What Is Tick Bite Fever?

Tick bite fever is a bacterial infection transmitted by the saliva of a tick carrying the disease. A rash and other symptoms typically appear about a week after a bite, which might be painless. An ulcer, called an eschar, with a black spot in the center sometimes shows up and might be confused with a spider bite. Symptoms typically go away in a couple of weeks, but might need antibiotic therapy.

There are hundreds of species of ticks, but only two carry tick bite fever. The lxodidae, a hard-shelled tick, and argasidae, a soft-bodied parasite, transmit disease to humans. Usually it is a female tick bite that spreads bacteria because males typically die after they mate. These insects do not jump, but use their legs to crawl onto an animal or person in grasses where they lie in wait.

Signs of tick bite fever include fever, swollen lymph nodes near the site of the bite, and headache. The severity of symptoms depends on the species of tick, the age of the person bitten, and his or her overall health status. People with compromised immune systems might become more ill because their bodies cannot fight the infection.

Doctors test for tick bite fever by analyzing antibodies in the blood because the actual infection might not show up for weeks after a tick bite. Some people develop a rash that begins on the legs and arms and spreads to the stomach, soles of the feet, and palms of the hands. In rare cases, people might be allergic to tick saliva, leading to trouble breathing, numbness, and swelling. These symptoms generally need medical treatment.

For most people, tick bites can be treated with topical creams to control itching. An antibiotic cream might also prevent infection at the bite site. Unless troublesome signs develop, the discomfort usually resolves in about two weeks.

Ticks belong to the spider family of insects and have existed for millions of years. Some die off without a blood meal from an animal or human, but a few can live more than a year without feeding. Tick diseases are named for areas where they are found, such as African tick bite fever and Rocky Mountain spotted fever. These parasites are also identified by their preferred hosts, like deer ticks and dog ticks.

Preventing a bite can reduce the chance of contracting tick bite fever when hiking or walking in regions where ticks live. Pant legs should be tucked into socks or tall boots so ticks cannot crawl onto the skin. Light-colored clothing makes ticks visible so they can be promptly removed. Some people use insect repellents while camping or hiking in tick-infested areas. If a tick is found on the body, it can be removed with tweezers while wearing gloves to prevent contamination.