COVID-19 basics

What is COVID-19?

COVID-19 refers to the human infection caused by the new coronavirus strain, SARS-CoV-2. There are several coronaviruses already known to infect humans and animals such as bats, camels, cats, and more. Human infections caused by coronaviruses usually result in a mild upper respiratory infection (such as the common cold). Prior to COVID-19, two other coronaviruses (SARS, MERS) were known to cause more serious lower respiratory infection (pneumonia). COVID-19 is a new virus strain that is believed to have originated around the city of Wuhan, China, and started spreading among people in late 2019.

When did the first case of COVID-19 occur in the United States?

The first U.S. case was announced Jan. 21, 2020, in Washington state.

What is the source of the outbreak?

We know that the closest coronavirus relatives of this current virus are all harbored in Asian bats. Investigations are ongoing to determine the virus' source.

Why is this virus so dangerous? 

COVID-19 is dangerous because it is new, so no humans have had any prior infections with it, therefore no one is immune to it. Although most cases are mild, given our global population, even a small percentage of significantly ill people results in a much higher burden of patients requiring hospital care. 

Is COVID-19 a pandemic?

Yes, there is broad global spread of COVID-19, consistent with a pandemic. 

Will the pandemic be stopped?

The COVID-19 infection has spread globally. Herd immunity is the only way to slow, or stop, the current transmission. We can achieve herd immunity in one of two ways: through illness (natural herd immunity) or through vaccination. Since illness leads to severe disease or death for many, getting vaccinated is a much better alternative.