What Is COVID-19?
COVID-19, short for coronavirus disease 2019, is a respiratory disease caused by a novel coronavirus named SARS-CoV-2. It can cause mild to severe illness and can lead to hospitalization or death. Since the onset of COVID-19 in the United States, over six million people have been hospitalized and over one million have died from COVID-19. COVID-19 causes common respiratory symptoms that can be confused with a cold or the flu, however, COVID-19 can also affect other parts of your body. Some people will also develop Long COVID which are long-term effects from a COVID-19 illness.
How COVID-19 Spreads
COVID-19 most commonly spreads through the air when a person with COVID-19 breathes out small particles and respiratory droplets and other people around them breathe them in. Respiratory droplets can also get on surfaces and be spread through touch. COVID-19 can be spread even when a person does not have symptoms.
COVID-19 Variants
Like most viruses, the virus that causes COVID-19 changes constantly. These changes can result in new strains or variants of the virus. Along the way, scientists name the new variants which is why you may have heard names like Delta, Omicron, and many others. Some changes to the virus strains allow the virus to spread more easily or make it resistant to treatments (like antivirals) or available vaccines. New variants will continue to occur and there are agencies that monitor emerging variants. We have the tools to help protect ourselves and our communities against COVID-19.
People at Higher Risk for Severe Illness
Anyone can have mild to severe symptoms from COVID-19. There are some individuals who are at higher risk for severe illness from COVID-19, meaning they may end up needing to be hospitalized, put in the intensive care unit, need a ventilator to help them breathe or they may even die.
This includes:
- Adults over age 50 are at higher risk. Risk increases as you age so the older you are, the higher your risk with the greatest threat being to individuals over the age of 85 years old.
- People of all ages with underlying medical conditions, particularly if not well controlled, including:
- People with chronic lung diseases including:
- Chronic obstructive pulmonary disease (COPD), including emphysema and chronic bronchitis
- Asthma that is moderate to severe
- Bronchiectasis
- Having damaged or scarred lung tissue such as interstitial lung disease, including idiopathic pulmonary fibrosis
- Cystic fibrosis
- Pulmonary hypertension
- Tuberculosis
- People who are immunocompromised or have a weakened immune system.
- People living with a current cancer diagnosis, including lung cancer. Having a history of cancer may increase your risk as well.
- People who are a current or former smoker
- People who are overweight (body mass index [BMI] of 25 or higher), with obesity (body mass index [BMI] of 30 or higher) and especially severe obesity (BMI of 40 or higher). The higher the BMI, the higher the risk of severe illness from COVID-19.
- People with chronic lung diseases including:
- Other medical conditions including serious heart conditions, type 1 or 2 diabetes, people with some types of disabilities, neurological conditions such as dementia, mood disorders such as depression or schizophrenia, HIV infection, chronic liver disease, have cerebrovascular disease, substance use disorders (including alcohol, opioids or cocaine use) and people with chronic kidney disease.
- People who are pregnant or recently pregnant
Children have been less affected by severe illness from COVID-19 than adults, though they can also experience severe symptoms up to and including death. Children with underlying medical conditions are at increased risk for severe illness. Learn more about COVID-19 and kids.
Reviewed and approved by the American Lung Association Scientific and Medical Editorial Review Panel.
Page last updated: October 30, 2024
