Coronavirus Today: This map shows real-time risk

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Good evening. I’m Amina Khan, and it’s Wednesday, Nov. 11. Here’s what’s happening with the coronavirus in California and beyond.

The temptation to see friends and family over the fast-approaching holiday season seems to grow with each passing day, and you’re probably wondering just how risky it would be to get together in person. (I know I am!) Unfortunately, this type of risk is not something humans are super-well-equipped for assessing on our own.

So here’s a little bit of news you can use: Scientists at Georgia Tech have developed a tool that shows you the COVID-19 risk anywhere in the country — and in real time.

For example, my colleague Deborah Netburn explains, you can use the interactive tool to assess the risk of encountering at least one person infected with the coronavirus at a bar in Denver (78%), a 100-person wedding in Baltimore (68%) and a Thanksgiving dinner with 25 guests in Los Angeles (25%).

The COVID-19 Risk Assessment Planning Tool is meant to help policy makers, event planners and regular folks easily grasp the potential dangers associated with having gatherings of different sizes in counties across the United States.


The risk-assessment tool is the brainchild of Joshua Weitz, a quantitative biologist at Georgia Tech. The first version was a graph that crossed the number of infections per capita in any given county with the size of a proposed event. Later, that information was overlaid on a map to make it more user-friendly.

Here’s how it works: Say you’re thinking of attending a Friendsgiving dinner. You open the tool, move the slider on the left of the map to reflect the number of people you expect to attend, then hover your cursor over the county where the event will take place. The tool will then tell you the percent chance that you’ll come into contact with a coronavirus carrier — assuming the event were held today.

The tool can tell you the risk, be it 6% or 60%, but it can’t tell you whether that risk is worth taking. That decision is up to you.

“In a way it’s like a weather map,” said Clio Andris, a professor of city and regional planning and interactive computing at Georgia Tech who helped Weitz build out the tool. “It can tell you what the risk is that it will rain, but it can’t tell you if you’ll get wet. That depends on if you carry an umbrella, or if you choose not to go outside at all.”

The map is updated daily with the latest case numbers for every county in the U.S. — again, just like a weather forecast.


Andris herself used the tool to decide whether to attend a small election-watching party with four friends last week. She plugged in the numbers and found there was a 4% chance that one of the guests would arrive with a coronavirus infection and potentially transmit it to others.

That 4% chance wasn’t necessarily low enough for Andris, who has taken pandemic precautions seriously. But then she considered that the four other attendees were professors who mostly lived alone and hadn’t socialized much since the outbreak began.

Evaluating the guest list helped Andris make her decision to go. And that type of personal assessment is something no map can do for you, Netburn writes — at least, not yet.

By the numbers

California cases and deaths as of 6 p.m. PST Wednesday:

More than 995,500 confirmed cases and more than 18,100 deaths.
(Los Angeles Times Graphics)

Track the latest numbers and how they break down in California with our graphics.

See the current status of California’s reopening, county by county, with our tracker.

A map of California showing the tiers to which counties have been assigned based on their local levels of coronavirus risk.
A description of the four tiers California uses to determine when counties can let businesses open, based on coronavirus risk

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Across California

How close is California to passing 1 million coronavirus infections? To answer that question, please take your thumb and your index finger and hold them a fraction of an inch apart. Yes, this close.

As of 6 p.m. Wednesday, the state had reported more than 995,500 confirmed cases and just over 18,100 deaths. And so far, the state has averaged 6,377 new cases per day over the last week. The grim milestone is expected to be reached Thursday.

And that isn’t even the biggest worry on public health officials’ minds right now. They’re concerned about the near future, when people may be gathering for Thanksgiving and Christmas, giving the virus even more opportunity to spread.

California had seemed to escape the third wave of coronavirus spikes hitting several regions around the U.S. Starting in July, the Golden State recorded 12 straight weeks of declining COVID-19 hospitalizations. Last month, that began to change.

Tuesday saw about 3,224 COVID-19 patients hospitalized, a roughly 38% increase compared with two weeks before. The number of infected patients in intensive care — 889 — is up 34% from that time too.

The coronavirus positivity rate has climbed as well, from 3.8% to 5.3%. All these trends are leading public health officials to worry that California is going in the wrong direction just as we head into the potentially dangerous holiday season.

In Los Angeles, Mayor Eric Garcetti has warned residents that the next two weeks will be crucial in determining whether the current surge will be a passing problem, or continue into the holiday season.


Based on contact tracing data, 10% of those who tested positive in the last week had been to a gathering with more than 10 people, Garcetti said.

“I want to be very clear,” he said. “If you’re hosting gatherings at your house ... you may be spreading the virus.”

Remember, it’s OK to sit Thanksgiving out this year, especially if you’re trying to reduce the risk of transmission for yourself and for loved ones. If you need to find the words to gracefully bow out of these family occasions, check out the reader question in this recent newsletter.

When it comes to handling the coronavirus, San Francisco was the model. America’s second-most-dense city had somehow managed to keep infection rates and cases low, partly by taking a go-slow approach to lifting restrictions on businesses, schools and other organizations.

But now, as the coronavirus gains momentum around the state, San Francisco has not been immune. So city officials are once again being proactive, implementing new rules on their own instead of waiting for things to get bad enough for the state’s restrictions to kick in.

Alarming as it is, the surge in San Francisco was in some ways predictable, experts said. When disease rates fall, “people take a few more risks,” said Dr. Kirsten Bibbins-Domingo, chair of UC San Francisco’s department of epidemiology and biostatistics.

“We have to be even more cautious when we’re about to engage in activities that can really increase viral transmission,” she said. Otherwise, things “can quickly get out of control.”

She’s not kidding. Since late October, new daily infections have risen by 150% in San Francisco. If this pace continues, the city is on track to see its daily number of new coronavirus infections multiply by a factor of 10 — from 32 cases a day in late October to 300 cases daily by the end of the year.



— For general safety, wash your hands for at least 20 seconds (here’s a super-fun how-to video). Stop touching your face, and keep your phone clean. Practice social distancing, maintaining a six-foot radius of personal space in public. And wear a mask if you leave home. Here’s how to do it right.
— Watch for symptoms including fever, cough, shortness of breath, chills, repeated shaking with chills, muscle pain, headache, sore throat and loss of taste or smell. If you’re worried you might be infected, call your doctor or urgent care clinic before going there.
— Need a COVID-19 test? Here’s how to receive a free test if you’re in L.A. County. And here’s a map of testing sites across California.
— Here’s how to care for someone with COVID-19, from monitoring their symptoms to preventing the virus’ spread.
— If your job has been affected by the pandemic, here’s how to file for unemployment.
— Here are some free resources for restaurant workers and entertainment industry professionals having trouble making ends meet.
— Advice for helping kids navigate pandemic life includes being honest about uncertainties, acknowledging their feelings and sticking to a routine. Here’s guidance from the CDC.
— In need of mental health services? Here are resources for coping during the crisis from the CDC and the L.A. County Department of Mental Health. L.A. County residents can also call (800) 854-7771 or text “LA” to 741741.
— For domestic violence victims, the pandemic can pose a “worst-case scenario,” advocates say. If you or someone you know is experiencing such abuse, call the National Domestic Violence Hotline at 1-800-799-SAFE (7233) or L.A. County’s hotline at 1-800-978-3600. Here are more ways to get help.

Around the nation and the world

If California hits 1 million cases tomorrow, it won’t be the first state in the union to do so. Texas did it today, with 1,010,356 cases and 19,337 deaths since the pandemic began in early March.

The true number of infections there is likely higher than the official figure suggests, since many people have not been tested. Tuesday alone saw 10,865 new cases, breaking the one-day record set back in July. Among the worst-hit regions: the Laredo and El Paso areas, as the border regions struggle with recent surges in cases.

Texas isn’t alone. The U.S. at large set a new record for COVID-19 hospitalizations Tuesday, with 61,964 receiving inpatient care. And more than 1 million new coronavirus cases have been confirmed in just the first 10 days of November.

Indeed, the current surge of infections is bigger and more widespread than the ones the country experienced in the spring and summer, experts say. And this one could turn out to be far worse.

Continuing to relax rules about masks and social distancing could lead to as many as half a million more Americans dying of COVID-19 between now and the end of February, recent research shows. That’s on top of the roughly 240,000 COVID-19 deaths we’ve already suffered.

In this environment, waiting for “herd immunity” through a vaccine or through natural exposure, as some have suggested, is simply not an option.

It’s like watching an enemy drop bombs on our homes and thinking, “Well, they’ll run out of bombs eventually,” according to Dr. Michael Mina, an infectious disease specialist at Harvard.

“If this was an actual war that was killing 200,000 people, we would be building bombers, we’d be building missiles,” Mina said.

Here are a few things experts say will actually help us reduce infections and save lives:

  • The widespread use of rapid tests that can be administered at home.
  • More robust contact-tracing efforts.
  • Wearing masks every time we leave home.
  • Remaining socially distanced from those outside our households.
  • Avoiding the three Cs: close contact, closed spaces and crowds.

Virus fatigue is real, and it’s causing us to let our guard down. But if we all start making better choices, we have the potential to alter the pandemic’s course, said Nicholas Reich, a professor at the University of Massachusetts in Amherst who has been developing models of the virus’ spread for the Centers for Disease Control and Prevention

“So much depends on how we as a society respond,” he said. “The only thing that is inevitable here is that human behavior is hard to influence, and fatigue is a real thing.”

Your questions answered

Today’s question comes from a reader who wants to know: How accurate are coronavirus tests when given to asymptomatic individuals?

This San Diego County reader says she wants to see her son in Los Angeles for Christmas, and she’s hoping they can meet mask-less if he gets tested beforehand and it comes back negative. (Presumably, she’d have a negative test result to share too.)

Here’s the problem: Every coronavirus test is new because the virus itself is new, and we don’t yet know how well these tests perform in every scenario, said Dr. Benjamin Mazer, a pathologist at Johns Hopkins University.

First, a little about the types of tests out there. PCR tests are the ones that are sent off to a lab to look the virus’s genetic signature. The U.S. Food and Drug Administration says that if a PCR test signals an infection, it’s “usually highly accurate.” But that doesn’t mean they’re perfect. In cases where an infection is missed, it’s typically because the patient’s sample wasn’t collected properly, Mazer said.


Antigen tests, which provide quicker results, miss more infections — perhaps 2 out of 10 symptomatic infections and at least half of asymptomatic infections. These are rough estimates. There is some debate about whether those “missed” infections represent cases that are truly infectious toward other people, Mazer said.

“The idea is that if the antigen test is negative, then the viral load of the person is low enough that they won’t be able to pass on the virus,” he explained. “There is some truth to this, but we simply don’t know at what level of virus someone is or isn’t infectious.”

Mazer has a strategy for dealing with the uncertainty.

“When it comes to using tests to make decisions about holiday gatherings, here’s my personal opinion as a doctor: There is no test that will be safer than simply not gathering,” he said. “I’m not a public health expert, but the experts tell us that indoor gatherings, maskless gatherings and gatherings with lots of talking, eating and drinking are the highest risk.”

Our reporters covering the coronavirus outbreak want to hear from you. Email us your questions, and we’ll do our best to answer them. You can find more answers in our Frequently Asked Questions roundup and in our reopening tracker.

For the most up-to-date coronavirus coverage from The Times over the weekend, visit our homepage and our Health section, sign up for our breaking news alerts, and follow us on Twitter and on Instagram.