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Coronavirus disease 2019 JH 02/22/21 Edited Article

Coronavirus - 2019; Coronavirus - novel 2019; 2019 Novel coronavirus; SARS-CoV-2

TEST for EDIT CONTENT email notification. JH 02/22/21

Coronavirus disease 2019 (COVID-19) is a respiratory illness that causes fever, coughing, and shortness of breath. COVID-19 is highly infectious, and it has spread throughout the world. Most people get mild to moderate illness. Older adults and people with certain health conditions are at high risk for severe illness and death.

 

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Causes

COVID-19 is caused by the SARS-CoV-2 virus (severe acute respiratory syndrome coronavirus 2). Coronaviruses are a family of viruses that can affect people and animals. They can cause mild to moderate respiratory illnesses, such as the common cold. Some coronaviruses can cause severe illness that can lead to pneumonia and even death.

COVID-19 was first reported in Wuhan City, Hubei Province, China in early December, 2019. Since then, it has spread throughout the world and within the United States.

SARS-CoV-2 is a betacoronavirus, like the MERS and SARS coronaviruses, which both originated in bats. It is thought that the virus spread from animals to humans. Now the virus is mainly spreading from person-to-person.

COVID-19 spreads to people within close contact (about 6 feet or 2 meters). When someone with the illness coughs, sneezes, sings, talks, or breathes, droplets spray into the air. You can catch the illness if you breathe in these droplets or they get in your eyes.

In some instances, COVID-19 may spread through the air and infect people who are more than 6 feet away. Small droplets and particles can remain in the air for minutes to hours. This is called airborne transmission, and it can occur in enclosed spaces with poor ventilation. However, it is more common for COVID-19 to spread through close contact.

Less often, the illness can spread if you touch a surface with the virus on it, and then touch your eyes, nose, mouth, or face. But this is not thought to be the main way the virus spreads.

COVID-19 is spreading from person to person quickly. The United States Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) consider COVID-19 a serious public health threat globally and in the United States. The situation is evolving quickly, so it's important to follow current local guidance on how to protect yourself and others from getting and spreading COVID-19.

Symptoms

COVID-19 symptoms range from mild to severe. Older people and people with certain existing health conditions have a higher risk of developing severe illness and death. Health conditions that increase this risk include:

Symptoms of COVID-19 may include:

 (Note: This is not a complete list of possible symptoms. More may be added as health experts learn more about the disease.)

Some people may have no symptoms at all or may have some, but not all of the symptoms.

Symptoms may appear within 2 to 14 days after being exposed. Most often, symptoms appear around 5 days after exposure. However, you can spread the virus even when you do not have symptoms.

More severe symptoms that require seeking medical help right away include:

Exams and Tests

If you have symptoms of COVID-19, your health care provider may decide to test you for the disease.

If you get tested for COVID-19, swabs from the back of the nose, the front of the nose, or throat will be collected. If a person is thought to have COVID-19, these samples will be tested for SARS-CoV-2.

Treatment

If you are recovering at home, supportive care is given to help relieve symptoms. People with severe illness will be treated in the hospital. Some people are being given experimental medicines.

If you are being cared for in the hospital and are receiving oxygen therapy, treatment for COVID-19 may include the following medicines, which are still being evaluated:

If you test positive for COVID-19 and are at high risk for serious illness from the disease, your provider may recommend medicines called monoclonal antibodies.

Bamlanivimab or casirivimab plus imdevimab are two such regimens that have been approved for emergency use by the FDA. If given soon after you become infected, these medicines may help your immune system fight off the virus. They may be given to people with mild to moderate illness who are not hospitalized. 

Other possible treatments, such as plasma from people who had COVID-19 and have recovered, are being studied, but there is not enough evidence to recommend them at this time.

Based on available evidence, current treatment guidelines from the National Institutes of Health recommend against using some drugs for COVID-19, including chloroquine and hydroxychloroquine. Do not take any drugs to treat COVID-19 except those prescribed by your provider. Check with your provider before treating yourself or a loved one with vitamins, nutrients, or any medicines prescribed in the past for other health problems.

Possible Complications

Complications can include:

When to Contact a Medical Professional

You should contact your provider:

Call 911 or the local emergency number if you have:

Before you go to a doctor's office or hospital emergency department (ED), call ahead and tell them that you have or think you may have COVID-19. Tell them about any underlying conditions you might have, such as heart disease, diabetes, or lung disease. Wear a cloth face mask with at least 2 layers when you visit the office or ED, unless it makes it too hard to breathe. This will help protect other people you come in contact with.

Prevention

COVID-19 vaccines are used to boost the body's immune system and protect against COVID-19. These vaccines are a vital tool to help stop the COVID-19 pandemic.

Currently there are limited supplies of the COVID-19 vaccine. Because of this, the CDC has made recommendations to state and local governments about who should get vaccines first. Check with your local public health department for information in your state.

Even after you receive both doses of the vaccine, you will still need to continue to wear a mask, stay at least 6 feet away from others, and wash your hands often.

Experts are still learning about how COVID-19 vaccines provide protection, so we need to continue to do all that we can to stop the spread. For example, it is not known if a person who is vaccinated could still spread the virus, even though they are protected from it.

For this reason, until more is known, using both vaccines and steps to protect others are the best way to stay safe and healthy.

If you have COVID-19 or have symptoms of it, you must isolate yourself at home and avoid contact with other people, both inside and outside your home, to avoid spreading the illness. This is called home isolation or self-quarantine. You should do this immediately and not wait for any COVID-19 testing.

You should remain at home, avoid contact with people, and follow the guidance of your provider and local health department about when to stop home isolation.

It's also important to help prevent the spread of the disease to protect people at high risk of serious illness and to protect providers who are at the front lines of dealing with COVID-19.

For that reason, everyone should practice physical distancing. This means:

To find out what it happening in your community, check your local or state government website.

Learn more about COVID-19 and you:

For the latest research information:

Information about COVID-19 from the World Health Organization:

Related Information

Coronavirus

References

Centers for Disease Control and Prevention website. COVID-19: How to protect yourself & others. www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/prevention.html. Updated February 4, 2021. Accessed February 6, 2021.

Centers for Disease Control and Prevention website. COVID-19: Healthcare workers: Information on COVID-19. www.cdc.gov/coronavirus/2019-nCoV/hcp/index.html. Updated February 11, 2020. Accessed February 11, 2021.

Centers for Disease Control and Prevention website. COVID-19: Public health guidance for community-related exposure. www.cdc.gov/coronavirus/2019-ncov/php/public-health-recommendations.html. Updated December 3, 2020. Accessed February 6, 2021.

Centers for Disease Control and Prevention website. COVID-19: Frequently asked questions about COVID-19 vaccination. www.cdc.gov/coronavirus/2019-ncov/vaccines/faq.html. Updated January 25, 2021. Accessed February 6, 2021.

Centers for Disease Control and Prevention website. COVID-19: Treatments your healthcare provider might recommend if you are sick. www.cdc.gov/coronavirus/2019-ncov/your-health/treatments-for-severe-illness.html. Updated December 8, 2020. Accessed February 6, 2021.

Centers for Disease Control and Prevention website. COVID-19: What to do if you are sick. www.cdc.gov/coronavirus/2019-ncov/if-you-are-sick/steps-when-sick.html. Updated December 31. Accessed February 6, 2021.

National Institutes of Health. COVID-19 treatment guidelines. Therapeutic management of patients with COVID-19. www.covid19treatmentguidelines.nih.gov/therapeutic-management/. Updated February 11, 2021. Accessed February 11, 2021.

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Review Date: 2/7/2021  

Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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