Ticks (cont.)

Medical Author:
Medical Editor:

How is a tick bite diagnosed?

No tests exist that either identify tick bites or the type of tick once the tick dislodges from the host's body. However, doctors can examine the entire body, looking for ticks still attached, rashes, or signs of a tick-caused disease. If a tick is identified, the physician can better choose what additional tests should be done because some ticks are likely to transmit certain pathogens. Again, the web citations below have photos of ticks that can help distinguish ticks from biting insects, such as fleas, mites, or bedbugs.

Identification of the tick genus and species may help the physician determine what further tests may be scheduled. For example, blood tests for diseases such as Lyme disease, Rocky Mountain spotted fever, Ehrlichiosis, and tularemia are generally not positive for weeks after the exposure, even though symptoms may be present. Knowledge of the type of tick that caused the bite can help narrow the physician's possible diagnoses and even allow the physician to proceed with early therapy before a positive diagnosis is made.

Exams and tests should be done if an individual exhibits symptoms after a tick bite. Most tick bites do not have symptoms. If symptoms develop after a tick bite, the determination of which tests need to be performed can be optimized in consultation with an infectious-disease specialist.

What are the symptoms and signs of diseases transmitted by ticks?

There is a wide range of symptoms that usually develop days to weeks after the tick bite. The symptoms that become manifest depend on the particular microbe (pathogen) that is transmitted. For example, erythema migrans (a rash that is occasionally resembles a "bull's eye") is often the first sign of Lyme disease transmitted by a tick bite. Other symptoms can include weakness, nausea, fever, vomiting, palpitations, rash, joint pain, swelling, numbness, and confusion. This is not an all-inclusive list, and other symptoms and signs can develop depending on the pathogen transmitted by the tick bite. More than one disease may be transmitted with tick bites; for example; some individuals may be infected with Lyme disease and babesiosis at the same time.

Picture of erythema migrans (EM or bull's eye rash)
Picture of erythema migrans, known as EM or bull's-eye rash
Medically Reviewed by a Doctor on 5/27/2014

Patient Comments

Viewers share their comments

Ticks - Bite Symptoms Question: What were your symptoms associated with a tick bite?
Ticks - Diagnosis Question: What types of tests or exams led to a diagnosis of a tick-related infection in you or someone you know?
Ticks - Removal Question: Do you know the correct way to remove a tick? Please share your experience.
Ticks - Treatment Question: What kinds of treatment did you use or receive to treat a tick bite or tick-caused infection?
Ticks - Prevention Question: If you live in a tick-prone region, how do you prevent bites?