Recognizing Untreated Lyme Disease and Getting Treatment

Identify the Signs to Get Help Early

Lyme disease is a bacterial infection spread by black-legged ticks, commonly known as deer ticks. It is the most frequently seen vector-borne disease in the United States.

Symptoms of Lyme disease vary based on the severity of the case. The most notorious symptom, “bullseye rash,” doesn’t occur in everyone and can go unnoticed. Other symptoms may resemble those of other illnesses. This is why it is possible to be unaware that you have Lyme disease.

Lyme disease that goes untreated for many months or years may be harder to treat with antibiotics. Untreated cases can progress to serious, even fatal health conditions, from arthritis and nerve pain to cardiac arrhythmia (irregular heartbeat) or Lyme neuroborreliosis (inflammation of the brain and spine).

Potential Early Symptoms of Lyme Disease - Illustration by Jessica Olah

Verywell / Jessica Olah

It’s important to understand more about Lyme disease, what can happen if it goes unmanaged, and what can be done to treat it. The more vigilant you are, the better off you’ll be.

What Causes Lyme Disease?

Lyme disease is carried by the blacklegged tick, also known as the deer tick. This tick is found in the northeastern and upper midwestern United States. On the Pacific coast, Lyme disease is spread by the western blacklegged tick (also called the deer tick). 

When an infected tick bites you, a bacteria called Borrelia burgdorferi passes from the tick into your bloodstream. In order for this to happen, the tick must be attached to you for 36 to 48 hours. Most people are infected when they're bitten by immature ticks, which can be difficult to see. 

Symptoms of Lyme Disease

Lyme disease causes a range of symptoms that change and intensify as the Borrelia burgdorferi bacteria spreads to the rest of the body. Untreated cases can cause serious problems or lead to a fatal condition. What’s tricky, too, is that the onset of initial symptoms occurs anywhere from three to 30 days after exposure.

Clinically, there are three stages of Lyme disease: early localized disease, early disseminated disease, and late disseminated disease.

Early Localized Lyme Disease

Early localized disease, the initial manifestation, begins between three and 30 days after a bite. It is characterized by:

  • Bullseye rash and swelling, the most notorious symptom, occurs in 70% to 80% of cases. Clinically referred to as “erythema migrans,” its appearance varies—it can be a different color or shape—especially in people of color. It arises about a week after exposure to the bacteria.
  • Other symptoms of the first stage include fever, fatigue, headache, and joint pain. Very often, those with the condition—especially if there is no rash—feel as if they’re experiencing the flu.

Early Disseminated Lyme Disease

Disseminated Lyme disease symptoms arise as the bacterial infection works its way to other bodily systems, organs, and structures. Typically a month or more after exposure, symptoms have changed and may include:

  • Neck stiffness and headache
  • Rashes on parts of the body other than the original
  • Pain and severe swelling in the joints
  • Facial palsy, a drooping and/or paralysis of parts of the face
  • Inflammation and swelling of the brain and spine (aseptic meningitis)
  • Heart arrhythmia, palpitations, or inflammation
  • Pain, tingling, and numbness in hands and feet (radiculopathy)
  • Periods of dizziness and shortness of breath
  • Vision problems (conjunctivitis), in rare cases

Late Disseminated Lyme Disease

In its late disseminated phase, the bacterial infection has begun affecting nerve and joint structures, causing significant complications. This stage can begin weeks, months, or years after the tick bite.

Complications of Untreated Lyme Disease

If unchecked, the Lyme disease infection can spread to other bodily systems, causing significant damage. Untreated, complications of this condition can be very severe:

  • Arthritis: Prolonged infection with Lyme disease leads to chronic joint inflammation and swelling, usually in the knees (though other joints can be affected). These symptoms tend to arise within two years of infection, with periods of flare-ups and remissions. This arthritis is relatively difficult to manage, though antibiotics and steroids may be attempted.
  • Lyme carditis: If the bacteria reach the heart tissues, they can cause inflammation and lead to “heart block.” The electrical signals being sent between the upper and lower chambers of the heart are interrupted, impairing the coordination of the heartbeat. Though disruptive, this is rarely fatal.
  • Lyme neuroborreliosis: Inflammation of multiple nerves, including those in the spine and brain, is the chief characteristic of this condition. This can also affect the meninges—the layer of tissue surrounding the brain and spine—leading to meningitis, among other conditions. Antibiotic therapy, if applied promptly, tends to be effective as a treatment.

Even in cases where Lyme disease has progressed, antibiotic regimens—especially drugs like doxycycline—are generally successful in resolving problems.

Some see relapses of their condition despite treatment, something that’s commonly termed “chronic Lyme disease.” Clinically referred to as post-treatment Lyme disease syndrome (PTLDS), this is the persistence of fatigue, nerve and skeletal pain, and cognitive difficulties more than six months after treatment has ended.

There’s some debate about why PTLDS occurs in some but not others. Some believe it’s an autoimmune response triggered by the original infection. In addition, there is no consensus on treatment for this condition. Studies have shown that antibiotic treatments don’t help those with this condition.   

When to See a Healthcare Provider

Since Lyme disease can take different forms, and since it’s often confused with other conditions, it’s important to be proactive if you suspect the condition. What signs prompt medical help? Call the healthcare provider if:

  • You have a bullseye rash—or any kind of rash—following a tick bite.
  • You experience flu-like symptoms after a tick bite.
  • You experience symptoms of more advanced Lyme disease: arthritis, heart palpitations, facial paralysis, dizziness, and others.  

Lyme Disease Diagnosis

When it comes to cases of suspected Lyme disease, several factors help healthcare providers determine a diagnosis. Here’s a quick breakdown of what’s taken into account:

  • The presence of a tick: For the black-legged tick to successfully infect someone, it needs to be attached to a person for 24 to 36 hours. If you see a tick attached to your body, gently remove it and try to save it to bring to your healthcare provider for identification. Get medical help immediately.
  • The tick bite: While the bullseye bruise doesn’t always accompany the tick bite, the presence of the characteristic rash will certainly raise flags for healthcare providers.
  • Geographical location: Infection is expected only in areas where the black-legged tick is native. Infected ticks can be found in the Northeast, mid-Atlantic, Upper Midwest, and West Coast of the United States. They may also be found in Canada as well as parts of Europe and Asia.
  • Risky environments: Lyme disease will more often be suspected if you’ve had contact with environments conducive to black-legged ticks—areas of tall grass or forested regions. Gardeners and agricultural workers may be at particular risk.
  • Signs and symptoms: The presence of symptoms must be considered. Notably, these can resemble those of other diseases, so this assessment in itself is rarely conclusive.
  • Differential diagnosis: Since Lyme disease symptoms can resemble those of the flu or another type of infection, healthcare providers will also need to make sure other diseases aren’t causing symptoms.
  • Blood tests: When suspected, healthcare providers will use blood samples to test for the presence of antibodies to Lyme disease, with the ELISA for Lyme disease test being the most popular. Notably, blood samples are sometimes taken before antibodies have a chance to form, giving a negative result.

In those cases of untreated Lyme disease that have become more advanced and serious, as in its late disseminated phase, additional testing may be needed:

  • Electrocardiogram (ECG): This standard test of heart function measures its electrical activity.  
  • Echocardiogram: Another noninvasive test, this allows healthcare providers to visualize any effects on the heart, using ultrasound waves for imaging.
  • Magnetic resonance imaging (MRI): If infection may have spread to the brain or spine, MRI allows healthcare providers to work from two- or three-dimensional representations of affected areas.
  • Spinal tap: Assessment of the cerebrospinal fluid surrounding your brain and spine—harvested directly using a large surgical needle—may be necessary in cases of neurological inflammation due to Lyme disease.

How Common is Untreated Lyme Disease?

It’s difficult to get exact numbers when it comes to Lyme disease, in part because there’s only limited accounting of the condition’s frequency overall, and it’s often misdiagnosed or mistaken for other conditions.

Currently, it’s estimated that 476,000 people develop it in the United States every year, with 81% of the cases clustered in the Northeast, upper Midwest, and mid-Atlantic regions.

A significant—but shrinking—proportion of those with the disease end up progressing without treatment. Current estimates are hard to come by. In 2012, researchers estimated that about 16% of Lyme disease cases present without rash—increasing the chance that the case is missed, overall. From 1.6% to 7% of all infections have no symptoms.

Knowledge and awareness of this disease have grown over the past couple of decades, greatly improving outcomes. This improving prognosis is associated with better care and detection, leading to timelier intervention.

If you live in a hot spot area for black-legged ticks, never hesitate to reach out to your healthcare professional if you’re feeling sick or have a rash.

A Word From Verywell

While it’s always good to be careful about Lyme disease—especially if you live in an area where black-legged ticks are native—there’s also some perspective necessary. With effective medical intervention, this condition is easily and swiftly managed. Improvements in detection have also caused drastic reductions in associated complications.

With increased awareness of Lyme disease on the part of the broader population, it’s only natural that reports of this condition rise. This doesn’t, however, mean that you’re at greater risk or that you should avoid the woods; it simply means that people—and healthcare providers—are doing their respective parts.

Ultimately, Lyme disease doesn’t affect all that many people, and even less likely are cases where it gets severe. Nonetheless, don’t hesitate to get help if you suspect you have this condition. Good communication increases the chances of early detection, leading to timelier and more effective treatment.

Frequently Asked Questions

  • Can you have Lyme disease and not know it?

    Yes, symptoms of Lyme disease can often go unnoticed. An estimated one in six people with Lyme disease do not experience the tell-tale rash and up to 7% of people with Lyme disease have no symptoms. 

  • What happens if Lyme disease is untreated?

    Left untreated, Lyme disease can spread to joints and organs, causing significant damage. Arthritis, heart disease, and nervous system problems are common complications of untreated Lyme disease.  

  • How is Lyme disease diagnosed?

    In the initial stages, Lyme disease is diagnosed based on the appearance of a bulls-eye rash after a black-legged tick bite. Other symptoms that may accompany the first stage of Lyme disease include fever, fatigue, headache, and joint pain. It is often described as feeling like the flu.

    Blood tests are used to confirm a Lyme disease diagnosis. However, the test checks for Lyme disease antibodies, which often are not present in the early stages of infection. Blood tests are used to diagnose later stages of Lyme disease. 

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Mark Gurarie
Mark Gurarie is a freelance writer, editor, and adjunct lecturer of writing composition at George Washington University.