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Learning About Preventing COVID-19 When You Have a Weakened Immune System

What is COVID-19?

COVID-19 is a disease caused by a type of coronavirus. This illness was first found in 2019 and has since spread worldwide (pandemic). Symptoms can range from mild, such as fever and body aches, to severe, including trouble breathing. COVID-19 can be deadly.

Coronaviruses are a large group of viruses. Some types cause the common cold. Others cause more serious illnesses like Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome (SARS).

What causes a weakened immune system?

Your immune system may not work well because of certain medicines to treat cancer or autoimmune disease or ones needed after an organ transplant. Taking steroid medicines for a long time can also weaken your immune system. Other causes include certain health problems, as well as immune problems that run in your family.

Why is it important to take extra precautions?

A weakened immune system makes it more likely that you'll get very sick from COVID-19. And the COVID vaccine may not work as well for you.

How can you help protect yourself?

  • Take steps to reduce your risk of illness.
    • Stay up to date on your COVID-19 vaccines.
    • Wear a mask with the best fit, protection, and comfort for you if you go into public areas, especially indoor spaces.
    • Wash your hands often. And avoid touching your mouth, nose, and eyes.
    • Avoid sick people and crowds. If you have to be in a crowded area, such as an airport, wear a mask. This is important even if you're outside.
    • Choose outdoor visits and activities when possible. If you have to spend time indoors with others, open windows and doors. Or use a fan to blow air away from people and out a window.
  • Be prepared to act quickly.
    • Learn about medicines to reduce your risk of getting very sick from COVID-19. These include antiviral medicines.
    • Have COVID-19 tests available at home, or know where to get tested. If you have symptoms, get a test right away.
    • If you test positive for COVID-19 or you're sick, call your doctor right away. Medicines to reduce your risk of serious illness need to be taken in the first few days after you get sick. You may be able to get them from your doctor, a pharmacy, or a health clinic.
  • Get others to help protect you.
    • Ask the people you live with or who are in close contact with you to stay up to date on their COVID-19 vaccines.
    • Ask the people you live with to wear a mask in public areas. This is important even if they're up to date on their COVID-19 vaccines.
    • Ask people who don't live with you to get a COVID-19 test before you visit with them.

Where can you learn more?

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