All about Borrelia, Lyme Disease & Treatment

Lyme Disease (Tick-borne borreliosis, Lyme arthritis) Fact Sheet

All about Borrelia, Lyme Disease & Treatment

Lyme disease is an infection caused by the bacteria Borrelia burgdorferi and is spread to humans through the bite of infected blacklegged ticks (or deer ticks).

Not all deer ticks are infected with the bacteria. Lyme disease can affect people of any age. A vaccine for Lyme disease is not currently available.

Lyme disease is the most prevalent tick-borne disease in New York and has been reportable since 1986.

Who gets Lyme disease?

Lyme disease can affect people of any age. People who spend time outdoors in activities such as camping, hiking, golfing, or working or playing in grassy and wooded environments are at increased risk of exposure. The chances of being bitten by a deer tick are greater during times of the year when ticks are most active.

Ticks can be active any time the temperature is above 45° F. Young deer ticks, called nymphs, are active from mid-May to mid-August and are about the size of poppy seeds. Adult ticks are most active from March to mid-May and from mid-August to November and are about the size of sesame seeds. Both nymphs and adults can spread Lyme disease.

Infected deer ticks can be found throughout New York State.

How is Lyme disease spread?

Not all deer ticks are infected with the bacteria that cause Lyme disease. Ticks can become infected if they feed on animals such as mice and other mammals that are infected.

The disease can be spread when an infected tick bites a person and stays attached for a period of time. In general, the tick must be attached for 36 to 48 hours or more. Lyme disease does not spread from one person to another.

Transfer of the bacteria from an infected pregnant woman to her fetus is extremely rare.

What are the signs and symptoms of Lyme disease?

Early symptoms usually appear within 3 to 30 days after the bite of an infected tick. In 60-80 percent of cases, a circular bull's eye rash about two inches in diameter, called erythema migrans, appears and expands around or near the site of the tick bite. Sometimes, multiple rash sites appear.

One or more of the following symptoms usually mark the early stage of Lyme disease: chills and fever, headache, fatigue, stiff neck, muscle and/or joint pain, and swollen glands. If Lyme disease is unrecognized or untreated in the early stage, more severe symptoms may occur.

As the disease progresses, severe fatigue, a stiff aching neck, and tingling or numbness in the arms and legs, or facial paralysis can occur. The most severe symptoms of Lyme disease may not appear until weeks, months or years after the tick bite.

These can include severe headaches, painful arthritis, swelling of the joints, and heart and central nervous system problems.

How is Lyme disease diagnosed?

Symptoms and possible tick bite exposure may cause a health care provider to suspect Lyme disease. If suspected, lab tests can be performed to confirm diagnosis.

What is the treatment for Lyme disease?

Patients treated with antibiotics in the early stages of Lyme disease usually recover quickly and completely. Antibiotics commonly used for treatment include doxycycline, amoxicillin, or cefuroxime axetil.

Patients with certain neurologic or cardiac forms of illness may require additional treatment. It is important to speak with your health care provider if you think you might have Lyme disease.

The best treatment for Lyme disease is prevention and awareness.

Does past infection with Lyme disease make a person immune?

Lyme disease is a bacterial infection. Even if successfully treated, a person may become re-infected if bitten later by another infected tick.

What can be done to prevent Lyme disease?

The best prevention of Lyme disease is through awareness. Generally, ticks cannot jump or fly onto a person. They wait in vegetation and cling to animals and humans when they brush by.

When in a potentially tick-infested habitat (wooded and grassy areas) take special care to prevent tick bites, such as wearing light-colored clothing (for easy tick discovery) and tucking pants into socks and shirt into pants.

Check after every 2 to 3 hours of outdoor activity for ticks on clothing or skin. Brush off any ticks on clothing or skin before skin attachment occurs. A thorough check of body surfaces for attached ticks should be done at the end of the day.

If removal of attached ticks occurs within 36 hours, the risk of tick-borne infection is minimal. For proper tick removal, please watch the video at Tick removal. A vaccine for Lyme disease is not currently available.

Insect repellents can be effective at reducing bites from ticks that can spread disease. If you decide to use a repellent, use only what and how much you need for your situation. More information on repellents can be found at Environmental Protection Agency – insect-repellents.

In addition:

  • Be sure to follow label directions.
  • Try to reduce the use of repellents by dressing in long sleeves and pants tucked into socks or boots.
  • Children should only handle repellents with adult supervision. Adults should apply repellents to their own hands first and then gently spread on the child's exposed skin. Avoid applying directly to children's hands. After returning indoors, wash your child's treated skin and clothing with soap and water or give the child a bath.
  • Do not apply near eyes, nose or mouth and use sparingly around ears.
  • After returning indoors, wash treated skin with soap and water.

Domestic animals can carry ticks into areas where you live so it is important to check pets for ticks before they enter the home.

How should a tick be removed?

Grasp the mouthparts with tweezers as close as possible to the attachment (skin) site. Be careful not to squeeze, crush or puncture the body of the tick, which may contain infectious fluids. Pull firmly and steadily upward to remove the tick. After removing the tick, thoroughly disinfect the bite site and wash hands.

The NYSDOH has created a video on proper tick removal (Proper Tick removal) and a printable card with steps on how to remove ticks (How to Remove a Tick Card). See or call a doctor if there are concerns about incomplete tick removal.

Do not attempt to remove ticks by using petroleum jelly, lit cigarettes or other home remedies because these may actually increase the chance of contracting a tick-borne disease.

Actual size of a tick


Lyme Disease: Symptoms, Causes, Diagnosis, Treatment, Prevention

All about Borrelia, Lyme Disease & Treatment

Editor's note: This article was updated on August 6, 2018.

The black-legged tick is on the move.

Cases of Lyme disease — traditionally more prevalent in the Northeast — have now been found in all 50 states and the District of Columbia, a new study from Quest Diagnostics found. While the Northeast still reported the highest number of cases, California and Florida had the highest percentage increase in positive test results from 2015 to 2017.

Experts say the tick has been expanding its range into the southern and western U.S. and into Canada, making it ly that the number of Lyme disease cases in North America will climb. A recent CDC study found that cases of Lyme increased more than 80% between 2004 and 2016 — from 19,804 to 36,429.

Those are the reported cases. The CDC estimates there are more than 300,000 cases of Lyme infection in the U.S. each year — or 10 times as many as what is reported.

“There's obviously year-to-year bouncing around, but the trend line is upward,” says John Aucott, MD, director of the Johns Hopkins Lyme Disease Clinical Research Center in Baltimore. “It won't stop in the foreseeable future.”

Most cases are clustered in 14 states in the Northeast and Upper Midwest, but Lyme has been reported as far south as Mexico, and increasingly, in Canada.

The black-legged tick (Ixodes scapularis), also known as the deer tick, carries the bacteria that causes Lyme infection. The same tick also can spread other diseases, including babesiosis, anaplasmosis, and Powassan virus — other diseases on the rise in the U.S.

Here's more about the disease and what to expect this year and beyond.

Lyme disease is caused by bacteria, Borrelia burgdorferi that are transmitted to humans through a bite from an infected black-legged or deer tick. Symptoms can occur anywhere from 3 to 30 days after the bite and can be wide-ranging, depending on the stage of the infection. In some cases, symptoms can appear months after the bite.

The chances you might get Lyme disease from a tick bite depend on the kind of tick, where you were when the bite occurred, and how long the tick was attached to you, the CDC says.

Black-legged ticks must be attached to you for 36 to 48 hours to transmit Lyme disease.

If you remove the tick or ticks within 48 hours, you aren't ly to get infected, says Cleveland Clinic infectious disease specialist Alan Taege, MD.

Early signs and symptoms include fever, chills, headache, fatigue, muscle and joint pain, and swollen lymph nodes — all common in the flu. In up to 80% of Lyme infections, a rash is one of the first symptoms, Aucott says.

Without treatment, symptoms can progress. They might include:

  • Severe headache or neck stiffness
  • Rashes on other areas of the body
  • Arthritis with severe joint pain and swelling, particularly in the knees
  • Loss of muscle tone or “drooping” on one or both sides of the face.
  • Heart palpitation or an irregular heartbeat
  • Inflammation of the brain and spinal cord
  • Shooting pains, numbness, or tingling in the hands or feet

About 20% to 30% of Lyme rashes have a “bull's-eye” appearance — concentric circles around a center point — but most are round and uniformly red and at least 5 centimeters (about 2 inches) across, Aucott says.

“Most are just red,” he says. “They do not have the classic ring within a ring the Target logo.”

The rash expands gradually over a period of days and can grow to about 12 inches across, the CDC says. It may feel warm to the touch, but it rarely itches or is painful, and it can appear on any part of the body.

TIcks come in three sizes, depending on their stage of life. Larvae are the size of grains of sand, nymphs the size of poppy seeds, and adults the size of an apple seed. 

Doctors diagnose it symptoms and a history of tick exposure. Two-step blood tests are helpful if used correctly. But the accuracy of the test depends on when you got infected. In the first few weeks of infection, the test may be negative, as antibodies take a few weeks to develop. Tests aren't recommended for patients who don't have Lyme disease symptoms.

Aucott says the most promising development in the fight against Lyme disease are better diagnostic tests that are accurate in the first few weeks after exposure. The earlier the treatment, the less ly the disease will progress. Aucott says he expects the tests to be available soon.

Doctors may not recognize symptoms, especially those who practice in areas where Lyme infection isn't prevalent, and up to 30% of the infections are not accompanied by a rash.

There are three stages:

  • Early localized Lyme: Flu- symptoms such as fever, chills, headache, swollen lymph nodes, sore throat, and typically a rash that has a “bull's-eye” appearance or is uniformly round and red and at least 5 centimeters in size
  • Early disseminated Lyme: Flu- symptoms that now include pain, weakness, or numbness in the arms and legs, vision changes, heart palpitations and chest pain, a rash, and facial paralysis (Bell's palsy)
  • Late disseminated Lyme: This can occur weeks, months, or years after the tick bite. Symptoms might include arthritis, severe fatigue and headaches, vertigo, sleep disturbances, and mental confusion.

While experts don't understand it, roughly 10% of people treated for Lyme infection do not shake the disease.

They may go on to have three core symptoms — joint or muscle pain, fatigue, and short-term memory loss or mental confusion This is called post-treatment Lyme disease syndrome.

It's considered controversial because its symptoms are shared with other diseases and there isn't a blood test to diagnose it, Aucott says.

There are theories as to why Lyme symptoms become chronic. One is that the body continues fighting the infection long after the bacteria are gone, much an autoimmune disorder.

Antibiotics are used to treat early stage Lyme infection. Patients typically take doxycycline for 10 days to 3 weeks, or amoxicillin and cefuroxime for 2 to 3 weeks. In

up to 90% of cases, the antibiotic cures the infection. If it doesn't, patients might get other antibiotics either by mouth or intravenously.

For early disseminated Lyme disease, which may happen when a Lyme infection goes untreated, oral antibiotics are recommended for symptoms such as facial palsy and abnormal heart rhythm. Intravenous antibiotics are recommended if a person has meningitis, inflammation of the lining of the brain and spinal cord, or more severe heart problems.

In late-stage Lyme, a patient may receive oral or intravenous antibiotics. Patients with lingering arthritis would receive standard arthritis treatment.

There is no treatment for post-treatment Lyme disease syndrome.

“Ten percent of people don't get better after antibiotics,” Aucott says. “We think it's very significant if 30,000 people a year don't get better.”

Mainly New England, the Mid-Atlantic states, and part of the Upper Midwest.

The CDC says 95% of confirmed cases in 2016 were in 14 states: Connecticut, Delaware, Maine, Maryland, Massachusetts, Minnesota, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, Virginia, and Wisconsin. From 2006 to 2016, case numbers have increased in Ohio, Indiana, and Michigan as the tick's range expands westward.

In 2016, the highest number of confirmed Lyme infection cases — 9,000 — was reported in Pennsylvania, followed by New Jersey, with more than 3,300 cases.

In the Southern U.S., which is more prone to hot weather, ticks tend to stay under leaf litter and don't come up higher to feed much, Aucott says — “ticks don't to dry out.” This means Southern ticks don't transmit Lyme as frequently because they don't tend to feed on humans.

Infection is more common in males up to age 15 and between the ages of 40 and 60, says Taege. “These are people who are more ly to play outside, and go camping, hunting, and hiking,” he says.

Aucott adds that Lyme infection drops off in older teens and those in their 20s “because they're inside on their computers.” Older adults, he says, tend to have more time to work in their backyards, which is where most Lyme infection is transmitted.

Scientists point to a variety of causes for the spread of Lyme infection. Among them are reforestation, especially in the Northeast U.S., where Lyme disease is more prevalent; climate change and temperature extremes; suburbanization; and more exposure to the white-tailed deer, which is the black-legged tick's favorite mode of travel.

Development led to record low numbers of deer early in the last century, says CDC epidemiologist Paul Mead, MD. But the deer population has rebounded as reforestation took place over several decades, meaning the tick population has risen and expanded as well.

“Ticks have a pretty long life cycle, lasting 2-3 years, and typically don't move very far within their lifetime, so it takes a while to see large changes,” he says.

Deer and white-footed mice, which transmit Lyme disease to ticks that bite them, are moving closer to humans as their habitats disappear, says Taege. Ticks don't mind dogs, either, which carry them into homes and spread them to their humans.

Another reason: Warmer weather and mild winters may bring more people outside, raising their chances of being bitten, particularly in Lyme-prone areas, Taege says.

“Whether you believe in global warming or not, we have longer, warmer summer months, and people are outdoors more,” says Taege. “We've seen an expansion [of ticks] in areas in which the vectors live, and we've slowly seen more Lyme disease.”

That doesn't mean you should be afraid of outdoor activities, as long as you take precautions to avoid tick bites, Aucott says.

Ticks can't fly or jump, but instead live in shrubs and bushes, and grab onto someone when they pass by. To avoid getting bitten:

  • Wear pants and socks in the woods, areas with lots of trees, and while handling fallen leaves
  • Wear a tick repellent on your skin and clothing that has DEET, lemon oil, or eucalyptus.
  • For even more protection, use the chemical permethrin on clothing and camping gear.
  • Shower within 2 hours after coming inside, if possible.
  • Look at your skin and wash ticks your hair.
  • Put your clothing and any exposed gear into a hot dryer to kill whatever pests might remain.

Given that the ticks are the size of a poppy seed, you've got to have pretty good eyes. The CDC recommends that if you've been walking in the woods, in tall grass, or working in the garden, check your skin afterward, ideally in the shower or bath. That way, you've removed your clothes, which may carry ticks, too.

Remove it with a pair of fine-tipped tweezers as soon as possible, pulling upward with steady pressure. If parts of the tick remain in the skin, also try to remove them with the tweezers. After everything is out, clean the bite area with rubbing alcohol or soap and water.

Mead says you're not ly to get infected if you remove the tick within 36 to 48 hours.

Some people have an allergic reaction to ticks, so they'll notice a bite right away.

Place it in soapy water or alcohol, stick it to a piece of tape, or flush it down the toilet.

The rash is a pretty good indication that you may have been bitten. Take a photo of the rash and see your doctor, Aucott says. At this stage of the illness, treatment with antibiotics will probably be successful.

If you don't have the telltale rash but have a summer flu — fatigue, fever, headache but no respiratory symptoms a cough — you may want to talk to your doctor, Aucott says.

The FDA in July 2017 gave “fast-track” approval to French biotech company Valneva to test potential Lyme disease vaccine VLA15 on adults in the U.S. and Europe. Data from the first phase are expected to be released soon, and then the second phase will begin.

The more ticks in your region, the lier it is that your furry pal will bring them home. Mead says.

Dogs are much more ly than humans to be bitten by ticks, and where Lyme disease is more prevalent, up to 25% of dogs have evidence of past infection, he says.

“On the flip side, low rates of exposure in dogs is a good indicator that Lyme is not a problem in the area.”

And they can get sick. About 10% of dogs with Lyme disease will become ill. Common symptoms, which may show up 7-21 days after a tick bite, are lameness — your dog will appear to be walking on eggshells — a fever, lethargy, and enlarged lymph nodes. Dogs also get antibiotics for treatment.

Practice prevention habits and use a tick control product on your pet.A Lyme vaccine is also available for dogs.


John Aucott, MD, assistant professor of medicine, Johns Hopkins University School of Medicine; director, Johns Hopkins Lyme Disease Clinical Research Center.


Morbidity and Mortality Weekly Report: “Vital Signs: Trends in Reported Vectorborne Disease Cases — United States and Territories, 2004-2016.”

Alan Taege, MD, department of infectious disease, Cleveland Clinic.

EPA: “Climate Change Indicators in the United States.”

American College of Rheumatology.

Infectious Diseases Society of America.

Eisen, R. J Med Entomol, March 2016.

Paul Mead, MD, chief of epidemiology and surveillance activity, Bacterial Diseases Branch, CDC.

Valneva SE.

MSPCA-Angell: “Lyme Disease in Dogs.”

VCA Hospitals: “Lyme Disease in Dogs.”

UpToDate: “Lyme Disease Treatment.”

Global Lyme Alliance.

Entomology Today, Sept. 28, 2017.

U.S. Global Change Research Program: “Climate and Health Assessment.”

Government of Canada: “Surveillance of Lyme disease.”

American Lyme Disease Foundation.

TickEncounter Resource Center: “Top 10 Things Everyone Should Know About Ticks These Days.”

Quest Diagnostics: “Lyme Disease Health Trends.”

© 2018 WebMD, LLC. All rights reserved.


Borrelia mayonii | CDC

All about Borrelia, Lyme Disease & Treatment

Borrelia mayonii are a type of bacteria recently found in North America that can cause Lyme disease.  These bacteria are different from the three types of bacteria that cause most cases of Lyme disease worldwide.

  • Borrelia burgdorferi (North America, Europe)
  • B. afzelii (Europe, Asia)
  • B. garinii (Europe, Asia)

B. mayonii is the only species besides B. burgdorferi shown to cause Lyme disease in North America.

How was it discovered?

In 2013, scientists at the Mayo Clinic noticed an unusual result while testing blood from patients who were thought to have Lyme disease. Cooperation between Mayo Clinic, state public health agencies, and CDC confirmed that a new type of bacteria that infects people had been found in blacklegged ticks.

Where does B. mayonii occur?

Current evidence suggests that within the United States, B. mayonii is only found in the Upper Midwest.

Has B. mayonii been found in ticks?

Yes, but not as often as B. burgdorferi. B. mayonii has been found in blacklegged ticks collected in northwestern Wisconsin and Minnesota. The blacklegged tick can also transmit B. burgdorferi (the bacteria that causes almost all Lyme disease infections in the United States), and the germs that cause anaplasmosis, babesiosis, and Powassan virus disease.

What type of illness does B. mayonii cause?

limited information, illness caused by B. mayonii appears similar to that caused by B. burgdorferi, but with a few differences. B. burgdorferi, B.

mayonii causes fever, headache, rash, and neck pain in the days after infection and can cause arthritis after a few weeks of illness. Un B. burgdorferi, B.

mayonii can also cause nausea and vomiting; large, widespread rashes; and a higher concentration of bacteria in the blood.

What tests are used to diagnose B. mayonii?

Your healthcare provider may order a blood test to look for infection. Limited available information suggests that patients with B. mayonii infection develop antibodies that are similar to those of patients infected with B. burgdorferi. Therefore, Lyme disease serologic testing may help in diagnosing patients with B. mayonii. In some cases, B.

mayonii bacteria may also be seen on a blood smear. Infection with B. mayonii can be specifically identified by Lyme disease molecular tests at Mayo Clinic. Lyme disease, including infection with B.

mayonii, can be diagnosed without testing when patients have signs and symptoms consistent with Lyme disease and a history of possible exposure to blacklegged ticks.

How is B. mayonii treated?

Physicians have successfully treated patients infected with B. mayonii with a 2- to- 4-week course of doxycycline. Other antibiotics that are often used to successfully treat Lyme disease can also be used.

Why are we just discovering this now?

It is possible that the bacteria recently emerged or that the bacteria have been present in the area for a long time but hadn’t been discovered. Mayo Clinic tested roughly 100,000 patient samples in the same way for over a decade but only recently detected B. mayonii.

I live in the northeastern United States where Lyme disease is common. Should I be worried about B. mayonii?

At this time, there is no evidence that B. mayonii is found outside of the Upper Midwest. However, you should continue to take precautions against tick bites as Lyme disease, anaplasmosis, and babesiosis are common in much of the Northeast.

What more do researchers need to know?

CDC, Mayo Clinic, and the Minnesota Department of Health continue to test blood samples from patients suspected of tickborne illness, Lyme disease, to learn more about tickborne bacteria that may cause human illness.

In addition, biologists continue to collect and test ticks throughout the United States to determine the range of the ticks that are infected with these bacteria.

How can I avoid this disease?

For more information, see Preventing Tick Bites.


Potential treatment for Lyme disease kills bacteria that may cause lingering symptoms, study finds

All about Borrelia, Lyme Disease & Treatment

Screening thousands of drugs, Stanford scientists determined that in mice, azlocillin, an antibiotic approved by the Food and Drug Administration, eliminated the bacteria that causes Lyme disease.

For decades, the routine treatment for Lyme disease has been standard antibiotics, which usually kill off the infection. But for up to 20% of people with the tick-borne illness, the antibiotics don’t work, and lingering symptoms of muscle pain, fatigue and cognitive impairment can continue for years — sometimes indefinitely.

A new Stanford Medicine study in lab dishes and mice provides evidence that the drug azlocillin completely kills off the disease-causing bacteria Borrelia burgdorferi at the onset of the illness. The study suggests it could also be effective for treating patients infected with drug-tolerant bacteria that may cause lingering symptoms.

“This compound is just amazing,” said Jayakumar Rajadas, PhD, assistant professor of medicine and director of the Biomaterials and Advanced Drug Delivery Laboratory at the Stanford School of Medicine.

“It clears the infection without a lot of side effects. We are hoping to repurpose it as an oral treatment for Lyme disease.” Rajadas is the senior author of the study, which was published online March 2 in Scientific Reports.

The lead author is research associate Venkata Raveendra Pothineni, PhD.

“We have been screening potential drugs for six years,” Pothineni said. “We’ve screened almost 8,000 chemical compounds. We have tested 50 molecules in the dish.

The most effective and safest molecules were tested in animal models. Along the way, I’ve met many people suffering with this horrible, lingering disease.

Our main goal is to find the best compound for treating patients and stop this disease.”

Hunting for alternative drug

Frustrated by the lack of treatment options for Lyme disease patients with lingering symptoms, Rajadas and his team began hunting for a better alternative in 2011.

 In 2016, they published a study in Drug Design, Development and Therapy that listed 20 chemical compounds, from about 4,000, that were most effective at killing the infection in mice.

All 20 had been approved by the Food and Drug Administration for various uses. One, for instance, is used to treat alcohol abuse disorder. 

In this most recent study, azlocillin, one of the top-20 contenders, was shown to eclipse a total of 7,450 compounds because it is more effective in killing B. burgdorferi and causes fewer side effects.

 Lyme disease affects more than 300,000 people annually, according to the Centers for Disease Control and Prevention. It can affect various organs, including the brain, skin, heart, joints and nervous system, and cause heart problems and arthritis if untreated.

Symptoms include fever, headaches, chills, and muscle and joint pain. 

Traditional antibiotics, such as doxycycline, are effective as an early course of treatment for the infection in the majority of patients, but it remains unclear why these drugs fail to treat 10% to 20% of patients, Rajadas said.

“Some researchers think this may be due to drug-tolerant bacteria living in the body and continuing to cause disease,” said Rajadas, who is also a member of the Lyme Disease Working Group at Stanford.

 “Others believe it’s an immune disorder caused by bacteria during the first exposure, which causes a perpetual inflammation condition. Whatever the cause, the pain for patients is still very real.

Azlocillin comes out on top

The drug, which is not on the market, was tested in mouse models of Lyme disease at seven-day, 14-day and 21-day intervals and found to eliminate the infection. For the first time, azlocillinwas also shown to be effective in killing drug-tolerant forms of B. burgdorferi in lab dishes, indicating that it may work as a therapy for lingering symptoms of Lyme disease.

Pothineni and Rajadas have patented the compound for the treatment of Lyme disease and are working with a company to develop an oral form of the drug. Researchers plan to conduct a clinical trial. 

Rajadas is also a professor of bioengineering and therapeutic sciences at the University of California-San Francisco. 

Other Stanford co-authors are Hari-Hara S. K. Potula, PhD, senior research scientist; postdoctoral scholars Aditya Ambati, PhD, and Venkata Mallajosyula, PhD; senior research scientist Mohammed Inayathullah, PhD; and intern Mohamed Sohail Ahmed. 

A researcher at Loyola College in India also contributed to the work.

The study was funded by the Bay Area Lyme Foundation and Laurel STEM Fund. 

Stanford Medicine integrates research, medical education and health care at its three institutions – Stanford University School of Medicine, Stanford Health Care (formerly Stanford Hospital & Clinics), and Lucile Packard Children's Hospital Stanford. For more information, please visit the Office of Communication & Public Affairs site at

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Lyme disease: Symptoms, transmission, and treatment

All about Borrelia, Lyme Disease & Treatment

  • Symptoms
  • Transmission
  • Diagnosis
  • Treatment
  • Prevention

Lyme disease, or borreliosis, is a potentially life-threatening condition that is transmitted to humans by blacklegged ticks.

The tick infects the person with the bacterium Borrelia burgdorferi (B. burgdorferi).

At first, a rash may appear. This can disappear without treatment, but in time, the person may develop problems with the joints, the heart, and the nervous system.

Lyme disease is the most common tick-borne infectious disease in the United States (U.S.). The ticks pick up the bacteria when they bite mice or deer that are carrying it.

It was first reported in 1977 in a town called Old Lyme, CT.

The Centers for Disease Control and Prevention (CDC) registered 25,435 confirmed cases of Lyme disease and 9,616 probable cases in 2015, an incidence of 8.9 cases in every 100,000 people.

The highest number was in Pennsylvania, with 7,351 confirmed cases. New England, the mid-Atlantic States, and the upper Midwest are most prone to ticks that can spread Lyme disease.

Here are some key points about Lyme disease. More detail is in the main article.

  • Lyme disease is the most common tick-borne disease in the U.S.
  • The disease can only be passed on through the bites of certain kinds of tick.
  • A common symptom of Lyme disease is an erythema migrans rash.
  • Without effective treatment, symptoms disappear, but more severe symptoms can emerge weeks, months, or years later.

Share on PinterestAn erythema migrans (EM) rash should be reported to a doctor, as it may indicate Lyme disease.

Initial signs and symptoms of Lyme disease are usually very mild.

Some people may not notice any symptoms, or they may think they have flu.

After the initial phase, further symptoms develop.

Symptoms can disappear, but the disease can affect the body in other ways, years later.

Stage 1: Early Lyme disease

Erythema migrans (EM) is a rash that often appears in the early stage of Lyme disease, from 3 to 30 days after infection, or 7 days on average.

EM affects 70 to 80 percent of people who are infected.

The rash:

  • typically begins as a small red area that expands over several days, to reach a diameter of 12 inches or 30 centimeters
  • may lose its color in the center, giving a bull’s-eye appearance
  • usually starts at the site of the tick bite but can appear elsewhere as the bacteria spread
  • is not painful or itchy but may feel warm to the touch

The rash may be less evident on darker skin.

Stage 2: Early disseminated Lyme disease

The rash will disappear after about 4 weeks, even without treatment, but other symptoms can emerge days to months after being bitten.

These include:

  • meningitis, or inflammation of the brain and spinal cord, leading to headaches and a stiff neck
  • additional rashes
  • fever and chills
  • swollen lymph nodes
  • fatigue
  • pain in tendons, muscles, joints, and bones, especially in the large joints
  • heart palpitations or irregular heart beat
  • facial palsy, or loss of muscle tone in one or both sides of the face
  • dizziness and shortness of breath
  • nerve pain and shooting pains, numbness or tingling in the hands or feet

These symptoms may go away without treatment within a few weeks or months, but, in time, the person may experience further complications.

Anyone who may have Lyme disease should get medical help immediately. Early treatment is more effective.

Stage 3: Late disseminated Lyme disease

Also known as late Lyme disease, this may be the first sign of illness in some people.

Symptoms can emerge weeks, months, and even years after initial infection if a patient has not received treatment, or if antibiotic treatment has not been fully effective.

In some patients, this may be the first sign of illness.

It can involve problems with the nervous system and the heart.

The person may have:

  • difficulty concentrating
  • sleep and vision problems
  • memory loss
  • numbness, pain and tingling
  • irregular heart beat
  • joint pain
  • paralysis of the face muscles

Around 60 percent of untreated patients will experience recurrent bouts of arthritis with severe joint swelling, especially in the large joints.

Post-treatment Lyme Disease Syndrome

Even after treatment, a few people may experience post-treatment Lyme disease syndrome, sometimes referred to as chronic Lyme disease.

This involves nonspecific symptoms, such as fatigue and joint pain, that can persist for months after treatment.

Antibiotics are unly to help, so treatment aims to relieve symptoms, for example through rest and anti-inflammatory medications.

The symptoms should resolve in time.

Share on Pinterest Lyme disease can only be transmitted by ticks.

In the U.S, B. burgdorferi, the Lyme disease-causing bacterium, enters humans through the bite of an infected blacklegged tick, either Ixodes scapularis or Ixodes pacificus.

The adult tick or the young nymph bores a tiny hole in the skin and inserts its mouthparts into the opening, attaching itself to the host.

Ticks tend to attach to hard-to-see areas of the human body, such as the scalp, armpits, and groin.

Generally, the tick must remain attached for at least 36 to 48 hours before transmitting the bacterium into a human.

As a result, the risk of getting Lyme disease from a tick, even where ticks are prevalent, is between 1.2 and 1.4 percent.

Most people get rid of the larger adults before they have time to transmit the bacterium, so human infections tend to occur as a result of bites from barely visible nymphs.

Is person-to-person transmission possible?

Lyme disease spread cannot spread between humans, for example by touching, kissing, or sexual contact.

Dogs and cats can get Lyme disease, but they cannot infect humans. There have been no documented cases of anyone contracting Lyme disease by eating venison.

Lyme disease cannot be passed on through the air, food, or water.

Lice, mosquitoes, fleas, or flies do not transmit it.

Pregnancy and breast-feeding

Some small studies have linked Lyme disease in pregnancy to birth defects or fetal death, but there has not been enough research to conclude that Lyme disease negatively affects pregnancy.

There are no reports of transmission through breast-feeding.

A woman who needs treatment for Lyme disease during pregnancy will receive a different kind of antibiotic treatment than usual.

Ideally, treatment should occur as soon as the EM rash appears.

If a person has been in an area where Lyme disease is common, and they have symptoms, treatment can start even without a blood test.

This is because the antibodies to the bacteria take from 2 to 6 weeks to show up in blood tests, so a blood test done within a month of infection may give a false result.

People should tell their doctor at once if they:

  • live in a high-risk area
  • have symptoms that could indicate Lyme disease
  • have recently been exposed to ticks

If early-stage Lyme disease is not treated, there is a serious risk of more severe symptoms later on, even years later.

Patients with swollen joints or neurological symptoms may be advised to have a PCR (polymerase chain reaction) test to check for bacterial DNA. Fluid is drawn from either the infected joint or the spine, in a spinal tap.

During the early stages of Lyme disease, treatment with antibiotic medication generally results in a rapid and complete recovery.

In the later stages, especially if the person has arthritis and neurological conditions, intravenous antibiotics, or antibiotic injections, will be necessary.

Even after treatment is over, patients may still test positive for anti-B. burgdorferi antibodies, but this does not necessarily mean they still have Lyme disease.

Share on PinterestAs the tick feeds, it can become engorged. Knowing the right way to remove a tick can help prevent further problems.

The incidence of Lyme disease appears to be on the rise in the U.S.

The National Science Foundation suggest this could be due to forest fragmentation, as smaller fragments of forest seem to harbor more ticks.

Small patches of woodland are common in cities and suburban and rural areas. They are a popular habitat for white-footed mice, because there are fewer predators.

White-footed mice are the main carriers of the bacteria that causes Lyme disease. When blacklegged ticks feed on the mice, they can pass on the bacteria.

The best way to prevent Lyme disease is to avoid tick bites.

Some ways to do this are:

  • be alert for symptoms
  • be aware of the risk, especially if living in or visiting New England, the upper Midwest or the mid-Atlantic states
  • use repellant on the skin, clothing, and hiking or camping gear
  • treat pets with anti-tick treatment
  • check your body, gear, clothes, and pets for ticks after spending time outdoors
  • shower after coming in from outside
  • dry clothes at a high temperature to kill ticks
  • ask pest control for advice about protecting your yard
  • discourage deer by fencing your yard
  • remove ticks quickly and correctly, and take a photo in case you need to show a doctor

When checking the body, the CDC suggest looking for ticks in the following places:

  • under the arms and behind the knees
  • in and around the ears
  • in the belly button
  • in head and body hair
  • between the legs
  • around the waist

If a tick is attached to the skin for less than 24 hours, it is unly to transmit Lyme disease.

  • Public Health
  • Infectious Diseases / Bacteria / Viruses