6 Fast Facts About Brain-Eating Amoebae

iStock.com/Dr_Microbe
iStock.com/Dr_Microbe

If “brain-eating amoebae” isn't the most terrifying combination of words you’ve ever heard, it will be by the time you finish reading this article. Although infection from the Naegleria fowleri amoeba is rare, it does happen from time to time. Just last month, a 29-year-old man died from a brain-eating amoeba after visiting a wave pool in Waco, Texas. The CDC is currently investigating the incident. Here are a few things you should know about this pernicious organism.

1. THEY LIVE IN WARM FRESH WATER.

Warm bodies of fresh water like lakes, rivers, and hot springs are usually where the single-celled amoebae like to hang out. They can also be found in soil, and in extremely rare cases, in contaminated tap water or swimming pools that haven’t been properly chlorinated. While most people encounter the amoebae in lakes or rivers, the CDC reports found that between 2007 and 2016, one person became infected after using a backyard slip-n-slide and three people became infected after using a nose irrigation device. Contaminated tap water was to blame in all four cases.

2. YOU WON’T GET INFECTED FROM SWALLOWING CONTAMINATED WATER, THOUGH.

Infection only occurs when water containing Naegleria fowleri enters the nose. In other words, accidentally swallowing river water while swimming doesn’t put someone at risk, but getting water up one’s nose does. Although the presence of Naegleria fowleri in fresh water is common, infections still remain rare.

3. THEY’RE NOT USUALLY ATTRACTED TO HUMANS.

These amoebae don’t go out of their way to feast on human brains. In fact, they’re usually content to eat bacteria found in the soil or sediment of lakes or rivers. “Normally, it’s totally harmless, doing its own thing in the mud, eating whatever it finds there, going about its business, not bugging anybody,” biologist Dan Riskin told Mental Floss in 2017. However, once it enters a new environment (such as an unsuspecting victim’s nasal cavity), it resumes eating whatever it can find.

4. AFTER ENTERING THE NOSE, THEY TRAVEL UP THE OLFACTORY NERVE.

Once inside the nasal cavity, an amoeba starts eating away at the olfactory bulbs, which are responsible for processing information about odors. “It makes its way up that olfactory nerve, reproducing and eating, until it hits the brain,” Riskin said. “And once it’s in the brain, it’s game over for the kid that had it shoved up his nose.” That’s because the amoebae eat brain tissue and cells, resulting in brain swelling, necrosis, and usually death.

5. THE DISEASE IT CAUSES IN HUMANS IS ALMOST ALWAYS FATAL.

Once infected, a disease called primary amebic meningoencephalitis (PAM) sets in. Early symptoms include severe headache, fever, nausea, and vomiting, and some of the stage-two symptoms are seizures, hallucinations, altered mental state, and coma. Generally, people start to show symptoms about five days after infection and die five days after that. The fatality rate is more than 97 percent, but again, infection is rare. Of the 143 cases of infection reported between 1962 and 2017, only four people survived, according to the CDC. But don't worry, your odds of contracting a brain-eating amoeba are about 1 in 70 million.

6. YOU CAN REDUCE YOUR RISK BY PLUGGING YOUR NOSE.

Brain-eating amoebae shouldn't be at the top of your list of concerns while swimming—drowning, for instance, is a far greater danger—but there are still a few things you can do to protect yourself. Try squeezing your nose shut while jumping or diving, or keep your head above water while taking a dip.

Is There An International Standard Governing Scientific Naming Conventions?

iStock/Grafissimo
iStock/Grafissimo

Jelle Zijlstra:

There are lots of different systems of scientific names with different conventions or rules governing them: chemicals, genes, stars, archeological cultures, and so on. But the one I'm familiar with is the naming system for animals.

The modern naming system for animals derives from the works of the 18th-century Swedish naturalist Carl von Linné (Latinized to Carolus Linnaeus). Linnaeus introduced the system of binominal nomenclature, where animals have names composed of two parts, like Homo sapiens. Linnaeus wrote in Latin and most his names were of Latin origin, although a few were derived from Greek, like Rhinoceros for rhinos, or from other languages, like Sus babyrussa for the babirusa (from Malay).

Other people also started using Linnaeus's system, and a system of rules was developed and eventually codified into what is now called the International Code of Zoological Nomenclature (ICZN). In this case, therefore, there is indeed an international standard governing naming conventions. However, it does not put very strict requirements on the derivation of names: they are merely required to be in the Latin alphabet.

In practice a lot of well-known scientific names are derived from Greek. This is especially true for genus names: Tyrannosaurus, Macropus (kangaroos), Drosophila (fruit flies), Caenorhabditis (nematode worms), Peromyscus (deermice), and so on. Species names are more likely to be derived from Latin (e.g., T. rex, C. elegans, P. maniculatus, but Drosophila melanogaster is Greek again).

One interesting pattern I've noticed in mammals is that even when Linnaeus named the first genus in a group by a Latin name, usually most later names for related genera use Greek roots instead. For example, Linnaeus gave the name Mus to mice, and that is still the genus name for the house mouse, but most related genera use compounds of the Greek-derived root -mys (from μῦς), which also means "mouse." Similarly, bats for Linnaeus were Vespertilio, but there are many more compounds of the Greek root -nycteris (νυκτερίς); pigs are Sus, but compounds usually use Greek -choerus (χοῖρος) or -hys/-hyus (ὗς); weasels are Mustela but compounds usually use -gale or -galea (γαλέη); horses are Equus but compounds use -hippus (ἵππος).

This post originally appeared on Quora. Click here to view.

An Ice Age Wolf Head Was Found Perfectly Preserved in Siberian Permafrost

iStock/stevegeer
iStock/stevegeer

Don’t lose your head in Siberia, or it may be found preserved thousands of years later.

A group of mammoth tusk hunters in eastern Siberia recently found an Ice Age wolf’s head—minus its body—in the region’s permafrost. Almost perfectly preserved thanks to tens of thousands of years in ice, researchers dated the specimen to the Pleistocene Epoch—a period between 1.8 million and 11,700 years ago characterized by the Ice Age. The head measures just under 16 inches long, The Siberian Times reports, which is roughly the same size as a modern gray wolf’s.

Believed to be between 2 to 4 years old around the time of its death, the wolf was found with its fur, teeth, and soft tissue still intact. Scientists said the region’s permafrost, a layer of ground that remains permanently frozen, preserved the head like a steak in a freezer. Researchers have scanned the head with a CT scanner to reveal more of its anatomy for further study.

Tori Herridge, an evolutionary biologist at London’s Natural History Museum, witnessed the head’s discovery in August 2018. She performed carbon dating on the tissue and tweeted that it was about 32,000 years old.

The announcement of the discovery was made in early June to coincide with the opening of a new museum exhibit, "The Mammoth," at Tokyo’s Miraikan National Museum of Emerging Science and Innovation. The exhibit features more than 40 Pleistocene specimens—including a frozen horse and a mammoth's trunk—all in mint condition, thanks to the permafrost’s effects. (It's unclear if the wolf's head is included in the show.)

While it’s great to have a zoo’s worth of prehistoric beasts on display, scientists said the number of animals emerging from permafrost is increasing for all the wrong reasons. Albert Protopopov, director of the Academy of Sciences of the Republic of Sakha, told CNN that the warming climate is slowly but surely thawing the permafrost. The higher the temperature, the likelier that more prehistoric specimens will be found.

And with average temperatures rising around the world, we may find more long-extinct creatures rising from the ice.

SECTIONS

arrow
LIVE SMARTER