Psoriatic arthritis (PsA) is an inflammatory type of arthritis that causes stiffness, swelling, and joint pain. It often accompanies the skin condition psoriasis, although not everyone with psoriasis will develop PsA. It’s an autoimmune disease, which means the body’s immune system attacks its own healthy cells.
The cause of PsA isn’t clear, but genetics and your environment are thought to be contributing factors. If you have a family history of PsA, symptoms can develop from exposure to triggers like physical trauma or infection.
Influenza (flu) is a virus that leads to respiratory infection. It affects your nose, throat, and lungs. The illness commonly called “stomach flu” is gastroenteritis, which isn’t the same as influenza.
Symptoms of influenza include fever, aching muscles, cough, and fatigue. Unlike the common cold, the flu has a sudden onset and usually includes a fever. It often resolves on its own, but some people are at higher risk for complications, some of which can be serious.
Since autoimmune diseases like PsA involve your immune system attacking healthy cells, treatment often involves decreasing that extra immune system activity.
Medications that suppress your immune system can also make you more vulnerable to infections like the flu.
Infections trigger an inflammation response. That means that if you have inflammatory arthritis like PsA, a virus like the flu can trigger a flare.
If you’re taking immune-suppressing medications like biologics, you may have to discontinue their use while you have the flu so you’re better able to fight the infection. Going off of your treatment may worsen your PsA symptoms.
If you have PsA and you contract the flu, you’re also more likely to require hospitalization because of complications. These include:
- flu-related pneumonia
- respiratory infections
- heart attack
It’s important to take action to avoid the flu. Taking these precautions can help you stay healthy each flu season:
- Get a flu vaccine.
- Avoid contact with people who have the flu.
- Wash your hands regularly with soap and water for at least 20 seconds.
- Avoid touching your face.
- Disinfect high-touch surfaces like door handles and TV remotes.
- Ask your doctor about protective medication additions or changes.
- Get regular exercise.
- Eat a healthy diet.
- Take supplements that boost immunity, like vitamin D. Always check with your doctor before adding supplements to make sure they don’t interfere with your medication.
- Make sure you get enough sleep each night.
- Practice stress management.
There are two types of flu vaccine: an injectable and a nasal spray.
Only the injectable flu vaccine is safe for people diagnosed with PsA. It’s an inactivated vaccine, meaning it doesn’t contain any live virus material. It won’t cause the virus against which it protects, so it won’t trigger an arthritis flare or bring on flu symptoms.
Here’s what you should know about the two vaccine types:
- Injectable vaccine. The injectable flu vaccine contains purified influenza antigen from viral material that’s been grown in a lab and then killed. The antigen part of a virus is what triggers your immune system to respond and make protective antibodies against the virus. The injectable vaccine won’t give you the flu because the viral material used to make the antigens is no longer alive.
- Nasal spray vaccine. The nasal spray flu vaccine is a live attenuated influenza vaccine (LAIV), which means it uses live, but weakened virus material. This type of vaccine isn’t recommended for anyone who has an altered immune system. If you have PsA, you should take the injectable flu vaccine, not the nasal spray version.
Flu vaccine side effects are usually mild. They include:
- soreness, redness, or inflammation at the injection site
- low grade fever
- muscle aches
It takes about 2 weeks from your vaccination date to develop enough flu antibodies from the vaccine to protect you. This protection lasts about 6 months, although it declines as time passes.
Certain drugs and higher doses of steroids may interfere with vaccine effectiveness. You may benefit from a temporary doctor-supervised break from your medication while the flu vaccine takes effect.
Even when vaccinated, people diagnosed with PsA should continue to take additional flu prevention measures such as handwashing and improved nutrition.
People diagnosed with PsA are more likely to catch the flu and experience worsened flu symptoms, especially if they’re being treated with immunosuppressive medications.
Some PsA medications can interfere with the flu vaccine and make it less effective. Ask your doctor about the medications you take, and if you should take a temporary medication holiday when you get vaccinated.
The injectable version of the flu vaccine is safe for those who have an autoimmune disease like PsA because it contains non-live material. If you have PsA, you shouldn’t get the nasal spray flu vaccine, which has live but weakened viral material.
There are other steps you can take to stay well during flu season, including washing your hands, eating well, getting enough sleep, and avoiding contact with germs.