Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
The initial infection can occur with minimal or no symptoms. But many people experience a flulike primary illness or a characteristic rash several days to a few weeks following a tick bite.
The flulike illness usually occurs in the warm weather months when flu (influenza) does not occur.
The rash is a red rash that grows in size daily.
It is called erythema migrans.
The U.S. Centers for Disease Control and Prevention (CDC) defines this rash
as a skin lesion that typically begins as a red spot and expands over a period
of days to weeks to form a large round lesion, at least 5 cm (about 2 inches) across. A red circular spot which begins within hours and is smaller is usually a reaction to the tick bite.
When the rash occurs at the site of the tick bite, it is called a primary lesion. Multiple secondary lesions can occur that are a reaction to the infection and are not due to multiple tick bites. All of these lesions can grow up to the to the size of a football. This growing in size is characteristic of Lyme disease.
Its shape can be circular or oval.
As it grows, the rash can remain red throughout, although it often can develop a clear area. In a minority, it may take on the appearance of a target with multiple rings (alternating red with clear skin). This is known as a bull's eye lesion.
Left untreated, symptoms of the primary illness usually will go away on their own within a few weeks although the rash may recur.
Later, additional symptoms may occur. The organs affected later may lead to
the following conditions:
Facial palsy is paralysis of the facial nerve that causes the facial muscles to be uneven (This may get better without treatment.)
Intermittent episodes of arthritis last about a week and usually involve the knee or wrist. These may recur over periods of weeks to months, and if the Lyme disease remains untreated, about 10% of people who have these episodes develop persistent arthritis in the knee. Occasionally, people with Lyme disease can present with an acute arthritis in the knee without a clear history of a rash or other joint
Inflammation of the heart (carditis)
results in irregularities in heart rhythm