Coronavirus Disease 2019 (COVID-19)

Last Updated November 2021 | This article was created by editorial staff and reviewed by Robert "Chuck" Rich, Jr., MD, FAAFP


COVID-19 is a disease caused by a coronavirus call SARS-CoV-2.

What is a coronavirus?

A coronavirus is a virus that is found in animals and, rarely, can be transmitted from animals to humans and then spread person to person. In addition to COVID-19, other human coronaviruses have included:

  • The MERS virus, or Middle East respiratory syndrome.
  • The SARS virus, or severe acute respiratory syndrome, which first occurred in the Guangdong province in southern China.

What are the symptoms of COVID-19?

COVID-19 symptoms range from mild to severe. It takes 2-14 days after exposure for symptoms to develop. Symptoms may include:

  • Fever
  • Cough
  • Shortness of breath
  • Chills
  • Repeated shaking with chills
  • Muscle pain
  • Headache
  • Sore throat
  • New loss of taste or smell
  • Runny nose
  • Nausea

Those with weakened immune systems may develop more serious symptoms, like pneumonia or bronchitis. You may never develop symptoms after being exposed to COVID-19.

What causes a COVID-19 infection?

The COVID-19 virus can be spread through contact with certain bodily fluids, such as droplets in a cough. It might also be caused by touching something an infected person has touched and then touching your hand to your mouth, nose, or eyes.

Children and adolescents can get COVID-19 just as easily as adults and can transmit it to others.

How is COVID-19 diagnosed?

If you believe you have COVID-19, the first step is to get a test. Testing availability may differ depending on where you live. Check your local health department to see what locations near you are doing testing. This may include hospitals and pharmacies that offer drive-thru testing. This will allow you to stay in your car to prevent the possible spread of COVID-19. Depending on the location, someone may approach your car to collect a sample, or they may ask you to collect it yourself. Samples for COVID-19 viral tests are collected through nasal swabs. Depending on where you get your test, you may get your results the same day or you may have to wait a few days. Find out more about COVID-19 testing.

If you have or believe you have COVID-19, your doctor may suggest you self-isolate to prevent the spread of infection. It’s also important to remember that even if you get a negative test, you may still need to self-isolate if you have been exposed to COVID-19. This is because it can take time after exposure for your sample to show a COVID-19 infection.

Do I need to quarantine if I have been exposed to COVID-19?

If you have been exposed to COVID-19 and do not have symptoms, you should quarantine. The Centers for Disease Control and Prevention (CDC) strongly recommends a full 14-day quarantine. It gives you the lowest risk of spreading infection to others. However, the CDC recently gave some flexibility on quarantine length.

Keep in mind that local officials may determine quarantine requirements for different states or counties. Reducing the length of quarantine may not be an option in all areas. If you need to quarantine, you should follow any local requirements and recommendations.

More information about quarantine for COVID-19 is available on the CDC’s website.

Can COVID-19 be prevented or avoided?

Getting the COVID-19 vaccine can protect you – and others around you – from getting very ill from COVID-19. Follow local guidance on wearing a mask. Even if you wear a mask, you should still avoid people who are sick or be cautious in large crowds. Stay home if you are sick and talk with your doctor about getting tested. Cover your cough with a tissue, or cough into your upper sleeve or elbow. Do not cough into your hands.

Wash your hands often with soap and water for at least 20 seconds, especially after going to the bathroom, before eating, and after blowing your nose, coughing, or sneezing. If soap and water are not readily available, use an alcohol-based hand sanitizer with at least 60% alcohol. Avoid touching your mouth, nose, or eyes.

COVID-19 treatment

As with a cold or the flu, drink fluids and get plenty of rest. Symptoms of COVID-19 usually go away on their own. If symptoms feel worse than a common cold, contact your doctor. He or she may prescribe pain or fever medication.  If you are having trouble breathing, seek immediate medical care.

The FDA advises people to be cautious of websites and stores selling products that claim to prevent, treat, or cure COVID-19. Additionally, do not take any form of chloroquine, ivermectin or other medicines unless they have been prescribed for you by your family doctor. The Food and Drug Administration (FDA) has approved one drug, remdesivir, to treat COVID-19 for people at high risk of serious illness. Your physician will decide whether what is appropriate to treat your illness.

Is there a vaccine for COVID-19?

There are three vaccines for COVID-19. Pfizer-BioNTech has FDA approval while Moderna and Johnson & Johnson (Janssen) are authorized for emergency use in the United States. The CDC has recommended the Pfizer-BioNTech’s coronavirus vaccine for people 5 and older, and the Moderna and Johnson & Johnson vaccines for people 18 and older. To maximize protection, COVID-19 vaccine booster doses are now recommended for adults aged 18 and older.

Living with COVID-19

When possible, avoid contact with others when you are sick. It is also possible to spread the virus if you don’t have symptoms. Wearing a mask in public can prevent spreading the virus. It should cover your mouth and nose. Continue to keep 6 feet between you and others.

Questions to ask your doctor

  • What can I do to prevent my friends and family from getting COVID-19?
  • What over-the-counter medicines work best for my symptoms?
  • Am I at risk of complications if I get COVID-19?
  • What symptoms should I seek medical advice for?