Outlook

Most patients diagnosed and treated with appropriate antibiotics early in the disease do well and have mild or no complications. However, if the diagnosis and antibiotic treatment are delayed, serious complications can occur. The complications can be varied; they can include nerve damage that results in hearing loss and paralysis; kidney, heart, or lung failure; meningitis; blindness; brain damage; clotting problems; tissue gangrene; and even death. Older patients usually do not do as well as younger patients, and patients that develop the major symptoms very soon after a tick bite (about two to five days) have a worse prognosis than those patients who develop symptoms later. If diagnosis and treatment are delayed, the mortality (death) rate even with treatment can be about 3%-5% and reportedly as high as 9% in patients over the age of 70 according to one study.