yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Flu Virus 101 | National Geographic


2m read
·Nov 11, 2024

  • [Narrator] The flu is a highly contagious respiratory illness. It turns up year after year with devastating consequences, all caused by a most elusive virus.

The influenza, or flu virus, is a recurring nightmare. It causes more than 36,000 deaths in the U.S. each year and was responsible for some of history's deadliest pandemics. Like other viruses, the flu virus is a parasite. The viral agent itself, called a virion, is made of ribonucleic acid or RNA surrounded by proteins.

The flu virus uses two proteins to attack its host: hemagglutinin and neuraminidase, or the HA and NA proteins. The HA protein attaches a virus to a cell and lets it in. Once the virus is inside, it multiplies. Then the NA protein cuts this viral swarm loose, sending it off to infect more cells.

This triggers the immune system to bombard the swarm and to destroy infected tissue throughout the respiratory system. Unfortunately, this response can also inadvertently lead to death through organ failure or secondary infections like bacterial pneumonia.

The flu virus has been nearly impossible to eradicate, largely due to its uncanny ability to mutate. Since just 2004, more than 5,000 different strains of the influenza virus have been sequenced. Those that affect humans are categorized as Types A, B, or C, with Type A strains being the most capable of unleashing a pandemic.

Influenza A viruses mutate more rapidly, allowing them to adapt to new hosts and even cross species. Avian flu and swine flu, for instance, are two strains of Type A viruses that, through mutations, can be transmitted from birds and pigs to humans.

One of the deadliest flu pandemics was caused by one such virus. Between 1918 and 1919, the Spanish flu infected a third of the global population and killed up to 50 million people worldwide. Called H1N1, this particular strain of virus likely came from birds.

The threat of another influenza pandemic remains. In the meantime, scientists are constantly monitoring the flu virus and developing seasonal vaccines to create our best line of defense.

More Articles

View All
My morning routine
So I’ve really avoided making a morning routine video, specifically because I feel like there’s just so many of them on YouTube, and I feel like morning routines are generally overrated. You know, everyone’s seen thumbnails on YouTube of like, “The One Mo…
Supertasks
Hey, Vsauce. Michael here. Now, one of my favorite treats of the holiday season is Gabriel’s cake. It’s a super solid based on Gabriel’s Horn that you can make right at home, as long as your home is infinitely large. Okay, all right. Now, the first thing …
Passing Obama’s Stimulus Bill | Obama: The Price of Hope
NARRATOR: Obama needs just two Republican senators to defy their party. He turns to the veteran leader of the Senate Democrats. None of the Republicans who wanted to do something to help wanted to be the 60th vote. So I had to get 61 votes on everything. …
I Spent $100,000 On A Stock Picking Monkey
What’s up you guys? It’s Graham here. So if you thought this year cannot get any more unpredictable, it just did because I have a hundred thousand dollars on the line for the sole purpose of testing an odd yet unique experiment to see whether or not a mon…
How The Internet Changed Everything
[Music] In August 1962, JCR Licklider proposed a new but monumental idea: computers that could talk to one another. A simple idea, but one whose implications resulted in a world-changing network. The first message sent over the Internet, which at this tim…
Warren Buffett: "Rule #1: Never lose money. Rule #2: Never forget rule #1."
Warren Buffett: The first rule of investment is: Don’t lose. And the second rule of investment is: Don’t forget the first rule. And that’s all the rules there are. I mean, if you buy things for far below what they’re worth, and you buy a group of them, yo…