Lyme Disease – Symptoms and Causes

Overview

Lyme disease comes from borrelia bacteria, typically transmitted through tick bites. The ticks carrying this bacteria exist across the United States.

The highest infection rates occur in the upper Midwest, northeastern and mid-Atlantic regions. The disease is also prevalent in Europe and parts of Canada, particularly south central and southeastern regions.

People who spend time in tick-friendly environments face greater risk of infection. These environments include:

• Grassy areas
• Brushy terrain
• Wooded locations

Taking proper precautions when visiting these areas can significantly reduce your chance of contracting Lyme disease. Understanding where ticks live and how they spread the bacteria is an important step in prevention.

Symptoms

Lyme disease typically develops in stages, with different symptoms appearing at each phase. Not everyone goes through every stage or exhibits the same signs. Some people might not even notice the initial tick bite.

Early Signs

A circular rash often appears 3 to 30 days after being bitten by an infected tick. This rash typically expands slowly from the bite site, sometimes creating a bull’s-eye pattern with a clear center.

The affected skin usually feels warm but rarely itches or hurts.

Other common early symptoms include:

• Fever
• Headache
• Extreme fatigue
• Stiff joints
• Muscle pain
• Swollen lymph nodes

Not everyone develops the characteristic rash, which makes early detection challenging for some patients.

Progressive Symptoms

If left untreated, Lyme disease typically advances within 3 to 10 weeks of the tick bite. During this stage, the infection spreads throughout the body.

Symptoms may include:

• Multiple rashes appear on different body parts
• Neck stiffness
• Facial muscle weakness (on one or both sides)
• Heart rhythm problems
• Nerve pain radiating from back and hips to legs
• Numbness or weakness in hands and feet
• Eye inflammation and swelling
• Vision problems or eye pain

These symptoms indicate the infection is spreading beyond the initial bite location.

Advanced Complications

Without proper treatment, Lyme disease can progress to its most serious stage. Advanced symptoms may begin 2 to 12 months after infection.

In the United States, the most common advanced symptom is arthritis affecting large joints, particularly the knees. This can cause:

• Persistent joint pain
• Significant swelling
• Stiffness lasting weeks or months
• Symptoms that come and go

In Europe, a specific skin condition called acrodermatitis chronica atrophicans may develop. This causes discoloration and swelling on the backs of hands, tops of feet, elbows, or knees. Severe cases can damage tissues and joints.

These advanced complications may appear months or even years after the initial tick bite.

When Medical Care Is Needed

You should see a healthcare provider if you develop any Lyme disease symptoms, especially if you:

1. Recently visited an area where ticks are common
2. Found a tick attached to your skin
3. Live in a region where Lyme disease occurs

Important note: Most people with Lyme disease don’t recall being bitten by a tick. Many Lyme symptoms resemble other common illnesses, making diagnosis difficult.

If you know you’ve been bitten by a tick or spent time in tick habitats, monitor yourself for symptoms and seek medical care if they develop.

What Causes Lyme Disease

Lyme disease develops when specific bacteria enter the human bloodstream through tick bites. In North America, the black-legged tick (sometimes called the deer tick) is the main carrier of these harmful bacteria.

European cases come from a different but related bacterial species, carried by ticks sometimes known as castor bean ticks, sheep ticks, or deer ticks. Ticks become carriers of Lyme disease by feeding on infected animals like deer or rodents.

The bacteria don’t harm the ticks but can be passed to humans during feeding. When a tick attaches to human skin, it may feed for several days, swelling significantly as it fills with blood.

The risk of infection increases the longer an infected tick remains attached. Removing ticks within 24 hours greatly reduces the chance of getting Lyme disease. Both adult and young ticks (nymphs) can transmit the bacteria.

Important facts about tick bites:

• Young ticks are especially dangerous because they’re:
  • Extremely small (about the size of a poppy seed)
  • Difficult to spot on the skin
  • Often able to feed unnoticed

Many people who develop Lyme disease never recall seeing a tick on their body due to the tiny size of these parasites.

Risk Factors

Your chance of getting Lyme disease depends on your exposure to environments where ticks live. These risk factors include:

Geographic Location

• Highest risk in upper Midwest and northeastern United States
• Common in mid-Atlantic states
• Present in south central and southeastern Canada
• Found throughout Europe

Environmental Exposure

• Wooded areas
• Shrubby terrain
• Grassy fields

Seasonal Timing

• Higher risk during spring, summer, and fall months
• Ticks remain active whenever temperatures exceed freezing point

These factors can help you assess your personal risk level and take appropriate precautions when spending time outdoors.

Long-term Issues

Some people with Lyme disease experience symptoms that persist after treatment. These ongoing problems may include joint pain that first appeared with Lyme disease and hasn’t improved. Body aches, constant tiredness, and memory difficulties are also common complaints.

Medical experts sometimes call these lingering symptoms post-treatment Lyme disease syndrome (PTLDS). The exact causes remain unclear, but several possibilities exist:

• Treatment that didn’t fully clear the infection
• Getting infected with Lyme disease again
• The body’s immune response to remaining bacterial fragments
• Autoimmune reactions where the immune system attacks healthy tissues
• Other undiagnosed health conditions

Ways to Stay Safe from Ticks

Using Tick Repellents

Keep ticks away with the right products. Apply a 0.5% permethrin spray to your clothes, shoes, and camping equipment. Some outdoor gear comes already treated with this protection.

For your skin, use EPA-registered repellents containing one of these ingredients:

• DEET
• Picaridin
• IR3535
• Oil of lemon eucalyptus (OLE)
• Para-menthane-diol (PMD)
• 2-undecanone

Important safety note: Don’t use products with OLE or PMD on children younger than 3 years old. Avoid applying any repellent to your face.

Wearing Protective Clothing

Dress smartly to block ticks from reaching your skin:

1. Choose light-colored clothes that make ticks easy to spot
2. Skip open-toed footwear and sandals
3. Wear long sleeves and tuck shirts into pants
4. Pull pants over socks to create a barrier

These simple clothing choices create barriers that keep ticks from reaching your skin.

Checking Your Body

Look for ticks after being outdoors:

• Take a shower soon after coming inside to wash away loose ticks
• Use a mirror to inspect hard-to-see areas
• Pay special attention to:
  • Underarms
  • Hair and hairline
  • Ears
  • Waist
  • Between legs
  • Behind knees
  • Inside belly button

Don’t forget to treat your clothes. Before washing, put outdoor clothes in a hot dryer for at least 10 minutes to kill any ticks.

More Safety Tips

Keep yourself and your surroundings tick-free with these additional steps:

Inspect your pets for ticks every day if they roam outdoors. Ticks can hitch rides on animals and then transfer to humans.

When hiking or exploring, stay on clear paths whenever possible. Ticks often wait in tall grass and dense wooded areas. They can easily attach to people passing by.