback
  • physical therapy
  • anti-inflammatory drugs to help with aches and pains

Q: How long does post-infectious syndrome last? 
Each child is different, but it’s not uncommon for symptoms of post-infectious syndrome to linger for months, or even years. They may seem to come and go, and can be influenced by stress or any other infections or illnesses your child experiences. But most children do make a full recovery.

Q: If you've had Lyme disease already, can you get it again?
Yes—humans do not develop immunity to Lyme disease, so re-infection is possible.


How can Lyme disease be prevented?

1. Regular tick checks

Check yourself and your family frequently for ticks, especially if you live or are traveling in an area where the ticks are common – even if you’ve only been out in your yard. Black-legged ticks can be extremely tiny, measuring less than one millimeter across, so make sure you search your child’s clothing and body very thoroughly. 

Since it takes about 48 hours for an infected tick to transmit Lyme disease, one thorough check per day is enough (and much better than several hasty checks). Remember to check:

  • all parts of the body that bend: behind the knees, between fingers and toes, underarms and groin
  • other areas where ticks are commonly found: belly button, in and behind the ears, neck, hairline and top of the head
  • hair – run a fine-toothed comb through to check for ticks
  • where underwear waistband touches the skin
  • where pants waistband touches the skin
  • anywhere else clothing presses on the skin

It’s also a good idea to visually check all other areas of your child's body and hair, and run fingers gently over skin.

2. Keep ticks away from skin.

  • Ticks can’t bite through clothes, so dress your family in: long-sleeved shirts tucked into pants
    • long pants with legs tucked into socks
    • socks and closed-toed shoes
    • light-colored clothing so any ticks are visible
    • Shower after all outdoor activities are over for the day. It may take four to six hours for ticks to attach firmly to skin. Showering will help remove unattached ticks.
  • Products that contain DEET are tick-repellent, but do not kill the tick and are not 100 percent effective. Use a brand of insect repellent that is designated as child-safe if your child is 1 year or older; for infants, check with your pediatrician about whether it’s ok to use repellent and if so, what brands he recommends.
  • Treat clothing with a product that contains permethrin, which is known to kill ticks on contact.

3. Try to avoid tick playgrounds.

  • Ticks like low-level shrubs and grasses, particularly at the edges of wooded areas. If you’re hiking, try to stay in the center of the trail and avoid bushwhacking.
  • Walk on cleared paths or pavement through wooded areas and fields when possible.

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