Lyme disease was first identified and named by researchers at Yale more than a decade ago. Now, Yale investigators have shown that fear of Lyme disease may in some cases cause more problems than the disease itself. According to a study published in the Annals of Internal Medicine  in March, anxiety about possibly getting Lyme disease following a deer tick bite can result in over-treatment by doctors and is associated with a high incidence of depression and stress among patients. That worry is often unfounded and may result in harm, especially from overuse of antibiotics.

Lyme disease is caused by bacteria spread through extended feeding on human blood by the tiny deer tick. The tick must be embedded in the flesh for at least 24 hours to spread the bacteria into the host. In the vast majority of cases, an infected bite will cause a bull's eye rash. Lyme disease can cause flu-like symptoms, swelling of the knees and, in very unusual cases, arthritis, facial paralysis and neurological disorders. A single course of antibiotics usually eradicates the disease and even later-stage manifestations normally respond to antibiotic therapy.

According to the Yale study, however, many patients don't believe it, or believe they have the disease when they do not. Out of 209 patients evaluated for this infectious disorder, 60 percent turned out not to have Lyme disease at all. Yet they still made an average of seven visits to the doctor, had four blood tests and underwent 42 days of antibiotic treatment.

High levels of depression (42 percent) and stress (45 percent) were present in those who turned out not to have the disease and more than half reported adverse drug reactions after taking antibiotics. Assistant professor of medicine M. Carrington Reid, M.D., who co-authored the study with clinical professor of medicine Robert T. Schoen, M.D., says, “We're not helping these patients if we simply give them a label of Lyme disease.” The study points to the need for better information for patients and physicians about Lyme disease.