Bites: Tick

Ticks can carry and transmit a variety of organisms, such as bacteria, spirochetes, rickettsiae, protozoa, viruses, nematodes and toxins, sometimes transmitting several pathogens in one bite. Most tick bites, however, do not cause disease.

Of the three families of ticks, hard ticks (those with a hard plate that protects them) and soft ticks (which do not have a protective plate) cause illness. The Ixodes, which can transmit Lyme disease, is an example of a hard-plated tick. Hard-plated ticks usually must feed for many hours or days to transmit disease. In the United States, the only soft tick that can transmit disease is the Ornithodoros, which can infect a person with relapsing fever. Soft ticks usually feed for less than an hour and can transmit disease in less than a minute.  

In the United States, 82 species of ticks cause nine major diseases: Lyme disease, Rocky Mountain spotted fever, Colorado tick fever, tularemia, Southern tick-associated rash, Q fever, human ehrlichiosis, babesiosis and tick paralysis.

Causes

Ticks must have a blood meal from a host mammal, reptile or bird to progress in their development. The risk of being bitten and infected by a tick is greatest in May and June. They find a host by waiting for one to pass where they perch. People usually pick up ticks from woody underbrush, tall grass or weeds, and the fur of outdoor pets. Once on a host, the tick bites the skin, embeds its head and taps into a blood source -- a small vein or capillary. Some ticks secrete a material that glues them to the host. The Ixodes secretes a substance that prevents blood from clotting and interferes with the immune system in the area where they are attached.

Symptoms

Unless you see the tick while it is attached to you, you may not know you've had a tick bite, and you may have no reaction to it.

These are symptoms of a reaction to a tick bite, or to illness carried by a tick:

• Red ring or "bull's-eye" rash, called erythema chronicum migrans, which quickly expands, usually occurring three to 30 days after a bite. The rash can be a few inches to up to two feet in diameter and can last up to three weeks.

• Increased pain, redness, swelling and fever; this can indicate an infection from the bite.

• A general feeling of not being well about two weeks after a tick bite; this can signal a tick-borne illness.

The wood tick is the size of an apple seed with a white mark near its head. The deer tick is the size of a poppy seed with an orange-brown spot near the head

First Aid

• If you discover a tick on your skin or clothing, remove it immediately. The sooner you remove it, the less your chance of picking up infectious organisms.

• Don't try to remove the tick using nail polish, solvents, gasoline, petroleum or alcohol, or try burning the tick with a match. These methods can cause the tick to release harmful secretions under the skin.

• Use tweezers to grasp the tick as close to the skin as possible. Slowly and gently pull the tick up from the skin until it releases its grip. Avoid twisting or jerking to prevent breaking off the head or mouth. Do not crush the tick. If tweezers are not available, pull off the tick using a loop of thread around the jaws. Try not to squeeze the tick during removal. Squeezing may inject infectious material into the skin. Avoid touching the tick and its secretions, or use gloves.

• If the tick's head stays in the skin, use a sterile needle to remove it.

• Clean the skin thoroughly with soap and water after the tick has been removed.

• Keep the tick in a jar labeled with the date of the bite and its location. Keep the tick until you are sure there are no signs or symptoms of a tick-borne illness. Symptoms of tick-borne illnesses are a rash and symptoms similar to the flu: muscle aches, swollen lymph nodes, fever and joint pains.

Prevention

The best way to prevent ticks from attaching to your skin is to find them before they attach. Do regular "tick checks" when you are in the woods. Twice daily, inspect your skin, scalp, hair and clothing for ticks. Check these areas on your own and your child’s body:

• Under the arms

• In and around the ears

• Inside belly button

• Back of the knees

• In and around the scalp

• Between the legs

• Around the waist

Also check your pets for ticks. Avoid being a target for ticks. Keep long hair from accidentally contacting vegetation. Wear long pants, long-sleeved shirts, a hat, socks and shoes. Light-colored, tightly woven clothing will allow you to see ticks before they have a chance to bite you. Tuck your shirt into your pants and your pants into your socks to help prevent ticks from attaching themselves to your skin. Walk in the center of the trail.

When you anticipate exposure, apply insect repellent. Adults should apply insect repellent containing 20 to 30 percent DEET (N-diethyl-m-toluamide) to skin or clothing. DEET should not be used on children younger than 2 months. Insect repellents containing DEET with a concentration of 10 percent appear to be as safe as products with a concentration of 30 percent when used according to the directions on the product labels. Consult your child's health care provider if you have concerns or need advice on using insect repellents on your child. Parents should apply DEET to their children, avoiding the child’s hands, eyes and mouth. DEET will only last a few hours before you need to reapply. DEET at concentrations greater than 30 percent are not recommended, especially for young children and those with sensitive skin. 

Permethrin insecticide kills ticks. It can be applied to shoes and clothing, but not to skin. It provides protection for several days.

Remove ticks from your clothes before going indoors. To kill ticks that you may have missed, wash your clothes with hot water and dry them using high heat for at least one hour.

Perform daily tick checks after being outdoors, even in your own yard. Inspect all parts of your body carefully. Remove ticks immediately.

Create a tick-safe zone around homes, parks and recreational areas. Here's how:

• Remove leaf litter and clear tall grasses and brush around homes and at the edges of lawns.

• Place wood chips or gravel between lawns and wooded areas to restrict tick migration to recreational areas.

• Mow the lawn and clear brush and leaf litter frequently.

• Don’t attract deer, which can carry the ticks, to your yard.

• Consider a single application of a pesticide that kills ticks (called an acaricide) at the end of May or beginning of June. Check with local health officials about the best time to apply acaricide in your area, as well as any rules and regulations related to pesticide application on residential properties. Or, contact a professional pesticide company to apply pesticides at your home.