Lyme Disease Transmissable To Humans
 
General Information
  • Lyme Disease is classified as a vector-borne, zoonotic illness – it is spread by ticks (the vector, or agent of transmission). The organism which causes Lyme disease is a spiral-shaped bacterium called Borrelia burgdorfei and it has been found in two species of ticks collected from many areas of BC including Vancouver Island, the Lower Mainland, the Sunshine Coast, the Fraser Valley and the Kootenays.
  • The tick that spreads Lyme Disease in BC is the blood-feeding western black-legged tick (Ixodes pacificus), which are about the size of a sesame seed.
  • While most tick bites do not result in disease, some do.
  • In BC, less than 1 percent of ticks tested carry the bacteria that causes Lyme Disease, and there is only a very small chance of the bacteria being transmitted to a human that has been bitten. However, the disease can be serious, so it is worth taking steps to avoid being bitten.
  • Ticks prefer habitat that includes wooded regions and areas with tall grass; this habitat preference also coincides with the preferred habitat of their primary host, black-tailed deer (Odocoileus hemionus).
  • Ticks attach to people or animals as they pass by, burrow part way into the skin, bite, draw blood, then drop off.
  • Ticks are easiest to spot when they are feeding on a host. During the blood meal, only the mouth parts of ticks are inserted beneath the skin of the host, while the posterior body remains exterior to the host’s body. Once fully engorged with blood, ticks detach and move onto vegetation.
  • As of 2013, there have been over 60 confirmed cases of Lyme Disease in British Columbia.
Images
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Western Black-legged Tick
Western black-legged ticks (Ixodes pacificus) is responsible for the spread of Lyme Disease along the Pacific coast, mostly in southern British Columbia. (Source: Public Health Image Library (PHIL). James Gathany; William Nicholshon. Available online: http://phil.cdc.gov.)
Symptoms and Treatment
Symptoms:
  • If you have the following symptoms within days or weeks after being bitten by a tick, consult your family physician or other healthcare professional. Tell your doctor when and where you were bitten by a tick.
  • Symptoms include a skin rash that looks like a "bull's eye" and may be quite large (5 cm or 2 inches) in diameter may develop. It often spreads out from where the tick bite was.
  • Also, general symptoms of:
    • fever;
    • headache;
    • muscle and joint pains;
    • fatigue or weakness of the muscles of the face;
  • In some cases paralysis may occur. The paralysis usually starts in the feet and legs and gradually works its way up to the upper body, arms and head. This paralysis can develop from within a few hours to several days.
Treatment:
  • Most cases of Lyme Disease can be treated successfully with a course of antibiotics, especially if caught early. Untreated, Lyme Disease can affect the joints, the heart and the nervous system and is much more difficult to treat.
Avoiding Ticks
  • To protect yourself against tick and insect bites:
    • walk on cleared trails wherever possible in areas of tall grass or woods;
    • wear light-colored clothing, tuck your top into your pants and tuck your pant legs into your boots or socks;
    • put insect repellent containing DEET on all exposed skin. Reapply as frequently as directed on the container;
    • check clothing and scalp (covered or not) when leaving an area where ticks may live;
    • check in folds of skin. Use good lighting and have someone help you check hard-to-see areas. When a tick is located, remove it immediately. Check the whole body! Don't stop when you find one tick, as there may be more;
    • regularly check household pets for ticks.
What To Do If You Find a Tick on Your Skin or Scalp
  1. Use tweezers or forceps to gently get a hold of the tick as close to the skin as possible. Don't touch the tick with your hands.
  2. Without squeezing the tick, steadily lift it straight off the skin. Avoid jerking it out. Try to make sure that all of the tick is removed.
  3. Once the tick has been removed, clean the bite area with soap and water then disinfect the wound with antiseptic cream. Wash hands with soap and water.
  4. If possible, save the tick in a container with a tight fitting top. If the tick is alive, dampen a small cotton ball with water and put it into the container to keep the tick alive. (A live tick is necessary for culturing the bacteria that causes Lyme Disease.) Label the container with the date, name and address of person bitten or what type of animal the tick was from, what part of the body was bitten, and what part of the province the tick probably came from. Also include the name and address of your family physician.
  5. Ask your doctor for further advice.

For laboratory testing, this container should be mailed as soon as possible to: BCCDC Laboratory Services, Parasitology Section, 655 West 12th Ave., Vancouver V5Z 4R4 BC Canada
 
Further Reading
Return to Manual Home Page Disease List - Body Region Affected Disease List - Causative Agent or Risk Factor Disease Surveillance Form Glossary Contact Information
Return to Manual Home Page Return to Disease List - Body Region Affected Return to Disease List - Causative Agent or Risk Factor Disease Surveillance Form Download Glossary Contact Information