As far as the United States is concerned, roughly six million people have been infected with the virus, but their reactions to it are vastly different.

Some who test positive have several symptoms, like fevers, coughing, fatigue, loss of taste or smell.

Others have none at all.

In fact, the Centers for Disease Control recently said it's best estimate was that 40 percent of the people who catch COVID-19 have no symptoms.

That makes it harder to track, harder to keep from spreading and harder to gauge in terms of its deadliness.

Some estimates show that while the seasonal flu is deadly in 0.1 percent of cases, coronavirus (COVID-19) is deadly in almost 0.6 percent of cases, so it does appear to be significantly more deadly than the flu.

But the vast majority of people who get either virus recover.

I'm Will Ripley in Hong Kong.

It's day one of the city's mass testing drive.

They're trying to test the entire population--more than seven million people--over the next 14 days.

But a lot of people are not turning out.

Fewer than one million people have signed up so far.

Pro-democracy activist, Joshua Wong, says people's DNA could be sent to mainland China because Chinese experts helped set up testing centers like this one.

I'm Matthew Chance in Moscow and it's the first day of school here, the first day since March that Russian classrooms have reopened, amid the COVID-19 pandemic.

Teachers are meant to be among the first to benefit from Russia's new coronavirus vaccine.

But what we're learning is that few, if any, have so far taken up the offer to be vaccinated.

In fact, one Russian teacher's union has started an online petition, calling on members to reject it outright on safety grounds.

Well, the vaccine was fast tracked to get it to frontline workers as soon as possible.

But unfinished human trials and a lack of published clinical data means that many teachers at least see there's a risk they're unwilling to take.

I'm David Culver in Beijing, where across the country here, most students returned to the classroom on Tuesday for what is the official start of school here in China.

In most major Chinese cities, students and staff will wear masks, and they'll stagger schedules so as to allow for social distancing.

But surprisingly, in Wuhan, more than seven months since the outbreak there, the measures are arguably the most relaxed in all of China.

Students are encouraged to bring a mask, but they do not have to wear it, a sign that the city leaders apparently feel confident in their testing and contact tracing, though already on social media, some parents expressing a bit of unease, hoping this does not lead to a resurgence.

Yesterday, the sheriff of Kenosha County, Wisconsin said the previous five days had been closer to normal, that the recent protests there had been peaceful and that local officials were very, very thankful for that.

Tensions have been high in the city of Kenosha since a black man named Jacob Blake was shot by a white police officer named Rusten Sheskey on August 23rd.

Blake survived the shooting, but his family says he's paralyzed from the waist down.

A couple of different accounts have come out about exactly what led to the incident, and the Wisconsin Department of Justice is investigating.

Some of the protests that followed were violent, with demonstrators burning cars and buildings.

The state deployed the National Guard to help preserve safety and peace there.

On Tuesday, US President Donald Trump traveled to Kenosha.

He planned to meet law enforcement and National Guard troops there.

Tour areas that were damaged in the protests and participate in a discussion focused on community safety.

Officials in Wisconsin had a mixed reaction to the visit.

Governor Tony Evers, a Democrat, asked the president not to come, saying the city needed time to heal.

But US Congressman Brian Style, a Republican, said the president's visit would help the healing process.

The Kenosha News reported that Jacob Blake's family planned a rally for Tuesday afternoon at the site of the shooting.

It was set to include a food drive, community cleanup and voter registration booth.

10-second trivia!

Which of these U.S. cities has the largest population?

Seattle, Washington; Jacksonville, Florida, San Antonio, Texas; or San Francisco, California?

With more than 1.5 million people, San Antonio is the most populated city on this list.

The question is, will the ripple effects from the coronavirus pandemic change American cities as we know them?

In yesterday's show we examined some of the impacts of working from home on the people who do it.

Today, we're looking at the impacts of working remotely on the cities that are home to large office buildings.

Now, this is assuming that working from home sticks. As we mentioned on Tuesday, some companies that have tried this in the past eventually asked people to return to the office.

But if they don't ...

Telecommuting goes back 40 years.

This equipment here will allow him to carry on normal business activities without ever going to an office away from home.

Jack Nilles was a rocket scientist and he was just coming off a rocket project and somebody challenged him:

Hey, if you could put a man on the moon, why don't you fix the problem of traffic?

And he said, "Okay, I will."

And at the time it was, "Oh, this is going to change the world, we're all gonna work remotely."

That didn't really happen.

Only about 4 percent of the U.S. workforce works at home, halftime or more.

And that's about to change.

The list of companies committed to some version of permanent work from home is growing.

And many employees want that flexibility.

In the U.S., 88 percent say they want to continue working from home at least part of the time, and the sweet spot is two to three days a week.

It's a sweet spot for employers too, because at that point they can start to reconstruct their office space to be used for collaboration and communication, recognizing that home can be the place for concentration.

A recent survey found that 68 percent of large company CEOs plan to downsize their office space, and that will likely be a massive blow to major cities.

Cities do not exist without commerce.

They are effectively like marketplaces on steroids.

And they're a really critical component of the modern economy.

And the ripple effects of workers staying home impact more than just commercial real estate.

Same difference for all of those urban retailers that service workers during a daily basis.

So that's everything from your deli to your local drugstore.

To even bright entertainment complexes that serve workers both during the day and certainly after it.

Major impacts on transportation and to your highways and roadways,

which in theory, is great news for the people who continue to travel, but is a major impact for the state and local governments that rely on gas tax receipts that actually helped make sure to maintain the quality of those roads.

And even more profound impacts on our public transportation systems, of which metropolitan New York City has seen just, really, really tragic numbers at scale.

But transit agencies all over the country, even in small metropolitan areas, have been hit really hard by this feature.

But what might be a rough transition for the largest metropolitan areas, the rest of the country could stand to benefit.

People are already moving out of cities, in part because of COVID (COVID-19), but in part because they think that in the future they're going to work from home and they want to live in a place that's cheaper.

We're probably going into a recession, so companies are gonna be looking at the opportunity for reducing costs.

We have been talking at the Brookings Metro Program for years now about the idea of superstar cities porting if you will, so much of the economic gains for the nation.

And what ... where that leaves the other markets that in many ways have been on the outside looking in,

now would be attractive for them to bring in new workers, to bring in those higher incomes and (for those higher incomes) to circulate in their economies.

But it's not a given on what scale workers will do this.

What we know for sure is that there is a plentiful supply of other metropolitan areas that can offer a different kind of basically quality of life and certainly cost of living.

I think it's reached now a groundswell.

The genie is out of the bottle.

I think that as these big companies say: This is what we're going to do.

We're gonna have people working from home.

If you're not on board, you're not gonna be able to hire the people you need.

You're not gonna get the best and the brightest from around the world, and that's going to affect your bottom line.

We're still years away from saying: "Sure, I'll drive right over, I should be landing in 15 minutes."

But the Japanese company that made this hopes that will be a reality in 2023.

It has eight motors that is about the size of two regular cars.

Its maker says it's the world's smallest electric vertical takeoff and landing vehicle.

It still needs more safety and technology tests, and we have no idea how much it'll cost.

But it's got an awesome name.

Cartivator.

Well, it is "car-ptivating," it's "car-ismatic," it's state of the "cart" and it "car-ptures" a lot of interest.

It's "car-pelling" to look at, and it could be the "cars" (cause) of new developments.

I mean, all in all, I'd say it's pretty fly, y'all.

I'm Car-l Azuz for CNN 10.

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What's not to "lake" about it?

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