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Lyme disease is a bacterial infection spread by ticks. You can get Lyme disease if you're bitten by an infected tick. But most people who've had a tick bite don't get Lyme disease. If you don't treat Lyme disease, it can lead to problems with your skin, joints, heart, and nervous system.
Lyme disease is caused by a bacteria. Infected ticks spread the bacteria by biting people or animals.
Two types of ticks carry the Lyme disease bacteria in Canada. They are:
Dogs, cats, and horses can become infected with Lyme disease bacteria, but they can't pass the illness to humans. But infected ticks may fall off the animals and then bite and infect humans.
To help prevent Lyme disease, cover up as much skin as you can when you will be in wooded or grassy areas. Wear a hat, a long-sleeved shirt, and long pants with the legs tucked into your socks. Use a bug repellent with DEET that can keep away ticks.
One sign of Lyme disease is a round, red rash that spreads at the site of a tick bite. This rash can get very large. Flu-like symptoms are also common. If Lyme disease goes untreated, you can develop swelling and pain in your joints, plus problems with your heart and nervous system.
Your doctor will ask questions about your symptoms and do a physical examination. The round, red rash is a sign of Lyme disease. Your doctor will also ask questions to find out if you've been around infected ticks. You may have a blood test to see if you have certain antibodies in your blood.
Lyme disease is treated with antibiotics. If Lyme disease goes untreated, it can lead to problems with your skin, joints, nervous system, and heart. The problems often get better with antibiotics. But in rare cases, they can be lifelong.
The symptoms of Lyme disease depend on the stage of the disease. You may first notice symptoms weeks to months after the tick bite. If the disease isn't treated, it may progress from mild symptoms to serious, long-term disabilities.
If you don't have symptoms during stage 1, your first symptoms may be those found in stage 2 or 3.
Call your doctor if:
To diagnose early Lyme disease, your doctor will give you a physical examination. You will be asked about your symptoms and any recent exposure to ticks. The clearest sign of infection is an expanding, circular red rash. (This is called erythema migrans.)
Your doctor may do blood tests to confirm that you have Lyme disease. The decision about when to use blood tests depends on if your doctor strongly thinks you have Lyme disease and if the test results will change your treatment. In some cases, your doctor may treat you for Lyme disease without doing any tests.
Lyme disease is often hard to diagnose. Early on, blood tests may not show Lyme disease even though you are infected. At later stages, blood tests may not be able to tell if you have an active infection or a past infection that you recovered from. The symptoms of chronic Lyme disease can be very similar to other illnesses. People may test positive even though something other than Lyme disease is causing their symptoms.
Lyme disease is treated with antibiotics. Most people are treated with antibiotics that are taken by mouth. But sometimes antibiotics through a vein (IV) are needed.
It's important to get treatment for Lyme disease as soon as you can. If it goes untreated, Lyme disease can lead to problems with your skin, joints, nervous system, and heart. These can occur weeks, months, or even years after your tick bite. The problems often get better with antibiotics. But in rare cases, they can last the rest of your life.
Even after successful treatment for Lyme disease, you can get it again. So it's important to keep protecting yourself against tick bites.
Current as of: July 1, 2021
Author: Healthwise StaffMedical Review: E. Gregory Thompson MD - Internal MedicineAdam Husney MD - Family MedicineKathleen Romito MD - Family MedicineChristine Hahn MD - EpidemiologyW. David Colby IV MSc, MD, FRCPC - Infectious Disease
Current as of: July 1, 2021
Author: Healthwise Staff
Medical Review:E. Gregory Thompson MD - Internal Medicine & Adam Husney MD - Family Medicine & Kathleen Romito MD - Family Medicine & Christine Hahn MD - Epidemiology & W. David Colby IV MSc, MD, FRCPC - Infectious Disease
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