There are two types of ticks that can spread Lyme disease in Canada, the blacklegged or deer tick, Ixodes scapularis in southeastern and south-central regions of Canada western and the blacklegged tick Ixodes pacificus in British Columbia. Ticks become infected with Lyme disease bacteria by feeding on infected wild animals, such as birds and rodents. Once infected, ticks can spread the bacteria to humans and pets.
In most cases, the infected tick must attach and feed for at least 24 hours before the bacteria can be transmitted.
Most humans are infected through the bite of immature ticks called nymphs that are approximately the size of a poppy seed. Adult ticks approximately the size of a sesame seed can also spread Lyme disease. Early symptoms include a small, red bump that appears at the site of a tick bite or tick removal and resolves over a few days. This is normal after a tick bite and does not indicate Lyme disease. However, these signs and symptoms may occur within a month after infection:.
From 3 to 30 days after an infected tick bite, an expanding red area might appear that sometimes clears in the center, forming a bull's-eye pattern. However, pets can bring infected ticks into your home or yard. Consider protecting your pet, and possibly yourself, through the use of tick control products for animals. You will not get Lyme disease from eating venison or squirrel meat, but in keeping with general food safety principles, always cook meat thoroughly.
Note that hunting and dressing deer or squirrels may bring you into close contact with infected ticks. There is no credible evidence that Lyme disease can be transmitted through air, food, water, or from the bites of mosquitoes, flies, fleas, or lice. Ticks not known to transmit Lyme disease include Lone star ticks Amblyomma americanum , the American dog tick Dermacentor variabilis , the Rocky Mountain wood tick Dermacentor andersoni , and the brown dog tick Rhipicephalus sanguineus.
How ticks find their hosts. How ticks attach to their hosts. The tick feeding process makes ticks very good at transmitting infection: Depending on the tick species and its stage of life, preparing to feed can take from 10 minutes to 2 hours. When the tick finds a feeding spot, it grasps the skin and cuts into the surface. The tick then inserts its feeding tube. Many species also secrete a cement-like substance that keeps them firmly attached during the meal. The feeding tube can have barbs, which help keep the tick in place.
If the tick is in a sheltered spot, it can go unnoticed. A blacklegged tick will attach to its host and suck the blood slowly for several days. If the host animal has certain bloodborne infections, such as the bacteria that cause Lyme disease, the tick may ingest the pathogen and become infected.
Mark Schmiedl. Symptoms from tick bites with tick-borne diseases such as Lyme disease include:. If you see a tick crawling on your skin, and if it bites you, the best thing to do is get rid of it safely. Use a pair of tweezers to clench the tick as close to your skin as possible. Pull up with the tweezers using gentle yet steady pressure. After removing the entire tick, use rubbing alcohol or soap and water to clean the tick bite. Some people attempt to get the tick to come out on its own, rather than remove the tick with tweezers.
I do not recommend these strategies. The quicker your can safely remove the entire tick, rather than waiting for it to come out on its own, the lower your odds of contracting a tick-borne illness such as Lyme disease. Nymphs and larvae are typically found in layers of decomposing leaves underneath trees. Ticks thrive in damp environments and are less active in hot, dry weather. Nymphal ticks cause most cases of Lyme disease. Adult ticks can also infect humans, but are easier to spot and remove.
Not all ticks are infected. Because tick studies have only been done in a relatively few places, in most of the US, tick infection rates are unknown. Even in places where ticks generally do not carry Lyme, there may be hotspots of infection depending on local conditions. The tick infection rate may also change from year to year, even in one location. To get a better idea of which tick-borne diseases have been found in your area, check this site.
Adult ticks feed and mate primarily on deer. You may also find adult ticks on dogs, horses and other domesticated animals. Nymphs feed primarily on smaller animals. These include squirrels, mice, lizards, rabbits, and birds that feed on the ground. Migratory birds help distribute ticks throughout the country.
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