Lyme disease

Other Names: Borreliosis; Lyme borreliosis;Bannwarth syndrome

Lyme disease is a bacterial infection that is spread through the bite of one of several types of ticks.

Cause

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Lyme disease is caused by bacteria called Borrelia burgdorferi (B burgdorferi). Blacklegged ticks (also called deer ticks) can carry these bacteria. Not all species of ticks can carry these bacteria. Immature ticks are called nymphs, and they are about the size of a pinhead. Nymphs pick up bacteria when they feed on small rodents, such as mice, infected with B burgdorferi. You can get the disease if you are bitten by an infected tick.

Epidemiology

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Lyme disease was first reported in the United States in 1977 in the town of Old Lyme, Connecticut. The same disease occurs in many parts of Europe and Asia. In the United States, most Lyme disease infections occur in the following areas:

• Northeastern states, from Virginia to Maine
• North-central states, mostly in Wisconsin and Minnesota
• West Coast, mainly in the northwest

Riskfactors

• Doing outside activities that increase tick exposure (for example, gardening, hunting, or hiking) in an area where Lyme disease occurs
• Having a pet that may carry infected ticks home
• Walking in high grasses

Important facts about tick bites and Lyme disease:

• A tick must be attached to your body for 24 to 36 hours in order to spread the bacteria to your blood.
• Blacklegged ticks can be so small that they are almost impossible to see. Many people with Lyme disease never even see or feel a tick on their body.
• Most people who are bitten by a tick do not get Lyme disease.

Stages

There are three stages of Lyme disease. Stage 1 is called early localized Lyme disease. The bacteria have not yet spread throughout the body. Stage 2 is called early disseminated Lyme disease. The bacteria have begun to spread throughout the body. Stage 3 is called late disseminated Lyme disease. The bacteria have spread throughout the body.

Symptoms

Symptoms of early localized Lyme disease (stage 1) begin days or weeks after infection. They are similar to the flu and may include:

• Fever and chills
• General ill feeling
• Headache
• Joint pain
• Muscle pain
• Stiff neck

There may be a "bull's eye" rash, a flat or slightly raised red spot at the site of the tick bite. Often there is a clear area in the center. It can be large and expanding in size. This rash is called erythema migrans. Without treatment, it can last 4 weeks or longer. Symptoms may come and go. Untreated, the bacteria can spread to the brain, heart, and joints.

Symptoms of early disseminated Lyme disease (stage 2) may occur weeks to months after the tick bite, and may include:

• Numbness or pain in the nerve area
• Paralysis or weakness in the muscles of the face
• Heart problems, such as skipped heartbeats (palpitations), chest pain, or shortness of breath

Symptoms of late disseminated Lyme disease (stage 3) can occur months or years after the infection. The most common symptoms are muscle and joint pain. Other symptoms may include:

• Abnormal muscle movement
• Joint swelling
• Muscle weakness
• Numbness and tingling
• Speech problems
• Thinking (cognitive) problems

Diagnosis

A blood test can be done to check for antibodies to the bacteria that cause Lyme disease. The most commonly used is the ELISA for Lyme disease test. An immunoblot test is done to confirm ELISA results. Be aware, though, in the early stage of infection, blood tests may be normal. Also, if you are treated with antibiotics in the early stage, your body may not make enough antibodies to be detected by blood tests.

In areas where Lyme disease is more common, your health care provider may be able to diagnose early disseminated Lyme disease (Stage 2) without doing any lab tests.

Other tests that may be done when the infection has spread include:

• Electrocardiogram
• Echocardiogram to look at the heart
• MRI of the brain
• Spinal tap (lumbar puncture to examine spinal fluid)

Treatment

People bitten by a tick should be watched closely for at least 30 days to see if a rash or symptoms develop. A single dose of the antibiotic doxycycline may be given to someone soon after being bitten by a tick, when all of these conditions are true: The person has a tick that can carry Lyme disease attached to his or her body. This usually means that a nurse or doctor has looked at and identified the tick.

• The tick is thought to have been attached to the person for at least 36 hours.
• The person is able to start taking the antibiotic within 72 hours of removing the tick.
• The person is 8 years or older and is not pregnant or breastfeeding.
• Local rate of ticks carrying B burgdorferi is 20% or higher.

A 10-day to 4-week course of antibiotics is used to treat people who are diagnosed with Lyme disease, depending on the choice of drug: The choice of antibiotic depends on the stage of the disease and the symptoms. Common choices include doxycycline, amoxicillin, azithromycin, cefuroxime, and ceftriaxone. Pain medicines, such as ibuprofen, are sometimes prescribed for joint stiffness.

Prognosis

If diagnosed in the early stages, Lyme disease can be cured with antibiotics. Without treatment, complications involving the joints, heart, and nervous system can occur. But these symptoms are still treatable and curable. In rare cases, a person keeps having symptoms that interfere with daily life after they have been treated with antibiotics. This is also known as post-Lyme disease syndrome. The cause of this syndrome is unknown. Symptoms that occur after antibiotics are stopped may not be signs of active infection and may not respond to antibiotic treatment.

Lyme Disease FAQS

What is Lyme disease?

• Lyme disease is an infection caused by a kind of bacteria (germ) called a spirochete (say: "spy-ro-keet").

How is Lyme disease transmitted?

• The disease is carried by deer ticks and western black-legged ticks (found mostly on the Pacific Coast).
• These ticks can spread the disease to animals and humans through tick bites.
• These ticks are about the size of a sesame seed.
• Lyme disease is most common in rural and suburban areas in the northeastern and midwestern states.
• Lyme disease is also found in other parts of the United States, as well as in Europe, Asia and Australia.

What are the symptoms of Lyme disease?

• One sign of Lyme disease is a rash, which may appear 3 to 30 days after a tick bite.
• This rash, called erythema migrans (say: "ear-a-theem-a my-granz"), usually starts at the site of the tick bite.
• It may begin as a small red spot and grow larger.
• The center may fade, creating a "bull's eye" or ring appearance, but this is not always the case.
• Some people with Lyme disease have many red spots.
• The rash may burn, hurt or itch, or you may not feel it.
• Other symptoms of Lyme disease include fever, chills, headaches, stiff neck, fatigue, muscle aches and joint pain.

What about the later stages of Lyme disease?

• If Lyme disease isn't treated, it can spread to other parts of the body.
• The symptoms of late Lyme disease include arthritis (painful, swollen joints) and nervous system problems.
• Lyme arthritis often affects only one of the large joints, such as the knee.
• Sometimes it may affect more than one joint.
• The symptoms of the nervous system disorder caused by late Lyme disease may include trouble concentrating, loss of memory, muscle weakness, and tingling and numbness in the arms and legs.
• However, Lyme disease rarely causes such nervous system problems.

How can my doctor tell if I have Lyme disease?

• The best way to find out if you have Lyme disease is to talk to your family doctor about your symptoms.
• Blood tests aren't always necessary to make the diagnosis as they can sometimes give false results.

• How is Lyme disease treated?

• Lyme disease is treated with antibiotics.
• Early Lyme disease responds very well to treatment.

How can I prevent Lyme disease?

• The best way to prevent Lyme disease is to prevent tick bites.
• Wear light-colored clothing that covers most of your skin when you go into the woods or an area overgrown with grass and bushes.
• This makes it easier to see and remove ticks on your clothing. Wear a long-sleeved shirt and wear pants instead of shorts.
• Tuck your pant legs into your socks for added protection.
• Remember that ticks are usually found close to the ground, especially in moist, shaded areas.
• Use an insect repellent containing DEET or permethrin. Apply DEET sparingly to skin according to directions on the label.

What do I do if I find a tick on my skin?

• Don't panic.
• Using a pair of fine-tipped tweezers, grasp the tick body as close to your skin as possible.
• Pull in a steady upward motion until the tick comes out. Be careful not to squeeze or twist the tick body.
• If any tick parts remain in the skin, you can leave them alone or carefully remove them the same way you would a splinter.
• Then apply an antiseptic to the bite area and wash your hands with soap and water.
• Don't use the old methods of putting petroleum jelly, nail polish, kerosene, gasoline or matches on the tick to try to remove it.
• After the tick is removed, watch the bite area and the rest of your skin over the next month.
• If you get a rash, see your doctor.

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