Coronavirus: How long will the Bay Area have to stay home?

CLICK HERE if you’re having a problem viewing the photos on a mobile device.

When Gov. Newsom announced that Californians across the state would join the Bay Area in an unprecedented statewide order to stay home to curb the deadly spread of the coronavirus, he failed to answer one of the most pressing questions on the minds of 40 million residents suddenly held hostage in their own homes: How long will this last?

Nobody knows yet — but it will probably be a while.

“I would simply guess that a couple of months of lock-down would be required to flatten the curve in California to a level that, if we are lucky, we will be able to cope with the … cases,” said Dr. Nicholas A. Christakis, professor of Social and Natural Science at Yale University. “It’s very, very difficult to be sure.”

Newsom’s office will only say the order is “until further notice” and would not explain what the criteria might be for easing the restrictions, which came days after officials from seven counties in the Bay Area took the extraordinary step to lock down the region.

The idea is to “flatten the curve” of rising infections and fatalities to a level that doesn’t overwhelm hospitals and allows time to develop new treatments and eventually a vaccine. With alarming projections that more than 20 million Californians could catch the virus if nothing is done, the stay-at-home approach is one that health experts embrace and, if anything, say should have come sooner.

“What we do know is this is the best strategy short term,” said Dr. Arnold S. Monto, professor of epidemiology at the University of Michigan. “There’s universal acceptance of that.”

Monto and other public health experts said there are a lot of factors that would play into decisions on easing the restrictions and that many assumptions are based on past experiences with other viruses or situations in other countries that aren’t quite the same as in the U.S.

The statewide stay-at-home order, announced Thursday, for all but essential workers and necessities followed progressively tighter local and state restrictions on public gatherings and aims to maximize “social distancing” to keep people away from one another and reduce spread of the virus.

Such measures were used more than a century ago in the 1918 Spanish Flu pandemic and have been employed against the new coronavirus with some apparent success in China, where the COVID-19 outbreak originated in December.

In late January, as cases spiked in China, the country’s communist government put Hubei province and Wuhan, the city at the center of the outbreak, on full lock-down, shutting down travel, manufacturing and other industries and confining most residents to their homes. In rural areas, drones fly over the countryside reminding residents of the mandate to wear face masks.

Seven weeks later, the Chinese government now has begun easing restrictions as new infections subside, allowing manufacturers, food processors and other Wuhan businesses seen as critical to the economy to reopen, according to the Associated Press.

That could offer a clue to what’s in store for Californians and other Americans — New York, Connecticut and New Jersey announced similar statewide restrictions on non-essential workers Friday.

But much remains uncertain about the results in China and what they might mean for Americans, said Catherine Troisi, an infectious disease epidemiologist at The University of Texas Health Science Center at Houston. China’s Hubei quarantine was far more restrictive than California’s stay-home order.

“Basically everything was shut down,” Troisi said. “That would never fly in the U.S.”

What’s more, China only recently began easing up on its quarantine, and due to the lag time between becoming infected and falling ill, it remains to be seen whether cases begin spreading in Wuhan again.

“What happens when these draconian quarantine rules are eased up? Will we start to see community spread again?” Troisi asked.

Social distancing also was employed against the 1918 influenza pandemic to varying degrees around the country, Troisi said. But the various quarantines, church closures, mask ordinances, bans on door-to-door sales, sequestration of children and other measures weren’t employed all at once or consistently from city to city, making it difficult to draw conclusions of how long they need to be in place to work.

“Different cities did different amounts of these,” Troisi said of the Spanish flu epidemic. “They didn’t just do everything Day One and stop eight weeks later.”

The 1918 flu cases began spiking in the fall, and Christakis said distancing measures such as school closures and public-gathering bans in the city of St. Louis lasted 153 days. Infections tapered off in the summer — which Troisi attributes mostly to schools being out than to warmer weather, noting that kids’ “hygiene isn’t the best.”

“They’re not good about covering their cough, washing their hands,” Troisi said. “When they’re not in groups every day, transmission may slow down.”

Christakis said the new coronavirus pandemic seems most like the 1957 influenza pandemic, which killed 110,000 Americans. But people already were social distancing due to polio, so it isn’t clear how long that quarantine lasted and is hard to draw comparisons.

And every virus is different. Influenza infections tend to subside in the summer and return in the fall. With the Sudden Acute Respiratory Syndrome outbreak of 2003, caused by a deadlier but less infectious cousin of the new coronavirus, it was easier to contain because it didn’t spread through people who didn’t feel sick, as coronavirus does. The SARS virus wasn’t contagious until the infected felt sick and symptoms were so severe the sick tended to stay home, limiting its spread, Troisi said.

“There is no way to tell,” Monto said. “There are these projections based on assumptions put into models based on influenza that this will calm down over the summer and come back in the fall. We have no way of judging. We all predicted SARS would not go away, and it did. Based on that observation, we can only speculate what will happen long-term here.”

Because the new coronavirus transmits more easily than influenza or SARS through people who are infected but not yet feeling sick, it may take a longer lock-down to contain its spread.

“The more infectious it is,” Troisi said, “the more social distancing has to be in place.”

Experts say it’s unlikely the new restrictions in California will end at once. More likely, there would be a sort of reversal of the gradual ramp up in recent weeks from a few cities and counties banning large gatherings of 1,000 or more, then lowering the number to 250 and finally the Bay Area and then the state ordering residents to stay home entirely except for essential work or needs.

Determining when to ease the new stay-home restrictions will involve a balancing act for public officials weighing the cost to the economy and student education of a prolonged lock-down against its success in reducing new infections and fatalities. Related Articles Emmy Awards 2020: 2 Oakland actors stun with huge wins

Biden to focus on health care in Supreme Court debate

Hundreds of Catholics gather in San Francisco to decry COVID-19 limits on worship

Coronavirus cases, deaths continue to decline as flu season begins

Coronavirus glossary: Terms that became part of our daily dialogue in the past 6 months

“It all depends on the public’s tolerance for death,” Christakis said. If parts of the U.S. look like northern Italy, where hospitals are overrun and doctors are triaging patients, Californians might be fine with a longer home confinement. But at some point, as cases ease, they will tire of it.

“At a minimum I’d say we’ll be doing this for three weeks,” Christakis said, “but we’ll be doing some form of this for months.”

Share this: Print

View more on The Mercury News