COVID-19

COVID-19 is a potentially severe viral infection that mostly affects your lungs and airways.

• It's caused by a coronavirus

• The virus spreads very easily to other people

• Some infected people have no symptoms, but others get very sick, and some people die

• Swabs from your nose or throat are tested to diagnose COVID-19

• No medicines cure COVID-19, but some might help people with severe infection or people at risk of severe infection

• The best way to prevent COVID-19 is to be vaccinated

COVID-19 is caused by a type of coronavirus called SARS-CoV-2. The virus spreads:

• Mostly through the air, in droplets that an infected person spreads through a cough, sneeze, singing, or talking

• Through touching things that infected people have touched and then touching your face

You can spread the virus that causes COVID-19 before you have any symptoms.

Also, COVID-19 spreads from person to person much more easily than other respiratory infections like colds or the flu.

Many people with COVID-19 have almost no symptoms.

If you do get symptoms, you'll likely have:

• Fever

• Dry cough

• Trouble breathing

• Feeling really weak and tired

You may also have:

• Runny nose

• Sore throat

• Loss of your sense of smell and taste

• Headaches

• Stomach problems such as nausea, vomiting, and diarrhea

A bad infection goes into your lungs, causing viral pneumonia. That will make you very short of breath. A bad infection can also affect a lot of organs, including your brain, heart, and kidneys.

You should be tested for COVID-19 if you:

• Have symptoms of COVID-19—you should isolate while awaiting test results

• Were exposed to a person with COVID-19 (you are a "close contact")—get tested around 5 days after your last contact

• Were asked to get tested for a workplace, school, or community screening, particularly if you are not fully vaccinated

The most common test that a doctor or other healthcare worker does, called a PCR test (polymerase chain reaction test), uses:

• A swab taken from your nose or throat

The swab is sent to a lab to look for the virus or other evidence of an infection. It can take a few days to get your results.

Antigen tests are a different type of test than a PCR test. Antigen tests can be done at home or in a healthcare setting and uses a swab taken from your nose. They are generally less accurate than PCR tests. But antigen tests can provide rapid results (within 15 minutes).

A blood test can look for antibodies your body has made to defend against the virus. It takes your body a few weeks to make these antibodies, so this test is not useful when you first get sick. But it can help tell whether you were ever infected.

If you have a mild or moderate case, you'll:

• Stay home and not go out or go near other people (isolation)

• Wear a mask so you don't spread the virus

If you have a severe case, with breathing problems, you'll need to go to the hospital. Doctors will:

• Give you oxygen

• Sometimes, give you medicines

• Sometimes, put you on a ventilator (machine to help you breathe)

You may need to be on a ventilator for up to a few weeks.

If you have problems with your kidneys, you may need dialysis.

The best way to prevent COVID-19 is to be vaccinated. The Centers for Disease Control and Prevention (CDC) recommends that people aged 6 months and older receive the 2023–2024 updated COVID-19 vaccine to protect against serious illness from COVID-19 (see [CDC]: Vaccines for COVID-19). 

• The vaccines are safe and effective

• You can't get COVID-19 from a COVID-19 vaccine

• Vaccine effectiveness can decrease over time, so it's important to stay up to date on vaccinations

• COVID-19 vaccines can cause mild side effects (a sore arm, body aches, headache, fever) for a day or two

• You should get a COVID-19 vaccine even if you had a COVID-19 infection

In addition to being vaccinated, you should avoid being exposed to the virus. That can be difficult. People who can spread the virus may not have any symptoms, so you can't tell who has it and who doesn't. The CDC recommends additional ways to help avoid the virus in the CDC's Respiratory Virus Guidance.

You should wear a well-fitting face mask, covering both mouth and nose:

• You or the people around you have risk factors for severe illness.

• You or the people around you were recently exposed to a respiratory virus, are sick, or are recovering.

• Respiratory viruses are causing a lot of illness in your community.

Consider wearing a face mask when on public transportation (for example, planes, buses, trains) and while indoors at transportation hubs (for example, airports, train stations).

In addition to being up to date with vaccinations and wearing a mask:

• Get tested if you have symptoms of COVID-19

• Avoid crowded places and indoor spaces that do not have fresh air from the outdoors, if you're at higher risk of getting very sick from COVID-19

• Maintain good social distance from other people if you aren't up to date with vaccinations, especially if you're at higher risk of getting very sick with COVID-19

• If possible, maintain good social distance from a person who is sick with COVID-19 

• Wash your hands often with soap and water for at least 20 seconds

• Use an alcohol-based hand sanitizer

• Avoid touching your eyes, nose, and mouth with unwashed hands

• Stay home when you're sick

• Cover a cough or sneeze with a tissue, then throw the tissue in the trash

• Clean and disinfect frequently touched objects and surfaces using a regular household cleaning spray or wipe

• Pay attention to your health and watch for symptoms

1. CDC: Vaccines for COVID-19

2. CDC: Respiratory Virus Guidance