Updated at 2:30 p.m. ET on March 7
Since Jan. 21, health officials have identified hundreds of cases of COVID-19 in the United States and 17 deaths. The respiratory disease caused by a novel coronavirus has spread to dozens of countries and has killed thousands since it was first reported in Wuhan, China, in December.
The cases reported by the U.S. Centers for Disease Control and Prevention include people who flew back to the U.S. on flights chartered by the U.S. State Department, such as those who were aboard the Diamond Princess cruise ship.
Washington State and California have seen especially large case numbers.
The virus is thought to spread mostly through close contact and is more dangerous for people who have underlying health conditions, the CDC says. So far, the virus has proved more dangerous for the elderly. The CDC recommends basic precautions such as hand-washing to avoid spreading the disease, and it discourages travel to several countries with outbreaks of COVID-19, including China, Iran, Italy and South Korea.