Lyme Disease
Question: I have heard that Lyme disease is becoming more common in Canada, especially in the Maritimes where we live. Every summer, our family spends several weeks in the woods; we enjoy it very much. I am worried about this Lyme disease, after hearing some horrible stories in the media. I am considering cancelling our camping trip this year. Is there any way that we can prevent getting infected?
Answer:
It is true that Lyme disease is becoming more common in Canada, especially in the Maritimes. However, if you exercise precaution, you can reduce the chance of infection and enjoy the beautiful outdoors during our short Canadian summer.
Lyme disease is a bacterial infection caused by a spiral-shaped bacterium called Borrelia. It is spread by the Ixodes ticks, also known as deer or blacklegged ticks. These are mostly found in northeastern United States and in midwest, but with global warming, they have been spreading north into the Maritimes and Ontario. In some places, as much as half of the ticks are infected with Borrelia.
Fortunately, the risk of contracting Lyme disease is very low. Extensive research was conducted mostly in United States in the last two decades. An infected tick has to bite and attach to our skin for at least 72 hours before infection can begin; the Borrelia germs have to migrate from the tick’s intestine to the salivary glands and then injected into our body.
After infection, most will develop fever, headache, muscle ache and a typical rash after around 7 days, although this can be delayed for 30 days. The rash is called erythema migrans (EM). It is round in shape, at the site of tick bite, and gradually increase in size to over 5 cm, sometimes with a clear centre. There is no pain or itching, therefore, it can be unrecognized if it is on the back or behind the knees. The rash can disappear after several weeks.
When untreated, the infection can spread to the heart, the brain, and the joints. Some develop abnormal heart rhythm and inflammation of the heart, others can have paralysis of facial muscles and meningitis. The knees are the most commonly infected joints. Prompt antibiotic treatment can result in complete recovery.
The best way to prevent Lyme disease is to avoid being bitten by ticks. These are found in wooded areas with dense shrub, and they require moisture to survive. Camping in drier areas away from the forest can reduce the chance of infection.
Wear long-sleeve clothing that covers extremities, as well as head and neck, can reduce the chance of tick bite. Pants should be tucked into boots or socks; long-sleeve shirts should be buttoned at the cuff. Chemicals like DEET and Permethrin can be sprayed on clothing to repel both ticks and mosquitoes.
After hiking, all clothing should be removed and washed. Putting them in the dryer with high heat for one hour will kill the ticks. Take a shower to wash off any unattached ticks. Inspect each other’s body for ticks, especially in the head and neck, behind the ears, and on the back. Ticks that have attached for a short time may not be engorged; they can be small and difficult to find.
If ticks are found attached to the skin, they should be removed right away. Curved forceps or tweezers should be used to grasp the tick as close to the skin as possible, and pulled straight out without twisting. The idea is to remove the mouthpart of the tick with the body. If the mouthpart breaks off, it needs to be removed also, otherwise it can still transmit Lyme disease. Wash the skin with soap and water afterwards.
The sooner you remove any attached ticks, the less likely you can get infected. If there is confirmed tick bite, you should consult your doctor for prophylactic antibiotics. If you develop symptoms of early infection and EM rash, prompt treatment with antibiotics can eradicate the Borrelia bacteria.
If you have a dog, consult your veterinarian for products that can prevent tick bite, and check for ticks daily. You shouldn’t be afraid to enjoy nature because of Lyme disease. Take the necessary precautions and enjoy our short sweet summer.