There are many different types of ticks in the United States, some of which are capable of transmitting infections. The risk of developing these infections depends upon the geographic location, season of the year, type of tick, and, for Lyme disease, how long the tick was attached to the skin.
While many people are concerned after being bitten by a tick, the risk of acquiring a tick-borne infection is quite low, even if the tick has been attached, fed, and is actually carrying an infectious agent. Ticks transmit infection only after they have attached and then taken a blood meal from their new host. A tick that has not attached (and therefore has not yet become engorged from its blood meal) has not passed any infection. Since the deer tick that transmits Lyme disease must feed for >36 hours before transmission of the spirochete, the risk of acquiring Lyme disease from an observed tick bite, for
example, is only 1.2 to 1.4 percent, even in an area where the disease is common.
The organism that causes Lyme disease, Borreliaburgdorferi, lies dormant in the inner aspect of the tick’s mid-gut. The organism becomes active only after exposure to the warm blood meal entering the tick’s gut. Once active, the organism enters the tick’s salivary glands. As the tick feeds, it must get rid of excess water through the salivary glands. Thus, the tick will literally salivate organisms into the wound, thereby passing the infection to the host.
If a person is bitten by a deer tick (the type of tick that carries Lyme disease), a healthcare provider will likely advise one of two approaches:
- Observe and treat if signs or symptoms of infection develop
- Treat with a preventive antibiotic immediately
There is no benefit of blood testing for Lyme disease at the time of the tick bite; even people who become infected will not have a positive blood test until approximately two to six weeks after the infection develops (post-tick bite). The history of the tick bite will largely determine which of these options is chosen. Before seeking medical attention, the affected person or household member should carefully remove the tick and make note of its appearance. Only the Ixodes species of tick, also known as the deer tick, causes Lyme disease.
How to Remove a Tick
The proper way to remove a tick is to use a set of fine tweezers and grip the tick as close to the skin as is possible. Do not use a smoldering match or cigarette, nail polish, petroleum jelly (eg, Vaseline), liquid soap, or kerosene because they may irritate the tick and cause it to behave like a syringe, injecting bodily fluids into the wound.
The proper technique for tick removal includes the following:
- Use fine tweezers to grasp the tick as close to the skin surface as possible.
- Pull backwards gently but firmly, using an even, steady pressure. Do not jerk or twist.
- Do not squeeze, crush, or puncture the body of the tick, since its bodily fluids may contain infection-causing organisms.
- After removing the tick, wash the skin and hands thoroughly with soap and water.
- If any mouth parts of the tick remain in the skin, these should be left alone; they will be expelled on their own. Attempts to remove these parts may result in significant skin trauma.