Six counties across the Bay Area in California issued a “shelter in place” order on Monday for all residents – requiring roughly 6.7 million people to stay in their homes – in an attempt to slow the coronavirus outbreak.

For the next three weeks, people living in San Francisco, Santa Clara, San Mateo, Marin, Contra Costa and Alameda counties will be restricted from all “non-essential travel” by “foot, bicycle, scooter, automobile, or public transit” outside their homes. Also, most businesses will be forced to close until April 7, starting at midnight on Monday.

"Because of the risk of the rapid spread of the virus, and the need to protect all members of the community and the Bay Area region, especially including our members most vulnerable to the virus and also health care providers," the order states, "this Order requires all individuals anywhere in San Francisco to shelter in place – that is, stay at home – except for certain essential activities and work to provide essential business and government services or perform essential public infrastructure construction, including housing."

San Francisco Mayor London Breed, speaking at an online streaming news conference, encouraged residents to stay calm and thanked both officials and the public for remaining diligent during the unprecedented public health emergency. Emphasizing that the directive came directly from county health experts, she also encouraged everyone to continue washing their hands and cleaning surfaces and keeping distance from others when entering public.

"These measures will be disruptive to everyday life," she said, "but there is no need to panic." Breed also shared that the counties could amend the order, making it either shorter or longer, depending on what happens in the coming weeks.

People will be allowed out only to shop for food and health care supplies, to help family and friends, or leave the area if they are not residents. County health officials also said outside recreation, including dog-walking and hikes, are allowed.

Transportation options – including airports, taxis and public transit – will remain in operation but will be available only for “essential travel.” The order is vague on enforcement but does include a call for the police to ensure compliance to keep the public inside.

"We know in San Francisco we can’t do it alone," Breed said. "We have to do it together."

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The unprecedented move comes amid a spike in cases across California, despite efforts by state, local and federal officials to encourage social distancing and slow the spread of the outbreak. As of Monday afternoon, 511 cases were reported in California, with 277 in the Bay Area – a number considered much smaller than actual amount of people infected with the virus.

California Gov. Gavin Newsom on Sunday called for more isolation efforts across the state, especially for those 65 and older or who have chronic diseases, whom he ordered to stay home. He also called for all bars, wineries and brewpubs to close.

"We believe this is a non-essential function in our state," Newsom said of the nightlife establishments. In Los Angeles, Mayor Eric Garcetti followed with more stringent restrictions closing all bars and restaurants in the city for all dine-in services.

Cody Ginsberg, a bartender who works in the neighborhood, said he appreciated the order even if it means he won’t be able to go to work for the next three weeks or more.

“It’s sad,” he said, “but I would rather find out we did too much than we did too little in the end.”

His bar has been full in recent weeks, despite pleas from public officials for people to avoid crowded areas. Many of the patrons, he added, are seniors.

“At work I deal with a lot of older patrons and I wouldn’t want to see any of them get sick because of me,” he said, adding that the bar has been spraying everything with bleach water six times a day.

“My hands are starting to get dry and cracked with how often I am washing them.”

People are still encouraged to come in, and locals have gladly obliged.

“There have been some times that have been really busy,” he said. “From what I have been hearing around, from other local bars, no one is going downtown anymore and everyone is staying home so the neighborhood bars are being hit more.”

His bar will stay open until the order goes into effect at midnight, and they are expecting one “last hurrah” before closing.

Across the U.S., officials are racing to contain the spread of the virus, and tests continue to be in short supply. California had conducted 8,316 tests as of Sunday.

Breed concluded the news conference by acknowledging the significant economic hardship caused by the order and said the counties were working quickly to help vulnerable communities.

Emphasizing that grocery stores, gas stations, pharmacies, and other establishments that provide important everyday goods for people will remain open, she again asked people not to panic.

"There is no need to rush out to do things at these particular locations because they will be available to you," she said, and she later added that there will not be a ban on food delivery. She also heralded the leaders in the area, who she said were far ahead of the curve. "We know there is more to do," she said, "and there will be more to come."

This is a developing story. Please check back for updates.