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Anaplasmosis is an infection caused by the bacteria Anaplasma phagocytophilum. Humans can become infected with this bacterium when they are bitten by an infected blacklegged tick, also known as a deer tick. This type of tick is found throughout Ontario, including the Northwestern Health Unit region. Blacklegged ticks are very small and hard to see. Not all blacklegged (deer) ticks carry the bacterium that causes Anaplasmosis.

Symptoms of Anaplasmosis usually begin within five days to three weeks of being bit. The symptoms include: fever, headache, chills, muscle and joint pain, fatigue and nausea. Less common symptoms include abdominal pain, vomiting, cough and confusion. A rash is rarely noticed. Anaplasmosis is most often a mild and self-limiting illness. More serious infections and complications may occur in people who have weak immune systems or in older adults. 

Risk of Anaplasmosis
The risk of getting Anaplasmosis depends on the risk of being bitten by a blacklegged tick that can carry the bacteria for Anaplasmosis.

The risk of being bitten by any blacklegged tick mainly depends on the activities of the person. A person is more likely to be bitten by a blacklegged tick if walking through a wooded or bushy area and if not wearing protective clothing or using an appropriate insect repellant.

The fall of 2017 was the first year that a small number of ticks in Kenora and the surrounding area tested positive for the bacteria that causes Anaplasmosis. It is uncertain whether ticks will continue to test positive. Further tick surveillance is required to determine if this is an ongoing risk for this area. If bitten, disease can be prevented by removing the tick within 12 to 24 hours.

Diagnosis and Treatment
Anaplasmosis is diagnosed by clinical signs and symptoms and blood testing. Early antibiotic treatment is recommended. If you have symptoms of Anaplasmosis, see your doctor. 


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