Lyme Disease: Causes, Symptoms, Prevention & Research Perspectives

Risk Factors

Several environmental and behavioral factors can increase your risk of contracting Lyme disease. Spending time in wooded, grassy, or brush-filled environments, particularly in endemic areas, increases the chances of encountering infected ticks. Activities such as hiking, camping, gardening, or hunting can place individuals in close contact with tick habitats. 

The disease is most common in regions like the northeastern United States, the upper Midwest, southern Canada, and parts of Europe where infected ticks are widespread. Ticks are most active during the warmer months from spring through early autumn, but they can also be active any time temperatures are above freezing. Wearing exposed clothing, failing to use insect repellent, or neglecting to perform thorough tick checks after outdoor activities can also contribute to increased risk.

Complications

If Lyme disease is not diagnosed and treated early, complications may arise in multiple systems of the body. One of the most common long-term effects is chronic arthritis, particularly in large joints such as the knees. This joint pain may persist or recur over time, leading to swelling and restricted mobility. 

Neurological issues are another complication, ranging from peripheral neuropathy (nerve damage causing pain or numbness) to memory and cognitive issues collectively referred to as “brain fog”.

In some cases, heart involvement can occur, resulting in electrical conduction disturbances known as Lyme carditis. A subset of patients may go on to develop Post-Treatment Lyme Disease Syndrome (PTLDS), in which fatigue, muscle aches, or cognitive difficulties continue for months after antibiotic treatment has ended. 

Researchers are still exploring whether PTLDS is caused by residual bacterial fragments, immune dysregulation, or other underlying mechanisms. Some scientists are also investigating the potential of research-only peptides to understand inflammatory and immune processes that might play a role in these long-term outcomes, though such work is still experimental and not yet clinically validated.

When to See a Doctor

Prompt medical attention is crucial if you believe you may have been bitten by a tick or if you develop any symptoms consistent with Lyme disease especially after spending time in high-risk outdoor areas. 

Even if you don’t recall a tick bite, the onset of symptoms like rash, fever, fatigue, joint aches, or facial weakness should prompt a visit to a healthcare provider. Early diagnosis can prevent the disease from progressing to more severe stages. For those who have already been diagnosed and treated but continue to experience lingering symptoms, follow-up care is important.

Although PTLDS symptoms typically improve over time, patients should consult with their physicians if symptoms persist or worsen, particularly if neurological or cardiac signs are present.

Prevention

Preventing Lyme disease starts with reducing your exposure to ticks. When venturing into wooded or grassy areas, wear light-colored clothing to make ticks easier to spot and remove. Tuck long pants into socks and wear long-sleeved shirts to minimize exposed skin. 

Use Environmental Protection Agency (EPA)-approved tick repellents that contain DEET, picaridin, or permethrin, which can be applied to both skin and clothing. After outdoor activity, check your body carefully, especially underarms, behind the knees, around the waist, in the hairline, and other warm, hidden areas where ticks like to attach. 

Showering soon after coming indoors can also help remove unattached ticks. Wash and dry outdoor clothing on high heat to kill any ticks hiding in the fabric. Additionally, check pets for ticks if they’ve been outside, as they can carry ticks into your home.