Persistent Symptoms of Lyme Disease

Getty Images

Some people who are diagnosed with Lyme disease and treated—at any stage—continue to experience troublesome symptoms. Most often, these go away within six to 12 months but may last more than a year. Specific persistent symptoms and their severity can vary. Some people have mild lingering symptoms, whereas others have debilitating symptoms that make it hard to get through the day, let alone take part in enjoyable activities.

You may have heard various terms for persistent symptoms, such as post-treatment Lyme disease (PTLD), post-treatment Lyme disease syndrome (PTLDS), long Lyme, or chronic Lyme. PTLD is a research term used to define the 10% to 20% of people who continue to experience symptoms after completing antibiotic treatment for Lyme disease. Those people meet the following criteria:

• a prior documented episode of Lyme disease meeting CDC criteria in which all objective signs resolve

• fatigue, widespread musculoskeletal pain, and/or cognitive difficulties which begin within six months, last for at least six months, and are significant enough to impair daily function

• the absence of specific co-morbid or pre-existing conditions which should otherwise explain symptoms.

Some doctors use the terms PTLD or PTLDS. Some use one of the other terms to more broadly include other sufferers, such as those who are still undergoing treatment or those who do not meet the CDC diagnostic criteria but have been clinically diagnosed with Lyme (for more information on diagnostic criteria, see Diagnosis & Testing).

Regardless of terminology, persistent symptoms of Lyme disease are real and well documented. However, the cause (or causes) are poorly understood. Current theories include:

Immune system dysregulation: The body’s response to fighting infection runs amok and persists long after it is helpful. This may be due to lingering spirochete (Lyme disease bacteria) proteins, persistent inflammation, or other autoimmune issues.

Damage to nerve pathways: Lyme disease is well known to affect the nervous system. Nerve damage may contribute to continued Lyme-related symptoms.

Lingering infection: It is possible there may be active infection that is hard to detect. Limited case studies, and studies in animal models, have shown evidence of persistent spirochetes, but there is not yet definitive evidence of persistent Lyme disease infection in humans. More research is needed.

Lyme disease isn’t the only infection that can cause long-term, potentially life-altering symptoms. The most recent and well known infection that can have long-term effects is COVID-19. Both long COVID and another illness, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), have overlapping symptoms with Lyme disease.

ME/CFS. This complex illness is characterized by extreme fatigue that does not improve with rest. It can follow a number of common infections, for example mononucleosis or Epstein-Barr, although not all cases are tied to infections. Research shows that people with chronic fatigue syndrome have abnormalities in the brain, particularly in the part of the brain that regulates hormones and vital functions (the hypothalamus) and the pituitary gland. Testing also has shown abnormalities in the part of the nervous system that controls blood pressure, heart rate, body temperature, and other vital body functions—many people with ME/CFS have an unusually high heart rate and low blood pressure when they have been standing for a while.

Long COVID. Tens of thousands of people in the United States have lingering illness following COVID-19. Recent data suggest that 15% to 20% of people diagnosed with COVID-19 have symptoms more than two months after testing positive. Symptoms of long COVID include fatigue, body aches, shortness of breath, difficulty thinking or concentrating, inability to exercise, headache, difficulty sleeping, dizziness, and pins-and-needles feelings. The National Institutes of Health RECOVER Initiative (Researching Covid to Enhance Recovery) is a consortium to better understand the long-term effects of COVID-19 and understand risk factors, prevention, and treatment of this syndrome. The hope is that this research will also improve the understanding of similar illnesses including persistent symptoms related to Lyme disease.