The classic symptoms of Lyme disease
Symptoms of Lyme disease vary greatly depending on a number of factors. First, they will differ according to the stage of infection. The disease has 3 main stages:
Lyme disease and persistent symptoms
The CDC now recognizes Lyme disease as an infection that can cause chronic symptoms. [4] While most people recover completely from Lyme disease after antibiotic treatment, some individuals may still experience persistent and debilitating symptoms. The most common symptoms include fatigue, muscle pain, and cognitive impairment. Studies published in The American Journal of Medicine (2010) and The Lancet Regional Health – Europe (2021) show that these persistent symptoms are 5% to 10% more common in people who have had Lyme disease, compared to those who haven’t, six months after treatment. Although the cause of these symptoms remains unknown, similar symptoms have been observed following other infections, including COVID-19.
While there is still no clear explanation for this phenomenon, a recent study has identified these possible factors as contributing to the persistence of infection. [5]:
Here is a partial list of symptoms that may appear in the acute phase of infection
The following is a chart for each system, including an extensive list of possible symptoms in the disseminated phase of the disease:
Head, face and neck
Eyes and vision
Ears and hearing
Digestive and excretory system
Musculoskeletal system
Respiratory and circulatory systems
Neurological system
General well-being
Psychological well-being
Cognitive skills
Reproduction and sexuality
The co-infections
In addition to the Borrelia burgdorferi bacterium, ticks often carry other pathogens. Symptoms and clinical manifestations of each of these infections can either resemble or differ from those of Lyme disease, making diagnosis and treatment extremely difficult. In Quebec, babesia and anaplasma are the most common pathogens, but can also include many others.
Distinctive symptoms of co-infections
Other tick-borne infections in Quebec include:
- Anaplasmosis
- Babesiosis
- Powassan virus
- Tick-borne relapsing fever
Anaplasmosis: an infection on the rise in Quebec
Anaplasmosis is a bacterial infection transmitted by the same tick that causes Lyme disease.
Since 2021, it has become the most frequently diagnosed tick-borne co-infection in Quebec.
The majority of cases were in the Eastern Townships and Montérégie.
This trend shows that this infection is becoming increasingly important in the surveillance of tick-borne diseases in Quebec.
Like Lyme disease, anaplasmosis is probably under-diagnosed, which means that many cases go unnoticed. The actual number of people affected could therefore be much higher than official figures show.
Symptoms
Anaplasmosis can be transmitted rapidly after a tick bite, sometimes in less than 24 hours.
The first signs generally appear between 5 and 21 days after the bite, which is often painless and goes unnoticed.
The most frequent symptoms are:
- Sudden fever
- Chills
- Severe fatigue
- Headaches
- Muscle and joint pain
- General discomfort
Other possible symptoms may include:
- Stiff neck
- Nausea
- Coughing
- Anemia
On rare occasions, especially in elderly or immunocompromised individuals, or in cases of late diagnosis, anaplasmosis can cause serious complications such as generalized infection (sepsis), respiratory problems, cardiac or neurological damage, and even kidney failure.
Diagnosis
The diagnosis is generally based on symptoms and exposure history (tick bite, outdoor activities, etc.).
Available tests (such as PCR tests or antibody tests) can help confirm infection, but some can take several days to provide results.
Treatment should therefore be started as soon as anaplasmosis is suspected, especially if the person has a fever after possible exposure to a tick.
Treatments
Anaplasmosis is effectively treated with antibiotics, usually doxycycline. This treatment is recommended for adults and children, and symptoms often improve quickly.
In case of allergy, intolerance, or pregnancy, other options may be considered, depending on the doctor’s advice.
⚠️ Treatment should be started promptly, without waiting for test results, as soon as anaplasmosis is suspected. This helps prevent complications, especially in more vulnerable people.
Babesiosis
Babesiosis is an infection caused by a parasite that attacks red blood cells, much like malaria.
It is mainly transmitted by the bite of the Ixodes scapularis tick, the same tick responsible for Lyme disease.
Since 2004, babesiosis has been reportable in Quebec.
As with several tick-borne co-infections, we believe this infection is largely underdiagnosed, partly because symptoms are often unclear or confused with other diseases, and tests are not always performed in clinics.
Symptoms
Symptoms of babesiosis usually appear between 1 and 4 weeks after the bite, but sometimes it can take up to 9 weeks.
Some people can remain symptom-free, particularly if they’re healthy, but the disease can be serious in more vulnerable individuals (the elderly, immunocompromised, or those without a spleen).
Common symptoms:
- Fever, chills, sweating
- Fatigue, weakness
- Headaches, muscle or joint pain
- Nausea, loss of appetite
- Dry cough, sore throat
- Sensitivity to light (photophobia)
- Weight loss, mood swings, depressive symptoms
Possible symptoms in case of more severe infection:
- Yellowing of the skin or eyes (jaundice)
- Dark urine
- Shortness of breath, low blood pressure
- Liver, kidney or spleen damage
- Coagulation or neurological disorders
- In extreme cases: risk of multiple organ failure
Diagnosis
Diagnosis can be difficult because the symptoms are similar to those of other infections. It is suspected mainly in people with a tick bite, who have travelled to a high-risk area, or who have recently received a blood transfusion (babesiosis can also be transmitted this way).
The main test consists of examining a blood smear under a microscope. Further analysis (such as PCR testing) may be carried out if results are unclear.
Treatments
Babesiosis can be treated with appropriate medication, but the treatment is different from Lyme disease because it is caused by a parasite rather than bacteria.
In most cases, antiparasitic drugs are prescribed. Treatment choices will vary based on several factors, such as the severity of symptoms, overall health, and the presence of underlying conditions (e.g., weakened immune system).
Hospitalization may be necessary for closer monitoring in more severe cases or in more vulnerable individuals.
The Powassan virus
Powassan virus is a virus transmitted by certain ticks, including the black-legged tick (Ixodes scapularis) found in Quebec.
Although this infection is rare, it can sometimes lead to serious disease of the nervous system, such as encephalitis (inflammation of the brain).
Discovered in Ontario in 1958, this virus is now circulating in certain regions of Canada. Since 2020, ticks carrying the virus have been identified in Quebec, and in 2023, the first locally acquired case of encephalitis attributed to Powassan virus was reported.
Symptoms
Most infected people have no symptoms, or only mild flu-like symptoms. If symptoms appear, it’s usually between 1 and 5 weeks after the bite.
Possible symptoms:
- Fever
- Chills
- Fatigue
- Headaches
- Vomiting
- General weakness
In some cases, the infection can progress to a more severe form, affecting the brain or meninges. This can lead to:
- Confusion, loss of coordination
- Difficulty speaking
- Convulsions
- Paralysis
- Coma (in the most critical cases)
Among those who developed encephalitis:
- Approximately 10% died
- About half have permanent neurological damage, such as memory problems, muscle weakness, or partial paralysis.
Diagnosis
Diagnosis is based on the evaluation of symptoms and the context of exposure (e.g. tick bite, trip to a high-risk area). If Powassan virus infection is suspected, a blood or cerebrospinal fluid sample may be tested for antibodies or viral genetic material.
Treatments
There is no treatment or vaccine for Powassan virus.
If symptoms are mild, rest, hydration and medication to relieve fever or headaches may suffice.
In more serious cases, hospitalization may be necessary to monitor the person and support vital functions (such as breathing).
The body must fight the virus on its own, with the help of supportive care if necessary.
Tick-borne relapsing fever
Tick-borne relapsing fever is an infection caused by a bacterium of the Borrelia type. It is spread by the bite of certain ticks, including the black-legged tick (Ixodes scapularis), which is found in Quebec.
In recent years, a species called Borrelia miyamotoi has been considered emerging in Canada, particularly in regions such as the Eastern Townships, the Laurentians, and the Montérégie.
Like many other tick-borne diseases, it is probably under-diagnosed.
Symptoms
Symptoms often begin suddenly, with:
- High fever
- Chills
- Headaches
- Muscle or joint pain
- Fatigue
- Sometimes: vomiting, red eyes, rash, delirium
A particular feature of this disease is that it can cause several episodes of fever, which recur in cycles, spaced a few days apart. These relapses can occur up to 30 times if the infection is left untreated.
In some cases, complications may arise, such as:
- Yellowing of the skin (jaundice)
- Neurological disorders (meningitis, confusion)
- Heart, liver or spleen problems
These severe forms mainly affect vulnerable people, such as infants, the elderly, pregnant women and immunocompromised individuals.
Diagnosis
The diagnosis of Borrelia miyamotoi relapsing fever is based on an integrated assessment of exposure risk factors, clinical presentation (fever accompanied by at least one of the following symptoms: chills, headache, muscle or joint pain, fatigue), and laboratory test results.
Treatments
While no official treatment has yet been validated by clinical trials, this infection generally responds well to antibiotics used for Lyme disease.
Bartonellosis
Bartonellosis is an infection caused by a bacterium of the Bartonella type. While not transmitted by ticks, it can cause symptoms similar to those of Lyme disease or other co-infections. That’s why we’ve chosen to include it in this fact sheet.
There are two main forms of bartonellosis:
- Cat scratch disease, caused by Bartonella henselae
- Trench fever, caused by Bartonella quintana
Some forms can become opportunistic, meaning that they mainly affect people whose immune systems have been weakened (by illness, treatment or difficult living conditions).
Bartonella henselae – Cat scratch disease
- Transmitted by a cat scratch or bite, especially in kittens.
- Sometimes transmitted by cat fleas, even without direct contact with a cat.
Symptoms:
- Small wound at scratch site
- Swollen lymph nodes
- Mild fever
In rare cases, it can affect organs (eyes, liver, heart, brain), especially in immunocompromised people.
Bartonella quintana – Trench fever
- Transmitted by body lice
- Mostly observed in people who are homeless or living in very precarious conditions
Symptoms:
- Fever (often returns in cycles)
- Leg or back pain
- Fatigue, headaches
- In severe cases: damage to liver, spleen, heart or brain
Things to remember
- Bartonellosis can go undetected or be confused with other diseases, such as Lyme disease.
- It is probably under-recognized and under-diagnosed.
- It’s worth considering, especially when symptoms persist for no obvious reason.