Frequently Asked Questions about COVID-19

COVID-19 is a contagious disease caused by the SARS-CoV-2 virus.

COVID-19 most often causes respiratory symptoms similar to a cold, influenza (flu), or pneumonia but can also affect other parts of your body. Most people with COVID-19 have mild symptoms, but some people become severely ill.

More than 1 million people have died from COVID-19 in the US since the virus first emerged in Wuhan, China in December 2019. Cases have been detected in most countries worldwide, and on March 11, 2020, the World Health Organization characterized the outbreak as a pandemic. Human-to-human transmission occurs through close contact.

Coronavirus disease digital illustration






COVID-19 Variants

Updated March 2024

Sources: American Academy of Pediatrics, Centers for Disease Control and Prevention, Food and Drug Administration

Learn more about coronaviruses at

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