EUREKA (CBS SF) -- Humboldt County health officials have announced that they were treating their first confirmed case of coronavirus and a second person was being tested for the illness.
Meanwhile, Sacramento County Public Health officials also announced their first confirmed case. Officials said the individual returned from China to the United States on Feb. 2 and has since self-quarantined and taken precautionary measures upon their return home. The individual began displaying mild symptoms during the self-quarantine.
"Currently, the individual is asymptomatic, but will remain home for mandatory isolation until cleared by Sacramento County Public Health," the office said in a press release. "Sacramento County Public Health's investigation determined that currently, the public's risk of exposure is extremely low."
COMPLETE COVERAGE Coronavirus Outbreak -- California and Beyond
In a Friday teleconference, officials from the Centers for Disease Control and Prevention said the Humboldt County case raised the number of confirmed coronavirus cases of residents within the United States to 13.
Another 18 cases have been reported among the Diamond Princess passengers who were airlifted to the United States and three others from commercial flights to the U.S. from Wuhan, China.
The patient count reflected a change the agency put in place on Friday as to how it will be reporting cases. Now cases will be reported as either U.S. cases -- those contracted within the United States -- and repatriated cases -- those who contracted the illness while being outside the country.
The CDC also gave a breakdown on where the infected Diamond Princess passengers were being treated. Five are in Northern California hospitals, including one in San Francisco, 11 were being treated at the University of Nebraska medical center and two were in hospitals near Lackland Air Base in Texas.
Federal officials, however, warned that those quarantined passengers from Diamond Princess were at high risk for infection -- "We expect to see additional cases."
Dr. Roberta Luskin-Hawk, chief executive of St. Joseph Health, told the Eureka Times Standard that two patients had been evaluated for coronavirus at the hospital in Eureka on Sunday.
"After a thorough investigation, at this time, we have no evidence that any patients were exposed during the visit," Luskin-Hawk said in the statement to the paper. "There was no close or prolonged contact with anyone in the Emergency Department. We followed established protocols from the moment the patients arrived. They were admitted straight to a special isolation room that has negative pressure to minimize the risk of exposure."
The patients were an unidentified individual and a "close contact."
County health officials said the pair were "doing well and self-isolating at home, while being monitored for symptoms by the Public Health Communicable Disease Surveillance and Control Unit."
Around the world the crisis with the disease continued to grow.
In South Korea, schools were shuttered, churches told worshipers to stay away and some mass gatherings were banned as cases of a new virus swelled. The country said two people have died and 204 have been infected with the virus, quadruple the number of cases it had two days earlier, as a crisis centered in China has begun strongly reverberating elsewhere.
The multiplying caseload in South Korea showed the ease with which the illness can spread. Though initial infections were linked to China, new ones have not involved international travel.
The World Health Organization warned that such clusters not directly linked to travel from China suggest that time may be running out to contain the outbreak.
"The window of opportunity is still there. But our window of opportunity is narrowing," said WHO Director-General Tedros Adhanom Ghebreyesus. "We need to act quickly before it closes completely."
Globally, more than 76,000 people have been infected in 27 countries, and more than 2,200 have died. Even as new alarms were sounded elsewhere in Asia, in China, where the vast majority of cases have occurred, officials have expressed optimism over the number of new infections, which has been trending downward. China said Friday 889 new cases were recorded in the preceding 24 hours and 118 additional deaths.
Italian authorities say the number of people infected has more than quadrupled due to an emerging cluster of cases in the country's north. Many of the new cases represented the first infections in Italy acquired through secondary contagion and brought the country's total to 14 on Friday. The first to fall ill in northern Italy met with someone who had returned from China on Jan. 21 without presenting any symptoms of the new virus, health authorities said.
The U.S. Department of State is advising citizens to reconsider cruises to or in East Asia and the Asia-Pacific Region.
© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.
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