Most individuals who develop post-treatment Lyme disease syndrome, or PTLDS, also known as chronic Lyme disease, eventually recover, according to the Centers for Disease Control and Prevention. Some individuals may continue to experience symptoms for as long as six months from the onset of the bacterial infection.
While the exact cause of post-treatment Lyme disease syndrome is not known as of 2015, up to 20 percent of patients who take a two-to-four week course of antibiotics to treat the initial infection continue to experience joint and muscle aches as well as pain and extreme fatigue for six months or more, reports the CDC. It is believed that the damage to the tissues and immune system caused by the infection is responsible for the ongoing symptoms. Long-term antibiotic use is not helpful in treating PTLDS; severe side effects are known to occur.
The Lyme disease bacterium spreads through the bite of two different ticks, dependent upon the geographical region in which they are found, explains the CDC. Usually young tick, called a nymph, lodges in a low-visibility part of the body, such as the scalp or groin, and transmits the bacterium after remaining there for approximately two days. Because nymphs are difficult to identify visually, they can remain attached to the skin undetected, allowing sufficient time for them to pass the bacterium to the human host.