Herpes and the Brain

By Anna Rothschild
Posted 06.04.15
NOVA

Herpes is probably hiding in your nerve cells right now. Learn more in this episode of Gross Science.

Running Time: 03:15

Transcript

Herpes and the Brain

Posted: June 4, 2015

Herpes. It’s way creepier than you ever thought.

I’m Anna Rothschild, and this is Gross Science.

Herpes viruses are super common and quite diverse. If you’ve ever had cold sores, chickenpox, or mono, you’ve been infected with a herpesvirus. In fact, we know of eight different types of herpesviruses that infect humans, and if you’ve had one that infection lasts a lifetime.

That’s because herpes viruses go into what’s called a “latent phase,” which is like a state of hibernation where the virus hides in your cells. And, what I find so interesting is just where these viruses are hiding. Believe it or not, the ones that cause cold sores, genital sores, and chickenpox actually hide in neurons around your body. And this can have some pretty weird implications.

For example, if you had chickenpox as a kid, the virus might flare up later in life as the disease shingles. Shingles causes a painful rash, which appears in particular locations on your skin depending on which nerve the virus was hiding in. A friend of mine once got shingles on his left butt cheek, because the virus flared up in the nerve connected to that patch of skin. It was apparently very uncomfortable.

Because herpes lurks in your nervous system, it can sometimes make its way to your brain—though this only happens to about two in a million people. On these very rare occasions, the same virus that causes cold sores can sneak into your temporal lobes and cause a host of unpleasant effects, including death. But some people who survive are left with a very strange type of brain damage. They’re totally normal, except they’ve lost the ability to recognize whole classes of things, like animals, or colors, or tools. One survivor could no longer identify whether a drawing depicted a real animal or a fictional hybrid beast. And while I wouldn’t wish brain herpes on anyone, because of its specificity, this type of brain damage has actually revealed some secrets about how our brains store and categorize information.

Anyway, scientists are learning more about these viruses all the time. In the past few years, they’ve begun to understand how to lure herpes out of the nervous system. And hopefully one day they’ll be able to stop all eight types of herpes in their tracks.

Ew.

Credits

PRODUCTION CREDITS:

Host, Writer, Animator, Editor: Anna Rothschild
DP, Sound, Intern Extraordinaire: Elizabeth Gillis
Many thanks to Dr. Bryan Cullen.
Lucky Charms: Music Provided by APM

IMAGES

Dermatomes and cutaneous nerves – posterior: Wikimedia Commons/Mikael Häggström
Herpes labialis – opryszczka wargowa: Wikimedia Commons/Jojo
Herpes zoster chest: Wikimedia Commons/Fisle
Herpesviridae EM PHIL 2171 lores: Wikimedia Common/CDC
Main symptoms of Infectious mononucleosis: Wikimedia Commons/ Mikael Häggström
Windpocken: Wikimedia Commons/Thomas Netsch

SFX

Cockroaches: Freesound/StateAardvark
(used with permission from author)
Squeak Pack/squeak_10: Freesound/Corsica_S
snoring long: Freesound/pencilgame1
Jacob’s Ladder/Jacobs ladder 007: Wikimedia Common/DJ Chronos
Wink: Freesound/bennychico11
Swishes: Freesound/pogotron
Real?_world_recordings/lake ducks squawking at night: Freesound/Tomlija
Oink: Freesound/payattention
Bubbling Popping: Freesound/Ch0cchi; Produced by WGBH for PBS Digital Studios