Anaplasmosis
Anaplasmosis is caused by a bacterium transmitted primarily by the bite of an infected blacklegged tick (Ixodes scapularis - see photo) or western blacklegged tick (Ixodes pacificus).
Most people infected with the bacteria develop fever and mild non-specific symptoms such as chills, headache and muscle aches. In most cases Anaplasmosis infection is mild, however older individuals and those with compromised immune systems may develop more severe illness and require hospitalization. Anaplasmosis infection can be successfully treated with antibiotics. Risk of infection can be lowered by preventing tick bites.
Image Content Provider: James Gathany US CDC PHIL
Symptoms
Anaplasmosis symptoms generally appear 5 – 21 days following the bite of an infected blacklegged tick. The first symptom is typically fever, followed by one or more of the common symptoms including chills, headache, muscle aches and joint pain. Older individuals and those with compromised immune systems may develop more severe illness with respiratory complications, opportunistic infections, neurological complications and kidney failure. Most cases are mild and self-limiting with all symptoms typically resolving within most patients within 30 days. However, those with severe illness often require hospitalization and fatalities are possible.
Blacklegged ticks can also transmit other infections, such as Babesiosis and Lyme disease. Co-infection with either of these may result in symptoms that are more severe and/ prolonged.
Causes
Anaplasmosis infection is caused by a bacterium, Anaplasma phagocytophilum. In North America Anaplasmosis infection normally cycles between small mammals, such as mice, and blacklegged ticks. Humans can become infected when bitten by an infected blacklegged tick. The highest risk period, May – July coincides with the peak activity of blacklegged tick nymphs.
Less common transmission methods of Anaplasmosis infection include mother to child, blood and/ or blood product transfusions and from handling infected animals (i.e. deer).
Treatment
Antibiotic treatment is started based on a physician’s suspicion of infection. Fever typically resolves within 24 – 48 hours after treatment is started. Most symptoms resolve within 30 days of the onset of symptoms. For those with more severe symptoms the recovery period may be longer.
Prevention
Restricting exposure to potentially infected blacklegged ticks is the key to preventing Anaplasmosis.
The risk of encountering potentially infected blacklegged ticks is greatest in blacklegged tick risk areas where surveillance has revealed established tick populations. Outside of these areas the likelihood of encountering blacklegged ticks is significantly lower. Blacklegged ticks are most commonly found in wooded or forested areas, or along the fringes of such areas, as these locations provide them with a suitable humid habitat in which to survive.
When active in these areas it is important to adopt preventative measures such as:
- Use trails, whenever possible, and stay to the centre of hiking trails or paths,
- Wear light coloured long pants and long sleeved shirts,
- Tuck in clothing (pants and socks) to create a barrier,
- Use an appropriate tick repellent.
Perform a thorough tick check after spending time outdoors inspect yourself, your children and your pets for blacklegged ticks and remove any found as soon as possible. Do not stop if you find one tick, as there may be more. Bathing soon after coming indoors is a good way to find any ticks. Be sure to check clothing and items such as backpacks which may have come into contact with vegetation as well. Finding and removing ticks in a timely manner can significantly reduce the likelihood of disease transmission.
Manitoba Health Resources
For the Public
Materials can be requested by visiting Health Information Resources and completing the attached form.
- Click here to access the eTick platform, including links to download the free mobile eTick app in both the Google Play or App stores.
- Tick-borne Diseases & Children
Tips for parents, guardians and those working with children to reduce the potential for transmission of tick-borne diseases. - Tick Bite Prevention, Tick Checks and Tick Removal Postcard
Quick reference tool with tips for tick-bite prevention, tick checks and tick removal. - Tick Bite Prevention and Tick Removal – Quick Reference Card
Wallet sized card with tick-bite prevention and tick removal tips. - Landscape Tips to Reduce Ticks
Quick reference tool with tips to make yards less welcoming to ticks and their hosts (ex. mice and deer).
For Health Care Providers
- Tick-borne disease Quick Reference Guide for Health Care Providers NEW
- Tick Collaborative Care Service (TiCCS) – provincial care service for diagnosing and managing cases of possible late Lyme and/ or other emerging tick borne diseases (referral required)
- Tick-borne Infections in Manitoba - Update for Health Care Providers
May 20, 2021 - Tick-borne Disease Clinical Case Report Form
- Anaplasmosis Communicable Disease Management Protocol
- Archived updates related to Tick-Borne diseases can be found here
Other Resources
- Anaplasmosis – U.S. Centers for Disease Control and Prevention
- Tick-borne diseases of the United States – Reference Manual for Health Care Providers (U.S. Centers for Disease Control and Prevention)
- Additional resources - Emerging Tick-Borne diseases, surveillance, prevention and travel
Communicable Disease
Control (CDC) Health Links – Info Santé |
