There are no confirmed cases of the virus in San Francisco, she assured the community during her press conference, so she explained the reason for the emergency declaration.
"By declaring a state of emergency we are prioritizing the safety of our communities by being prepared," Mayor Breed said. "Our number one goal is the health and safety of all our residents."
She says not only does the declaration kickstart the mobilizing of city resources, streamlining staff, and coordinating agencies across the city, but it allows for future reimbursements from the state and federal governments.
WATCH: Full press conference from London Breed, SF city officials
The Director of the Department of Health, Doctor Grant Colfax, agrees with the precaution.
Dr. Colfax also spoke at the press conference, saying in part, "Given the high volume of travel between San Francisco and mainland China and the spread of the virus to other countries, there is a growing likelihood that we will see cases in San Francisco."
He told the crowd the health department is "already working with the community and elected officials to "mitigate the harm of the new virus if it emerges in San Francisco."
"We are looking at a global outbreak that has entered a new phase," Dr. Colfax said.
Both Breed and Dr. Colfax discussed the impact of the deadly virus on San Francisco's Chinese community.
Many are living with fear for the health of their families overseas, and now, Dr. Colfax says, a new form of discrimination.
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They are experiencing "a stigma and discrimination," he said. "This virus is not about race, ethnicity or culture. The risk of getting coronavirus is based on travel history and contact with people who are sick."
Mayor Breed encouraged the public to keep visiting Chinatown.
"We should continue to support the neighborhoods we love, like Chinatown," she said. "It's an amazing neighborhood and we will continue to be very supportive."
San Francisco supervisor, Hillary Ronen, is supportive of the Mayor's declaration and described it as a positive step toward prevention.
"There is pretty much planning happening non-stop right now. The Department of Public Health is having a daily phone call with the region, with the state, with the feds," said Supervisor Ronen, who added. "We're asking the public not to panic, but to prepare, just like we are doing in the city and county of San Francisco."
Many San Francisco families are concerned about what active coronavirus could mean for their children.
SFUSD spokeswoman, Gentle Blythe, says school closures are possible and could happen very quickly. "Our first priority will be our student's safety."
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"If there's a confirmed case the Department of Public Health would immediately notify us, and we would enact a plan."
City Hall, public health officials, and SFUSD all urge people to stay home from work or school, if you are sick.
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