Health experts are raising alarms about a growing number of anaplasmosis cases in humans. Black-legged ticks, the same culprits behind Lyme disease transmit this bacterial infection. (The Canadian Press)
Experts are urging Canadians to stay alert for symptoms of a tick-borne disease called anaplasmosis, which has been increasingly common over the past 15 years. This infection, caused by the bacteria Anaplasma phagocytophilum, is spread by ticks and can infect both humans and animals.
In the early 2000s, only a few cases of anaplasmosis were reported annually. However, recent years have seen up to 500 cases annually in areas where the ticks carrying the bacteria are found. These areas include Nova Scotia, Quebec, and Ontario, with some cases also reported in Manitoba and Alberta.
Heather Coatsworth, a research scientist at the Public Health Agency of Canada’s National Microbiology Laboratory, described anaplasmosis as the "new kid on the block" in an interview with Dr. Brian Goldman on CBC's The Dose. The first recorded case of anaplasmosis in Canada was in 2009.
Anaplasmosis symptoms start with fever, chills, headache, and fatigue. If left untreated, it can lead to severe issues like respiratory failure, anemia, liver disease, and even death, especially in immunocompromised individuals, children, and the elderly. The disease typically takes around 18 hours of feeding by an infected tick to transmit. It can also be spread through blood transfusions, organ donations, and possibly from mother to baby.
Comparatively, anaplasmosis shares early flu-like symptoms with Lyme disease, another tick-borne illness. Both are spread by black-legged and Western black-legged ticks, which can sometimes carry both diseases simultaneously. However, unlike Lyme disease, anaplasmosis does not cause a bull's eye rash at the bite site. Both diseases can be treated with the antibiotic doxycycline, and those treated for anaplasmosis usually recover without long-term effects like arthritis seen in some Lyme disease patients.
Currently, Lyme disease remains more prevalent than anaplasmosis, with around 2,500 cases reported in 2023, according to Health Canada. Nationwide statistics for anaplasmosis are not yet fully available as it only became a nationally notifiable disease in April 2024, requiring mandatory reporting to public health authorities.
To prevent anaplasmosis, experts recommend avoiding tick bites. Using bug sprays that target ticks, avoiding direct skin contact with grassy areas, and performing regular tick checks after spending time outdoors can help reduce risk. Ticks can be as small as a freckle but have legs, making them identifiable. If bitten, use tweezers to remove the tick and keep it for potential testing.
Wearing protective clothing, such as tucking pants into socks, wearing long sleeves, and treating clothes with permethrin, can also help prevent bites. Online tools like eTick can assist in identifying tick species and high-risk areas. If bitten, be vigilant for flu-like symptoms and seek medical help if they occur.
Despite the rise in tick-borne diseases, Canadians are encouraged to enjoy outdoor activities while taking precautions. "Get outside, enjoy it, and then do tick checks afterward," said Vett Lloyd, a biology professor at Mount Allison University who runs a tick lab.
