The warning from the governor there just weeks after thousands celebrated Mardi Gras and the death toll in the U.

S.

Including a 34 year old man.

Here's NBC's Kaylee Hartung Tonight, back reporting for us after recovering from the corner virus herself tonight.

The virus taking its toll.

Jeff Ghazarian, just 34 years old, one of hundreds to dying in the U.

S.

He just had ah lot of love and humor and could approach and talk Thio anybody Ghazarian loved ones say the cancer survivor was on a ventilator for five days before losing his battle late last week in California.

The dire warning now being sounded in Louisiana confirmed cases tripling since Friday to roughly 1400.

Don't go out unless you absolutely have to.

The virus is here, and everyone needs to act as if they have it.

Just four weeks ago, the entire city of New Orleans and thousands of tourists celebrating Mardi Gras at least 270 now hospitalized across the state, many needing critical care.

It's like I'm staying the shore.

I'm watching a tsunami coming in, but it's coming in a very slow pace, and I and we try to prepare, but I know it's gonna be coming tonight.

Thousands with the virus under quarantine.

After reporting from the nursing home in Washington state that was overrun with cases, I began to feel symptoms.

My body A KT.

I had chills and a headache.

I took this video in the emergency room, just came back to tell me I'm going to be tested.

Those results were gonna take 5 to 7 days, got a lot of or in thine time ahead.

By the time I received my positive test results, my symptoms have mostly faded.

28 year old Matt Robertson, from Shoreline Washington, spent two weeks in the hospital, at times unconscious and on a ventilator.

He's now rebounding, doing physical therapy to regain his strength.

The case could have been more tragic, and that there was, you know, that chance that I could have not made it through this.

Kaylee Hartung joins us now from her home, where she continues to quarantine as she gets better from this in Kelly, I know you reported last night.

How much better you're feeling already as you prepare to finish your time in isolation.

But what if your doctors told you?

What are we hearing from the CDC so far about folks like you who've had it about any potential immunity you might have going forward?

David, Officials at the CDC.

You're talking about the need to test those of us who've had the virus to determine if we can get it again or continue to spread it right now.

There is so much unknown about the virus, including when that immunity develops.

David or Kaylee Hartung.

Thank you.

Hi, everyone.

George Stephanopoulos here.

Thanks for checking on ABC News YouTube channel.

If you'd like to get more video show highlights and watch live event coverage, click on the right over here to subscribe to our channel.

And don't forget the download.