COVID-19 is a disease caused by a virus called SARS-CoV-2. Most people with COVID-19 have mild symptoms, but some people can become severely ill. Although most people with COVID-19 get better within weeks of illness, some people experience post-COVID conditions. Post-COVID conditions are a wide range of new, returning, or ongoing health problems people can experience more than four weeks after first being infected with the virus that causes COVID-19. Older people and those who have certain underlying medical conditions are more likely to get severely ill from COVID-19. Vaccines against COVID-19 are safe and effective.

COVID-19 spreads when an infected person breathes out droplets and very small particles that contain the virus. These droplets and particles can be breathed in by other people or land on their eyes, noses, or mouth. In some circumstances, they may contaminate surfaces they touch. People who are closer than 6 feet from the infected person are most likely to get infected.

COVID-19 is spread in three main ways:

• Breathing in air when close to an infected person who is exhaling small droplets and particles that contain the virus.
• Having these small droplets and particles that contain virus land on the eyes, nose, or mouth, especially through splashes and sprays like a cough or sneeze.
• Touching eyes, nose, or mouth with hands that have the virus on them.

For more information about how COVID-19 spreads, visit the How COVID-19 Spreads page to learn how COVID-19 spreads and how to protect yourself. 

Visit the How to Protect Yourself & Others page to learn about how to protect yourself from respiratory illnesses, like COVID-19.

People who have been in close contact with someone who has COVID-19—excluding people who have had COVID-19 within the past 3 months or who are fully vaccinated

• People who have tested positive for COVID-19 within the past 3 months and recovered do not have to quarantine or get tested again as long as they do not develop new symptoms.
• People who develop symptoms again within 3 months of their first bout of COVID-19 may need to be tested again if there is no other cause identified for their symptoms.
• People who have been in close contact with someone who has COVID-19 are not required to quarantine if they have been fully vaccinated against the disease and show no symptoms.

For more information, see COVID-19: When to Quarantine and What to Do If You Are Sick.

People with COVID-19 have reported a wide range of symptoms – from mild symptoms to severe illness. Symptoms may appear 2-14 days after exposure to the virus. If you have fever, cough, or other symptoms, you might have COVID-19.

Look for emergency warning signs* for COVID-19. If someone is showing any of these signs, seek emergency medical care immediately

• Trouble breathing
• Persistent pain or pressure in the chest
• New confusion
• Inability to wake or stay awake
• Pale, gray, or blue-colored skin, lips, or nail beds, depending on skin tone

*This list is not all possible symptoms. Please call your medical provider for any other symptoms that are severe or concerning to you.