We just heard that UK Prime Minister Boris Johnson is in the I C about 10 days after starting to show symptoms.

Does that seem typical of how this can progress in serious cases?

Yeah, that is pretty typical.

You first start with a confident fever and about a week we can have in many people on average, develop shortness of breath.

And that shortness of breath is probably what led to his topless hospitalization because they said he needed oxygen when he was admitted to the I.

C U.

So I think that's why I'm taking a precaution.

But again, this virus, this is the natural course of the virus.

And the next week we can have will tell how he progresses, either improvements or further deterioration.

So we just have to train hope that he recovers.

Indeed, so New York Governor Andrew Cuomo said today that there are some good signs of the states.

Curve is flattening.

What do you make of the data coming out of this state?

And what does it tell us about where we're going.

Yeah, I'm cautiously hopeful about the improvement of data.

The only thing is that we know from past experiences in many states in many countries that on weekends there's always a reporting low on Saturdays and Sundays.

And then it goes back to the normal regular recording on weekends weekdays.

So I'm hopeful that lookin trend continues, but I want to see several more days of continued drop before I feel confident that the numbers air, really.

And why do you speculate that is about the weekends?

Well, it's just, you know, people, sometimes just up to not to go to the hospital then or there's less staffing.

And then the hospitals are much more basically stress.

Like, for example, there was one hospital E R.

Midnight shift yesterday in New York that only five of the 25 usual shift nurses showed up for that shift.

That's a lot of absenteeism or potential illness, so I'm hopeful.

I want to see the whole weeks data before I am start cheering for victory will be flying the Kurt, and we also have to crush the car a lot more before we can really claim a lit right before we consent Llobregat in anyway.

So we're seeing the number of cases globally and in the US continue to soar.

Is that partially because of increased testing, or do you think that we still need to be doing more testing?

We definitely need to do more.

Testing.

Testing testing is always good, and what would be even better is as you increase your tests, the number percent positive starts dropping.

That would be a good sign, but so far that has not been happening everywhere which you need is not just hospital testing, which right now in New York City is restricting, too.

If you're hospitalized, will give you a test.

If you're not hospitalized, we're not giving your test.

That's not what you need.

You need to test people as soon as they develop symptoms out the outpatient centers because as soon as you do that, you could isolate them, contact, trace them and finally put out the fire.

Because right now all the lockdowns for on Lee just slow the fire won't put out the fire.

And the director of the CDC also said today that the death toll will be quote much, much, much lower.

Then would have been predicted by the models because of effective social distancing measures.

So what's the danger if those efforts are relaxed too soon?

Yeah, a danger is a resurgence.

Basically, you know this epidemic.

It's like time it marches forward, and it will keep marching unless you put brakes on it on a constant faces.

And our worry is that once we let off the brake, you'll get a resurgence.

And right now, China, they unlocked their lockdowns and there suddenly having a resurgence of the largest number they have had in over a month.

So we have to be very careful.

It's not just mitigation, but also testing of brand new cases as soon as they to disappear, not just testing at the hospital.

And lastly, doctor, more people are wearing masks now, after the new CDC guidance late last week.

What kind of effect or mass gonna have at this stage in slowing the spread?

I think master really good, because it actually stops your spread to other people because we're still constantly going to doctors, offices, pharmacies, parks as well, and grocery stores and grocery stores.

It's really hard to maintain your distance, and there's thousands of people go through the grocery stores each day, so the mass actually prevents you spraying your droplets everywhere and that is actually good.

That is a really, really effective for preventing people from spreading into others always so helpful to have you on Dr Fei building.

We thank you for your insight.

Hi, everyone.

George Stephanopoulos here.

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