One of the Americans evacuated from Wuhan, China, amid the coronavirus outbreak has been placed under quarantine after trying to leave March Air Reserve Base, where a chartered flight landed the previous day, Riverside County health officials said Thursday.
The approximately 200 American passengers on the plane were asked to remain at the military base so they could be monitored for symptoms of the virus, but the person tried to leave, prompting the quarantine order from Riverside County Public Health Officer Dr. Cameron Kaiser, officials said.
As a result, the traveler will be required to "stay for the entire incubation period or until otherwise cleared," according to a statement from the agency. The incubation period is two weeks.
The action was taken as a precautionary measure due to the unknown risk of someone leaving the Riverside County base without undergoing a full health evaluation, the statement read.
All of the passengers from the flight that arrived Wednesday are expected to be monitored at the base for at least three days for signs of the virus.
None of the passengers showed signs of the illness after being evacuated from the epicenter of the deadly coronavirus outbreak. However, they agreed to stay voluntarily, according to Dr. Chris Braden of the U.S. Centers for Disease Control and Prevention.
U.S. health officials were not expected to issue a blanket quarantine for the evacuees.
Meanwhile, Rep. Norma Torres, a Democrat who represents California's 35th District, on Thursday requested an investigation into the federal planning, coordination and communication for the chartered flight, which was initially scheduled to land at Ontario International Airport before the flight was ultimately diverted.
"For two days, the Department of State and the Department of Health and Human Services left Inland Empire residents alarmed about the risks posed by potential coronavirus patients being flown into a public space at the heart of our community, and confused by the utter lack of a coherent plan to keep anyone safe,” Torres said in a statement. “ONT was up to this task immediately, but that does not excuse the dismal lack of communication by the federal government."
Also on Thursday, the World Health Organization declared a global emergency over the Novel coronavirus, which has killed at least 170 people and infected nearly 8,000 others in China, most of them in the hardest-hit city of Wuhan.
There are nearly 100 confirmed cases outside of mainland China. The first person-to-person spread was reported in the U.S. Thursday after a Chicago woman infected her husband, bringing to the total cases in this country to six.
Two of the cases are in Southern California, one each in L.A. and Orange counties.
Anyone with questions about coronavirus can contact Riverside University Health System Public System information line at 951-358-5134 or visit the agency's website.
CNN contributed to this story.