What Is Influenza?
Influenza (the flu) is a contagious respiratory illness caused by influenza viruses that infect the nose, throat and lungs. It is more severe and long lasting than the common cold. The flu spreads through droplets released when an infected person coughs, sneezes or talks, and less commonly through touching contaminated surfaces.
In North America, flu season typically peaks between December and February. Each year, multiple strains circulate. The annual flu shot contains inactivated (killed) influenza viruses, selected based on strains that were circulating previously and those expected to be most active in the upcoming season. It usually protects against influenza A (H1N1 and H3N2) and influenza B.
Why Is the Flu Shot Important for People With SLE?
People with SLE (lupus) and rheumatoid arthritis have weakened immune systems, both from their disease and from medications used to manage it. This increases the risk of serious illness from influenza.
Complications may include:
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More severe symptoms
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Higher risk of hospitalization
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Increased chances of secondary bacterial pneumonia
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More frequent infections than the general population
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Lupus flares triggered by infection
The flu shot can also reduce the risk of certain bacterial infections that may occur on top of influenza, such as secondary pneumonia. Preventing the flu also helps reduce missed time from work and other responsibilities.
How Can We Prevent Influenza?
Annual Flu Shot
The most effective way to prevent influenza is by receiving the annual flu shot. It lowers the risk of infection and helps the immune system respond more effectively, often resulting in milder illness if infection occurs.
Hygiene and Day-to-Day Prevention
Additional prevention steps include:
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Washing your hands regularly
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Avoiding touching your face
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Covering your mouth and nose when coughing or sneezing
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Staying home when sick
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Avoiding close contact with sick individuals
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Wearing a mask, especially if you take strong immunosuppressive medications
These strategies provide extra protection against influenza.
Should You Get the Flu Shot?
Almost everyone, especially immunocompromised people, is recommended to get the annual flu shot. It is safe, quick and effective at lowering the risk of infection and minimizing symptoms if influenza occurs.
The flu shot is also recommended if you are pregnant or breastfeeding.
Should I Get Other Vaccines?
Yes. Alongside your annual flu shot, staying up to date on other vaccines is important.
These include:
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HPV vaccine
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Shingles vaccine (Shingrix)
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COVID-19 vaccines and boosters
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Pneumococcal vaccines
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Tetanus/Tdap boosters
Follow vaccination guidelines for your age and province or territory.
Should I Hold My Immune Suppression Drugs When I Get the Flu Shot?
The majority of immunosuppressive drugs are safe to take while receiving your flu shot. The exception, rituximab, may inhibit the effectiveness of the influenza vaccine as it lowers the amount of lymphocyte B, restricting a humoral immune response, in other words your immune system’s ability to create antibodies to specifically fight influenza.
Your doctor may recommend:
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Timing the flu shot months after a rituximab infusion
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Allowing at least 2 weeks before the next infusion, when possible
Always follow your rheumatologist’s guidance on vaccine timing.
What Does Health Canada Say About Flu Shots?
Health Canada recommends annual flu shots be administered to individuals starting at 6 months of age.
It is highly recommended that persons over the age of 65, and persons with compromised immune systems receive their flu shot annually. Those who are 65 or older are recommended to receive high-dose or adjuvanted flu vaccines such as Fluzone High Dose Quadrivalent. If you are an adult under the age of 65, the usual flu shot used is either quadrivalent inactivated influenza vaccine (QIV) or recombinant influenza vaccine (RIV).
Will the Flu Shot Flare My Lupus?
While you may notice minor side effects from the flu shot, it is uncommon to receive a lupus flare from a flu shot. If your lupus does flares up from the flu shot it’s important to contact your physician.
How Is the Flu Shot Given?
The flu shot is given intramuscularly (into the upper arm). The process is quick, safe and well-tolerated.
Is the Flu Shot a Live Vaccine?
Most flu vaccines in Canada are inactivated (non-live) and safe for immunocompromised individuals. The live nasal spray flu vaccine is not recommended for people on immunosuppressive therapy.
Always inform your vaccination provider about your health status and medications.
How Effective Is the Flu Shot?
The flu shot does not prevent every case of influenza due to circulating strain variations, but:
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Illness is milder in vaccinated individuals
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Hospitalization risk is lower
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Complications are reduced
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Flares triggered by infection may be avoided
For people with SLE and rheumatoid arthritis, the flu shot is an important layer of protection.
Who Should NOT Get the Flu Shot?
Do not receive the flu shot if you have:
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A severe allergy to a vaccine ingredient
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A history of severe allergic reaction to a previous flu shot
Egg allergies are not a contraindication — most flu shots contain only trace amounts of ovalbumin, and egg-free options exist.
Discuss any concerns with your healthcare provider.
Authors: Daniel Tingey and Doctor Janet Pope
Note: Please consult your healthcare provider or local health authorities for up-to-date vaccine recommendations.