Are ticks just a harmless nuisance?
Tick bites can present a temporarily annoying experience in the summertime. However, the additional possibility of catching Lyme disease is one more reason to take action against these bugs. Lyme disease is caused by a spiral-shaped bacterium called Borrelia burgdorferi, which is spread by the bite of ticks of the genus Ixodes, commonly known as deer ticks or black-legged ticks.
These ticks are tiny – about the size of a pinhead when immature – and grow only slightly bigger as adults. They crawl onto a person's skin from grasses and shrubs in wooded areas. The tick digs its mouth into the skin and feeds for 2 or 3 days before dropping off.
Although not necessarily confined to these specific areas, most cases of Lyme disease are reported in the northeastern US (from Massachusetts to Maryland), the north-central states (especially Wisconsin and Minnesota), and the west coast (particularly northern California). The disease is on the rise in the US, with approximately 20,000 cases every year, and also appears in Canada. From 1999 to the end of 2004, a total of 172 human cases of Lyme disease were reported in Ontario. Approximately 20 to 60 new cases of Lyme disease are reported every year in Canada.
Signs of Lyme disease
A characteristic sign of Lyme disease is a skin rash that starts with a small red patch that gradually expands, often clearing in the centre to form a "bull's-eye" pattern. The person may develop "flu-like" symptoms including fatigue, headache, chills, fever, muscle and joint pain, and swollen lymph nodes. Less commonly, tingling or numbness in the hands and feet or facial paralysis has also been reported.
Preventing tick bites
To avoid tick bites when hiking or camping in wooded areas:
- If possible, stay away from tick-infested areas, especially in May, June, and July.
- Stay in the middle of hiking trails and try not to brush against grasses or leaves.
- Wear light-coloured clothes to make it easy to spot ticks "hitching a ride" on you.
- Wear closed shoes and long pants with the pant legs tucked into your socks or boots. As an extra precaution, put tape around the area where your pants and socks meet.
- Wear a hat and a long-sleeved shirt for extra protection.
- Spray your clothes and exposed skin with an insect repellent that contains 30% DEET (also effective at repelling mosquitos, which can carry malaria or West Nile virus), or treat clothes with the insect repellent permethrin, which kills ticks on contact. If using DEET, never spray it directly on your face or broken skin. And, for children aged 6 months to 2 years, do not apply DEET on the face or hands.
If you spend several days outdoors in areas that might contain ticks, inspect yourself daily once you're indoors. Check your skin carefully for ticks, and ask someone to check your scalp for ticks. If a tick has already latched on to you, don't panic. Even if the tick has bitten you, remember that not all ticks carry Lyme disease.
The best way to remove a tick is with a tick-removing device or a pair of fine-point tweezers. Grasp it where its mouthparts enter the skin or, if that is not easily visible, grab it by its head (as close to your skin as possible) with the suggested removal tools. Pull the tick straight out firmly and steadily. Do not twist, squash, or crush the tick when you are removing it. Be patient, as proper tick removal takes time. If you notice that the tick's mouthparts still remain in your skin, don't worry; the bacteria that cause Lyme disease reside in the tick's gut or salivary glands.
Do not squeeze the tick's body, do not apply petroleum jelly or alcohol, and do not use a hot match, nail polish, or other products while the tick remains attached. These actions could transmit the Lyme-disease-causing bacteria to you.
Once you remove the tick, place it in a container (e.g., a small jar with a lid) with alcohol to kill and preserve it so you can take it to your doctor to check if it carried Lyme disease. Cleanse the affected area of your skin with an antiseptic (e.g., alcohol) or mild soap and water. Wash your hands thoroughly with soap and water. You should also have the tick bite examined by your doctor, especially if you develop a rash or flu-like symptoms.
Treating Lyme disease
For people who require treatment for a mild infection associated with Lyme disease, their doctor will usually prescribe an oral (by mouth) antibiotic for 14 to 21 days. These types of antibiotics include doxycycline, amoxicillin, or cefuroxime. The specific antibiotic used will depend on a person's medical history and medication allergies.
For people who require treatment for more severe infections associated with Lyme disease, their doctor will usually prescribe an intravenous (given through the vein) antibiotic (e.g., ceftriaxone, cefotaxime, penicillin) for 2 to 4 weeks. On occasion, treatment with an oral antibiotic may be prescribed following treatment with an intravenous antibiotic.
If the tick is identified and removed within 72 hours of the bite, and assuming that no skin rash has appeared, your doctor may consider prescribing a single oral dose of doxycycline. This treatment can help prevent the rash from developing.
If you have Lyme disease, your doctor will determine the most appropriate treatment for you.
Overall, when you are travelling abroad, especially to developing and tropical countries, it is a good idea to speak with your doctor or pharmacist about how to protect yourself from diseases. Aside from watching what you eat and drink and protecting yourself from tick bites, you also have to watch for many other diseases, such as malaria, hepatitis, influenza, and yellow fever. Many of these diseases can be prevented with immunizations, so speak to your doctor or visit a travel clinic to see if you are at risk and what immunizations you and your family would benefit from.