Ehrlichiosis is an infectious disease that can be passed to humans by ticks. It causes fever, chills, headache (often severe), general ill feeling (malaise), nausea and vomiting, and a purple or red rash.

Symptoms usually start from 1 to 21 days (average of 7 days) after the tick bite. Ehrlichiosis is usually treated with prescription medicine.

The disease most frequently occurs in the southern and south-central United States, especially in Georgia, Missouri, and Oklahoma.