current events. We're starting this Tuesday on the world's highest mountain. Every year since

1900 at least one person has died climbing Nepal's Mount Everest, and this year is no exception.

The 2016 climbing season has claimed its first victims. One climber died on Thursday, one on Friday,

one on Saturday, and one on Sunday. And these deaths, coming so close together, have frightened many of

the climbers who are starting their trip back down the mountain. So, why did this happen now? Well, most

people attempt to climb Everest in April and May. One reason, the winds are calmer. In other months,

there are usually hurricane force winds at the summit. There also tends to be less snow falling at this

time of year, though temperatures are still well below zero degrees Farenheit.

Mount Everest's spring climbing season has turned deadly with four deaths now in the past four days.

You have to get to 29, 000 feet to get to the top of Mount Everest, and above 26, 000 feet is called

the Death Zone. There's just not enough oxygen up there for your body to last very long. Now this is

the first real death from climbing that we've seen since they closed the mountain because of the

earthquake. Now, remember there was also the avalanche that closed part of the climbing season

2015 and 2014, so not many people have been up there.

They're also saying that there are so many people trying to get to the top because it is now opened again,

and that is slowing the ascent, and keeping those people, keeping the climbers in that Death Zone

longer, cuz it's such a slow climb to the top. Avalanches kill people. Injuries kill people from falling,

or from ice collapses. Also weather from exposure, and, of course, just altitude sickness alone

is killing people up there because of the height of Mount Everest.

But for many climbers the danger is what actually attracts them to Mount Everest. And since this years

climbing season began, about 300 people have made it to the top. We don't know yet if the recent

deaths there will impact tourism. That's a major industry in Nepal. But tragedies can significantly

impact the number of people who might want to visit a country. For example, in Egypt, another economy

that benefits from tourism, visits were down by 40 % early this year as compared to early 2015. And though

investigators aren't certain what caused EgyptAir Flight 804 to crash in the Mediterranean last week,

that event, along with some others in recent years, could deeply hurt Egypt.

This crash is a major blow to a fragile but crucial part of the economy. Egypt has been struggling

to bring back visitors really since 2010 when the number of tourists hit a record high of over 14 million.

Last year that number was about nine million. Now, obviously this decline has impacted the amount of

money visitors spend in the country, which has been slashed in half over that same time period.

Just to put this into context, tourism accounts for about 11 % of all economic activity, and 11 % of jobs

in the country are actually tied to the industry itself. This decline in tourism started in 2011 with the revolution,

the Arab Spring, and unrest after the coup that scared off a ton of people from visiting.

Visitors were actually starting to return in 2015. In fact, the Washington Post even ran a headline on it.

Then, two incidents hurt the recovery. Terrorists brought down a Russian jet just after it took off from an

Egyptian resort and then a domestic EgyptAir flight was hijacked in March. These and other incidents are

raising questions for tourists who have really been vacationing in this region for years. And for many

of these countries, especially those along the Mediterranean, tourism is a crucial part of the economy.

The World Health Organization, which is part of the United Nations, had an emergency meeting recently

to discuss an outbreak of Yellow Fever. It started in the southern African nation of Angola last December.

Since then, more than 2, 400 people have been infected, and 300 people have died from the disease.

That makes this the worst outbreak of Yellow Fever in Angola in 30 years. But it has spread to other countries.

There have been dozens of cases in the neighboring Democratic Republic of Congo and in nearby

Uganda. So what health officials are doing is directing millions of vaccines to this region.

They're hoping that will help create a barrier against the spread of this disease.

Yellow Fever is a disease caused by a virus that can make you, you guessed it, turn yellow. The virus comes

from the bite of a mosquito. And the yellow is because your liver starts to fail and you develop jaundice,

a yellowing of the eyes and the skin. You'll also get fevers, chills, back pain and generalized aching.

From infection to illness, typically takes three to six days. Now most people are going to improve after these

initial symptoms, however about 15 % will develop a more severe form of the disease. There is no

treatment or cure for Yellow Fever. Doctors are going to work to alleviate symptoms, prescribing rest, fluids,

medications. The best way to avoid Yellow Fever is to get vaccinated, especially if travelling to Africa,

South America, use insect repellant, wear thick long sleeve clothing and sleep

in a screened in or air conditioned room as much as possible.

Since the Vietnam war, the US has banned the sale of American military weapons to the communist

country of Vietnam. But yesterday, while on a trip there, President Obama removed that ban.

He says it's part of the work to normalize relations between America and Vietnam. And that that

includes more military cooperation. Critics say President Obama should have waited until Vietnam

improves its human rights record before lifting the ban. A human rights watch official says the

president gave the Asian country a reward it did not deserve. But international experts say this isn't

just about Vietnam and the US, they say China factors in. It's involved in an international dispute

over what country controls territory in the South China sea. Some US officials see Vietnam

as a balance to China's influence in the region.

From coast to coast and across the sea, it's time for the CNN Student News roll call.

We're starting in Spokane, Washington. Why? Because the pirates are there at John R Rogers High School.

Next, to the eastern US city of Westminster, South Carolina, great to see everyone at

Cherokee Creek Boys School watching today. And jumping over the Atlantic, we land in Toulouse, France,

where we're visiting our viewers at Bellevue Middle School. When you walk through a spider web,

you're probably more concerned about whether anything was on it at the time than you are impressed

by the relative strength of the structure. But a professor at Oxford University believes that spider

silk may help in fixing damaged nerves in humans and regenerating joints. For this Professor,

the webs that arachnids weave hold hope for a new silk age with advances in science and medicine.

I'm Fritz Vollrath. I work on spiders and spider webs and spider silks and on silkworm silks. Spider webs

are really, really interesting structure. For human, comparison would be like if you could make a net the

size of a football field where you sit in the center and the net could catch the equivalent of a jumbo jet.

That is pretty amazing. The question is can we use these silks, whether they're from a spider

or a silkworm, to help in regenerative medicine?

There's a lot of interest in the medical community in silks as for tissue culture, growing replacement

body parts, potentially like ears, where they're using collagen. Maybe for 3D printing things.

We can fix a nerve that's been crushed. We can connect the two ends with a sheath that's filled with spider silk.

And the nerves will grow along these spider silk threads, and connect, and then the person can

move the arm again. And now we are in human trials with some of these implants, and they seem

to work very well. I don't see, at this stage, anything that would be off- limits.

What is purple, plastic, made by a 3D printer, and can totally rock a Mozart concerto? Well here you go.

Now to be fair, this is not a Stradivarius. The girl playing it says it has a more muted sound than

a wooden violin and that there are limits to its pitch. Still, considering that it was created by

a high school senior, who is studying sound waves for a physics class, we're thinking her grade is

somewhere in the key of A. The story certainly violin's itself to puns. You could say it was worth the treble.

That with musicians and inventors alike, it resonates. We could string you along for days on

Stradivarius word plays but before you tune us out, we'll just take a bow.

CNN Student News will be on the air through next Friday, June 3. After that, our summer break begins.