The lone star tick does not transmit Lyme disease.

Patients bitten by lone star ticks will occasionally develop a circular rash similar to the rash of early Lyme disease. The cause of this rash has not been determined; however, studies have shown that it is not caused by Borrelia burgdorferi, the Lyme disease bacterium.

The rash may be accompanied by fatigue, headache, fever, and muscle and joint pains. This condition has been named southern tick-associated rash illness (STARI). In the cases of STARI studied to date, the rash and accompanying symptoms have resolved following treatment with oral antibiotics. STARI has not been linked to any arthritic, neurological, or chronic symptoms. [2]

The lone star tick, Amblyomma americanum, is found throughout the southeastern and south-central states. The distribution, range and abundance of the lone star tick have increased over the past 20-30 years, and lone star ticks have been recorded in large numbers as far north as Maine and as far west as central Texas and Oklahoma. All three life stages (larva, nymph, adult) of the lone star tick will feed on humans, and may be quite aggressive. Lone star ticks will also feed readily on other animals, including dogs and cats, and may be brought into the home on pets. The saliva from lone star ticks can be irritating; redness and discomfort at a bite site does not necessarily indicate an infection.

The rash of STARI is a red, expanding bulls eye lesion that develops around the site of a lone star tick bite. The rash usually appears within 7 days of tick bite and expands to a diameter of 8 centimeters (3 inches) or more. The rash should not be confused with much smaller areas of redness and discomfort that can occur commonly at tick bite sites. Unlike Lyme disease, STARI has not been linked to any arthritic, neurological, or chronic symptoms.

The cause of STARI is unknown. Studies have shown that is not caused by Borrelia burgdorferi, the bacterium that causes Lyme disease. Another spirochete, Borrelia lonestari, was detected in the skin of one patient and the lone star tick that bit him. However, subsequent study of over two dozen STARI patients has found no evidence of B. lonestari infection. In the cases of STARI studied to date, the rash and accompanying symptoms have resolved promptly following treatment with oral antibiotics.

In general, tick-borne illness may be prevented by avoiding tick habitat (dense woods and brushy areas), using insect repellents containing DEET or permethrin, wearing long pants and socks, and performing tick checks and promptly removing ticks after outdoor activity. Persons should monitor their health closely after any tick bite, and should consult a physician if they experience a rash, fever, headache, joint or muscle pains, or swollen lymph nodes within 30 days of a tick bite.  [1]