The Centers for Disease Control and Prevention (CDC) said Tuesday that the first U.S. case of the Wuhan coronavirus was identified in Washington state. A male patient carrying the mysterious respiratory virus is currently at a medical center in Everett, Washington.

The virus, which was first detected in the central Chinese city of Wuhan, has killed six people and sickened 300 others in China. The virus originated at a seafood and poultry market in the city, which has a population of about 11 million. The virus can be transmitted from animals to humans.

Cases have also been reported in other Asian countries, including Japan and Thailand.

The man infected with the virus in Washington had traveled to Wuhan. The CDC has said that the virus remains a low-level threat to the U.S.

Some of the virus’ symptoms include fever, cough and difficulty breathing. The virus is most deadly to the elderly or those with weaker immune systems.

"Information is rapidly evolving. We hope over the coming days the situation will become clear," Dr. Nancy Messonnier, director of the CDC’s National Center for Immunization and Respiratory Diseases said. She said that the Washington state patient who has the virus is “doing well.”

Last week, the CDC began monitoring passenger travel from Wuhan at three U.S. airports: New York John F. Kennedy International Airport, San Francisco International Airport and Los Angeles International Airport. On Tuesday, the CDC also said it would expand its screening operations to Atlanta’s Hartsfield-Jackson Airport and Chicago’s O’Hare.

The World Health Organization will meet Wednesday to decide whether to declare the outbreak an international emergency.