The medical impact of the new coronavirus is coming into sharper focus as it continues its spread in what is now officially recognized as a pandemic.

Its true fatality rate isn't yet known, but it seems 10 times higher than the flu, the United States' top infectious disease expert told lawmakers last week.

Most people have had mild to moderate illness and recovered, but the virus is more serious for those who are older or have other health problems.

In the U.S., 60% of adults have at least one underlying health condition and 42% have two or more.