San Francisco is doing it. France, Spain and Italy, too.

They have locked down their residents to fight the exponential spread of the new coronavirus.

Oregon is taking some tough but incremental steps – Gov. Kate Brown just extended K-12 school closures through April 28 and banning dining inside restaurants – but hasn’t embraced more extreme measures.

The logical question now on many people’s minds: Has the time come for a societal lockdown? What does it look like? And how long would it last?

San Francisco and some neighboring communities on Tuesday became the first large metro area in the nation to take such drastic measures after California leaders issued a shelter-in-place order.

It mandates that about 7 million residents stay home except to get food, seek necessary medical care or go to “essential” jobs for at least the next three weeks.

France also has joined Spain and Italy in sequestering its residents -- with French President Emmanuel Macron saying he was instituting the 30-day measure because: “We are at war. The enemy is invisible and it requires our general mobilization.”

Oregon has identified 68 cases of the new coronavirus in 14 counties and two people have died. Two have died just across the river in Clark County. Limited testing in both states means the number of COVID-19 cases is drastically undercounted.

Nationwide, more than 5,500 have been diagnosed, with more than 100 deaths, according to The New York Times’ tracker. The number of confirmed cases has more than quadrupled in a week’s time in the U.S. -- in part because more testing has become available but has not come anywhere close to demand.

Oregon doctors have written to Gov. Kate Brown and Vice President Mike Pence laying out an aggressive coast-to-coast response that includes closing schools “proactively” and instituting social isolation measures immediately.

That means no one should leave their homes in affected regions “except for medical care, essential supplies, essential work services and compelling other reasons” that are clearly defined, the letters read.

More than 430 doctors have signed the state letter and nearly 5,000 medical professionals have signed the letter to Pence, leader of the U.S response.

They say they’re bracing for a massive wave of people requiring hospitalization because of COVID-19. They also want to keep people with mild cases or those not showing symptoms from infecting others without knowing it.

“We see ourselves making decisions in the next weeks and months on who will live, and who will die because we don’t have resources sufficient to care for them,” read the letter to Pence, which similar to the one to Brown.

“We have heard the stories second- and farther-hand from China and Italy and have no reason to think the United States won’t suffer the same fate,” the letter continues. “We must flatten the curve of this pandemic to save lives.”

***

A study published Monday by the American Association for the Advancement of Science found that asymptomatic people or people whose symptoms were so mild they didn’t realize they were infected were a major driver of the disease from its epicenter in Wuhan, China, to the rest of the world.

The study found that this group of roving people -- whose infections were never diagnosed -- were responsible for spreading the disease to 79 percent of the people who were diagnosed in China.

The study concluded that this massive category of people will make containing COVID-19 “particularly challenging” and will require governments to radically increase testing and isolation of these people.

Some politicians and celebrities in recent days have announced their diagnoses – which were made even before they felt any symptoms.

Miami Mayor Francis Suarez said he was tested last Thursday and he received a positive test result Friday, the same day he started feeling a slightly scratchy throat, like a cold was coming on. Two days after that, he said he had only “mild to almost no symptoms right now, so I’m very fortunate that I seem to be for the moment in that 80 percent category that’s experiencing mild to no symptoms.”

In my fifth digital journal, I explain how my condition directly ties into the importance of social distancing, as well as another bold action the @CityofMiami is now taking to promote that. #InThisTogether pic.twitter.com/oM3dB4wK47 — Mayor Francis Suarez (@FrancisSuarez) March 17, 2020

Suarez said his case could bolster the case for social distancing. He said he wouldn’t have known he had the disease unless he got tested after twice being in the same rooms as Fabio Wajngarten, the press secretary to Brazilian President Jair Bolsonaro, earlier this month.

On Monday, English actor Idris Elba -- known to Americans for playing Russell “Stringer” Bell on “The Wire” and the lead in the English detective show “Luther” -- tweeted out a video announcing he’d been diagnosed with COVID-19, even though he feels normal.

This morning I tested positive for Covid 19. I feel ok, I have no symptoms so far but have been isolated since I found out about my possible exposure to the virus. Stay home people and be pragmatic. I will keep you updated on how I’m doing 👊🏾👊🏾 No panic. pic.twitter.com/Lg7HVMZglZ — Idris Elba (@idriselba) March 16, 2020

“Look, this is serious, you know,” Elba said in a video viewed more than 30 million times. “Now’s the time to really think about social distancing, washing your hands. Beyond that, there are people out there who aren’t showing symptoms and that can easily spread it.”

He emphasized: “Stay home people and be pragmatic.”

***

Oregon’s governor as recently as last Wednesday morning had instituted no social distancing measures of significance and said she would keep schools open.

But Brown has taken more dramatic steps in the days that followed.

She first banned public gatherings of more than 250 people, then closed all schools until April 1. Then this past Monday she banned gatherings of 25 people or more, but advised Oregonians to avoid groups of 10 or more people. She also said she was shuttering restaurants, with the exception of takeout and food delivery for at least four weeks, followed by Tuesday’s extension of the schools closing.

The governor has acknowledged that the increasingly stringent measures have enormous financial impacts on businesses and people who need their jobs to support themselves and their families.

She and Oregon’s public health officials also have said shutting schools is detrimental to the learning process and disproportionately affects low-income students and their parents, who rely on the schools for free or reduced-price meals for children and childcare.

Dr. Maxine Dexter, a pulmonary and critical care physician for Kaiser Permanente in Clackamas, said she thinks the governor’s recent steps are moving in the right direction.

But they aren’t enough, said Dexter, who co-wrote the letters to Brown and Pence.

Dexter believes the governor should issue a stay-at-home directive that allows people to leave home only for groceries, gasoline, medical needs or essential service jobs (such as medical staff, people who work in the grocery industry, garbage collectors and workers who run utilities that provide heat, water and electricity).

Restaurants should be completely closed and schools should remain closed, too, she said.

Dexter is running for state House District 33, which covers parts of Multnomah and Washington counties, but said she has suspended her involvement in her campaign to focus on her medical work as the coronavirus continues.

Elsewhere in Oregon, medical providers are nervous about the onslaught they expect in coming weeks.

Along the Oregon coast, some medical staff are bracing for spring break vacationers to arrive, expecting an influx of people who are relieved to get respite from being cooped up at home with their kids for the past week.

One nurse, who asked not to be identified because of the backlash she’s already received from businesses in Tillamook County, said she’s asking people from other parts of the state to cancel their vacation plans.

“Please stay home,” she said, noting that Oregon coastal towns don’t have enough hospital beds for area residents, let alone out-of-towners who might become feverish and develop a dry cough while in town. Those are the top two symptoms of the disease.

The nurse also worries about people from one part of the state spreading the virus to new parts of the state through travel and further depleting dwindling supplies of groceries.

***

Bay Area engineer Tomas Pueyo analyzed the growth curves of coronavirus in China, the U.S. and other countries around the world in a piece -- “Coronavirus: Why You Must Act Now” – that has been translated into 28 languages and viewed more than 35 million times.

One of Pueyo’s main findings is that an all-out lockdown in China -- which literally meant locking some residents in their apartment complexes and barricading neighborhoods -- worked to stem the spread of the disease.

"Every day that there isn’t social distancing, these cases grow exponentially." These graphs will help you understand what's happening as #COVID19 spreads.



✍️ On Medium: Coronavirus: Why You Must Act Now, by Tomas Pueyo https://t.co/tW6muc8pzU — Medium (@Medium) March 12, 2020

On Tuesday, the Chinese government reported just 21 new cases -- 20 of them imported from people traveling into the country. At the peak of the epidemic, the country was logging more than 3,000 new cases per day. (It remains to be seen if the government can contain the disease when roughly half of the 1.4 billion people whose movements were restricted return to work.)

Pueyo also looked at why the number of new cases has exploded exponentially in, for example, Italy and Iran.

That’s striking when cases haven’t in Taiwan, Singapore, Japan and Hong Kong, which all have much closer ties to mainland China. Pueyo and many experts say that’s because those nations were hit hard by another coronavirus -- SARS -- in 2003 and they developed aggressive pandemic plans that they swiftly put into motion.

As of Tuesday, Taiwan, with 23 million residents, had just 77 cases.

“They very quickly limit people coming in, identify the sick, immediately isolate them, use heavy protective gear to protect their health workers, track all their contacts, quarantine them,” Pueyo said of the successful governments.

It’s too late for other countries such as the U.S. to enact similar measures to limit the spread because too much time has been squandered by gradually instituting social distancing measures like limiting large public gatherings that do decrease the spread of disease, he said. But what’s needed at this point, he argued:

“If you want to be safe, do it Wuhan style,” he said. “People might complain now, but they’ll thank you later.”

***

Chunhuei Chi, the director of the Center for Global Health at Oregon State University, believes the state and the rest of the country don’t need a dramatic lockdown yet. But that means a serious investment in public health.

In order to do that, government must closely track each person who has had contact with a known case, Chi said.

He has studied many nations’ responses to the novel coronavirus and agrees that Taiwan’s is the most effective.

In Taiwan, Chi said, every asymptomatic person with close contact to a confirmed case is ordered into home quarantine for 14 days, tracked through GPS on their cellphones and tested both at the beginning and end of the two weeks.

Compared to Oregon, Taiwan also appears to define “close contacts” widely -- quarantining not only family members of a confirmed case but also colleagues and students if, for example, their teacher has been diagnosed.

Officials from the Oregon Health Authority told The Oregonian/OregonLive earlier this month that they were asking some – but not all -- asymptomatic people who’d had close contact with diagnosed people to self-quarantine at home, under the honors system. Officials had been monitoring their status.

Oregon Health Authority officials also said they weren’t testing people in this group unless they developed symptoms. But Thursday, a spokesman said the agency is stretched so thin that it would no longer monitor this group at all.

Chi said if people who have been ordered to quarantine in Taiwan go out in the community against orders, they’re fined.

Chi also said Taiwan has sent out clear public health messages that has educated the population. For example, people are advised to change their “outside” clothes and wash them when they get home, replacing them with “indoor” clothes, Chi said. Of course, it’s a tradition not to wear shoes inside, too.

“From the beginning, Taiwan treated this as a war, like we are fighting for their survival,” Chi said. “We have to take this threat far more seriously. If we think we are fighting for our survival, then the state should spare not resources, put everything into it.”

-- Aimee Green; agreen@oregonian.com; @o_aimee

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