Tick Bite Symptoms

Redness, itching, and swelling are commonly seen at the site of a tick bite.

• Lyme disease is now the most common tick-borne illness in the United States and throughout the world. It has been reported in all 48 continental states but is most common in the coastal mid Atlantic, the northern West Coast, Wisconsin, and Minnesota. The hallmark target lesion, a red circular rash with a pale center, occurs at the site of the bite within 2-20 days after the bite in 60-80% of cases. The rash may be accompanied by fatigue, headache, joint aches, and other flulike symptoms. Some 10% of untreated people develop neurologic symptoms (such as facial droop or tingling in the arms and legs), skeletal symptoms (large joint swelling), or cardiac problems (slowing of the electrical impulses of the heart). Years after the initial symptoms go away, untreated people can go on to have chronic problems including arthritis, inflammation of the heart muscle, or inflammation of nerves.


• Rocky Mountain spotted fever is most prevalent in the south central and coastal southern states. Fever and flulike symptoms usually begin 4-10 days after the tick bite. The hallmark of the disease is a rash that typically begins on the wrists and ankles and spreads centrally to the trunk, usually sparing the face. The rash is seen during the first 2 weeks of the illness.


• Relapsing fever is found worldwide and, in the United States, is most prevalent in rural western states. Following the tick bite, there is an incubation period of about 7 days, after which the person develops a high fever (usually greater than 102.2°F), headache, joint aches, and other flulike symptoms. The fever begins suddenly and lasts about 3 days, followed by a period of days to weeks with no fever. After this period, the fever and other symptoms often return. If treated appropriately, relapses occur less often and are less severe than if untreated.


• Colorado tick fever is most prevalent in the Rocky Mountain states, California, and Oregon. Symptoms begin suddenly 3-6 days following the tick bite and include fever, headache, and flulike symptoms. Symptoms usually last for 5-8 days and then go away by themselves. Three days later, up to 50% of people develop a generalized rash.


• Ehrlichiosis is most prevalent in the coastal mid Atlantic and southern Atlantic states, northern West Coast, Wisconsin, Minnesota, and south-central states. After a tick bite, the incubation period ranges from 1-21 days and is followed by fever, headache, and flulike symptoms. A minority of people with ehrlichiosis develop a generalized rash.


• Babesiosis is most prevalent in the coastal southern New England and mid Atlantic states. After a tick bite, the incubation period is 1-4 weeks and is followed by the gradual onset of loss of appetite and fatigue. A few days later, fever and flulike symptoms develop. A rash is not a feature of this disease. If a rash develops, Lyme disease should also be considered as a possible diagnosis.


• Tularemia is most prevalent in the south-central states, Montana, and South Dakota. After a tick bite, the incubation period is 3-5 days and is followed by sudden fever, headache, and flulike symptoms. At the bite site, the skin may break down, leaving an open sore with surrounding inflammation.


• Q fever is found worldwide and affects both wild and domestic animals. Tick-borne transmission to humans is rare. Fewer than 10 cases are reported each year in the United States. The most common symptom is a flulike illness with fever and headache.


• Tick paralysis has been reported worldwide, but most human cases occur in North America and Australia. It develops 5-6 days after an adult female tick attaches. Over the next 24-48 hours, muscle weakness progresses to paralysis. It primarily affects children. Because the tick secrets a neurotoxin (nerve poison), removing the tick causes rapid recovery.