Laurel Bristow

And because it happened to get into an environment that is conducive for the spread of infectious disease, the way the close confined quarters of cruise ships are, that's why we're seeing such a kind of profound spread within people who are on this cruise in a way that we haven't really seen before.

Is it a very deadly disease?

It can be.

It depends on what kind of hantavirus it is.

But the case fatality tends to be up to 40 percent.

I think Andy's virus is 38 percent currently.

And that's because it can do things like cause pulmonary syndrome, which causes severe pneumonia that can cause people to die.

And it also can cause renal failure.

We're not sure.

That investigation is ongoing.

But I think the most likely working theory at this point is that one or two people who got on the cruise ship were infected with hantavirus on land in Argentina before they got on the ship.

And then on the ship, there was some degree of person-to-person transmission.

The first case was a seven-year-old man who passed away on the ship, and it just seemed, nothing seemed out of the ordinary.

And then, of course, two weeks later, his wife got off the ship, or his partner got off the ship, and then she became ill and died.

And on the same day that she got off, someone else became extremely ill and had to be medevaced.

And I think around that time, there started to be the suspicion that something was going on that was not just a fluke.

One of the problems with the hantavirus outbreak is that the symptoms overlap a lot with influenza.

So it's not going to be the first thing that you suspect.

Early symptoms often feel like many other common illnesses and include fever, headache, muscle aches, stomach pain, nausea or vomiting.

In these cases, you really have to think about what your actual exposure risk is with something like this.