(months-to-years post-tick bite)
Approximately 60% of patients who were infected with Borrelia (the agent that causes Lyme Disease), but were not treated with antibiotics, go on to develop arthritis, neurologic symptoms (brain or nerves), and skin manifestations.
Antibiotics are also used for late Lyme disease and are usually curative.
As mentioned, CLD is not the same as late Lyme as evidence of persistent infection is lacking. Although there are many anecdotal reports of symptom improvement with antibiotics, high quality randomized placebo-controlled trials have consistently shown a lack of benefit. In fact, there is strong evidence showing potential harm in the use of antibiotics for symptoms attributed to CLD.