• Size: Tiny in size; adults measure one-eighth of an inch, while young nymphs may be the size of a pinhead.
  • Color: Dark brown to black body with darker legs.
  • Behavior: Like all ticks, the blacklegged tick is a bloodsucking ectoparasite. Ticks require a blood meal at each stage of life in order to grow. The adult female will engorge herself with blood to obtain the nourishment necessary to produce the thousands of eggs she will lay soon. Commonly known as the deer tick, blacklegged ticks have a two-year cycle beginning in the spring when the female tick deposits her eggs. Despite the thousands of eggs produced, only a small percentage will survive to maturity. They are usually found in wooded areas and fields where mammalian hosts such as deer, rodents and others live.

Blacklegged ticks are the primary vector of Lyme disease in the eastern United States. They also carry other diseases including Anaplasmosis, Babesiosis and Ehrlichiosis. The tiny larvae get their first blood meal from small rodents. The later-stage larvae attack deer and larger animals.

Ticks imbed their mouthparts, not their entire head, as some commonly believe, into their host. They inject an anti-clogging agent to keep the blood from clotting so they can feed. During feeding, blacklegged ticks may inject the bacterium that causes Lyme disease or other pathogens. Due to the small size of this tick, its presence can go unnoticed for several days. If the tick is attached in an inconspicuous area of the body, such as on the back or under the hairline, the potential for transmission of disease is increased if the tick itself is infected.

Lyme disease was first detected in 1976 in Lyme, Connecticut, when an unusually large number of children suffering similar symptoms came down with an unidentified illness. The illness was later found to be transmitted by the blacklegged tick, Ixodes scapularis. In 1981, a spirochete named Borrelia burgdorferi was isolated and confirmed as the causative pathogen.

Studies have shown that 90 percent of the blacklegged ticks may be infected with B. burgdorferi in parts of the northeastern states. Lyme disease most often begins with the appearance of a spreading bull’s-eye rash at the site of the bite. This rash, called erthema chronicum migrans or ECM, is seen in about 60 percent of patients. Most victims of Lyme disease report a flu-like illness at first and often dismiss the symptoms as a “24-hour bug,” overexertion or lack of rest. Lyme disease is very difficult to diagnose because each victim’s symptoms may differ.

For more information regarding tick-borne diseases, visit the website of the Centers for Disease Control.



Blacklegged ticks are primarily found in the eastern United States and are particularly common in the Northeast. They frequent wooded areas and fields and are more common around homes and buildings in secluded or rural areas. Unlike the brown dog tick, this species is rarely found indoors unless discovered on dogs or cats.


Tips for Control

Blacklegged ticks are difficult to control, therefore, the services of an experienced professional are recommended. Treatments may be necessary in shaded areas of the yard where these ticks are usually found. The best way to avoid tick bites is to stay away from tick-infested areas. It may sometimes be necessary to work or walk in areas potentially inhabited by ticks. If so, the following recommendations will reduce the chance of tick bites:
  • Wear long-sleeved shirts and long pants. Light colors are best so ticks are easier to detect.
  • Secure the bottom of pants inside socks or tie close around the ankles.
  • Wear a hat.
  • Tuck long hair under a hat.
  • Use tick repellent applied to clothing, particularly the lower body and the arms.
  • Carefully inspect your body after exiting infested areas. Have another person inspect your backside and back of your head.
  • Carefully inspect children for whom you are responsible if they have been in areas potentially infested by ticks.
  • Wash clothing in warm water and detergent immediately.
  • Never throw potentially infested clothing in a hamper with other clothes or onto the floor.
  • Protect pets by preventing them from venturing into tick-infested areas or consult your veterinarian for tick treatment products. Remember, your dog can also contract Lyme disease or sometimes fatal diseases such as Ehrlichiosis from ticks.
  • Inspect pets carefully for ticks after walking them in wooded areas or fields.
  • To remove a tick embedded in your skin, do not grasp it by the abdomen and pull. You may squeeze its stomach fluids into your skin, increasing the chance for infection. Use fine-tipped tweezers to grasp the tick by the head next to the skin and slowly pull backward. Working slowly permits the tick to withdraw its mouthparts so they do not detach and remain in the skin, causing irritation. Once the tick has been removed, cleanse the area well with soap and water. You may want to disinfect the bite site with alcohol or apply an antibiotic cream.