How can Lyme disease last for years?
Category: Health Published: October 9, 2015
By: Christopher S. Baird, author of The Top 50 Science Questions with Surprising Answers and Associate Professor of Physics at West Texas A&M University
If treated, Lyme disease does not last for years. However, for some people, the after-effects of the disease can linger for months and sometimes even years. Alternative medicine providers call this condition "Chronic Lyme disease," but this title is simply wrong. For a person who has been infected with Lyme disease and then treated, the bacteria that causes Lyme disease is measurably no longer present in his body, even though he may still feel some symptoms. The correct title for this condition is therefore "Post-treatment Lyme Disease Syndrome."
Lyme disease is an infection caused by a bacteria known as Borrelia burgdorferi. This bacteria is delivered to humans through tick bites. From the bite site, the bacteria can enter the bloodstream and spread throughout the body. Usually, but not always, an infectious tick bite causes a characteristic red rash at the site of the bite. Other symptoms include fever, muscle soreness, headache, fatigue, and dizziness. In a few cases, symptoms can also include mood swings, memory loss, and sleep disturbance. If left untreated for too long, Lyme disease can lead to nerve damage, thereby causing shooting pain, numbness, and even paralysis.
The good news is that since Lyme disease is caused by bacteria, antibiotics do a good job of eliminating the disease. Taking antibiotics for one to four weeks, as directed by a doctor, successfully kills all the Lyme-disease bacteria in the patient's body. Unfortunately, a small percentage of people continue to feel symptoms for many months or even years after these bacteria have been eliminated. For such a person, calling his condition Chronic Lyme disease is incorrect since Lyme-disease bacteria are no longer present in his body. Also, since there are no Lyme-disease bacteria in his body, giving such a person more antibiotics over the course of months and years accomplishes nothing.
Researchers do not currently know conclusively what causes Post-treatment Lyme Disease Syndrome. There are two likely culprits: residual tissue damage and auto-immune malfunction. As mentioned earlier, the Lyme-disease bacteria can damage nerves. Depending on the amount of damage, it can simply take months for the nerves to heal, even long after the bacteria are gone. The good news is that they eventually do heal. Almost all people with Post-treatment Lyme Disease Syndrome eventually feel better. The other possible culprit is an auto-immune disorder that is triggered by the Lyme disease. The patient's own immune system works so hard at killing off the infectious bacteria that it ends up attacking the patient's own healthy cells long after the bacteria are gone. Again, most people that experience this effect eventually feel better after several months.
Unfortunately, many of the symptoms of Post-treatment Lyme Disease Syndrome; muscle soreness, joint pain, headache, fatigue, malaise, etc.; are vague symptoms that could be caused by many other conditions. Lupus, Crohn's disease, HIV, fibromyalgia, CFS, multiple sclerosis, and rheumatoid arthritis are all conditions that could be easily mistaken as Post-treatment Lyme Disease Syndrome. For this reason, the number of people misdiagnosed with Post-treatment Lyme Disease Syndrome or "Chronic Lyme disease" is likely high. Fortunately, a simple blood test for elevated levels of the corresponding antibody can determine whether a person has had Lyme disease, even if the Lyme-disease bacteria are no longer present. Since antibody levels can stay elevated long after the bacteria that triggered them are gone, a positive antibody blood test does not mean that a person currently has Lyme disease, just that he has had Lyme disease in the past.
Some alternative medicine providers use the phrase "Chronic Lyme disease" as a catch-all diagnosis for any person experiencing general fatigue. Such a diagnosis is neither logical nor helpful. If a patient did not receive a tick bite, did not develop a rash, does not have the other symptoms, and does not have positive blood tests, there is no scientific reason to assume that the patient has Lyme disease or has ever had Lyme disease. Misdiagnosing a patient prolongs the time before he is able to find and treat the real cause of his symptoms. Since the concept of Chronic Lyme disease as a diagnosis for general fatigue is not supported by scientific evidence, any website or publication that claims this should be approached with skepticism.
The CDC states,
It is not uncommon for patients treated for Lyme disease with a recommended 2 to 4 week course of antibiotics to have lingering symptoms of fatigue, pain, or joint and muscle aches at the time they finish treatment. In a small percentage of cases, these symptoms can last for more than 6 months. Although sometimes called "chronic Lyme disease," this condition is properly known as "Post-treatment Lyme Disease Syndrome" (PTLDS)...studies have not shown that patients who received prolonged courses of antibiotics do better in the long run than patients treated with placebo.