What is coronavirus (COVID-19)?

COVID-19 is a disease caused by a type of coronavirus. This illness was first found in December 2019. It has since spread worldwide.

Coronaviruses are a large group of viruses. They cause the common cold. They also cause more serious illnesses like Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome (SARS). COVID-19 is caused by a novel coronavirus. That means it's a new type that has not been seen in people before.

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 protect yourself?

Follow these guidelines until your doctor tells you it's safe to stop.

• Stay up to date on your COVID-19 vaccines.
• Talk to your doctor about how many doses you need.
• Avoid sick people.
• Talk to your doctor to see if you need medicine to lower your risk of getting COVID-19 or getting very sick from COVID-19.
• Wear a mask with the best fit, protection, and comfort for you if you go into public areas, especially indoor spaces.
• Avoid crowds. And try to stay 2 metres (6 feet) apart from other people. If you have to be in a crowded area, wear a mask. This is important even if you're outside.
• Wash your hands often.
• Avoid touching your mouth, nose, and eyes.
• Improve the airflow when you spend time indoors with people who don't live with you. If you can, open windows and doors. Or you can use a fan to blow air away from people and out a window.
• 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 visiting with them indoors.

If you think you've been exposed, or you're sick, call your doctor as soon as you can. You may need a COVID-19 test. Your doctor may want to give you medicine to help prevent severe COVID-19.