6 Things You Might Not Know About Ebola

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There's been a new outbreak of Ebola in the Democratic Republic of the Congo. Eleven people have been sickened by the disease, and one has died. Here are some things you might not have known about Ebola.

1. THERE'S MORE THAN ONE KIND OF EBOLAVIRUS.

Five species of Ebolavirus have been identified, each named after the place they sprung up: Ebola (formerly Zaire), Bundibugyo, Sudan, Taï Forest, and Reston. All but one—Reston—arose in Africa. The Reston subtype is named after a town in Virginia where an outbreak occurred in 1989, followed by incidents in Texas and Pennsylvania; all three were tied to infected monkeys exported by a single facility in the Philippines. All Ebolavirus species affect people and nonhuman primates—monkeys, gorillas, and chimpanzees—but Reston doesn't cause detectable disease in humans.

2. EBOLA HIJACKS THE IMMUNE SYSTEM.

Researchers are finding out just how clever Ebola is. One key to its lethal success is the stealth way it shuts down immune system defenses, the same way an air force will disable air defenses before sending in the bombers. Ebola obstructs parts of an immune system that are activated by molecules called interferons. These interferons have a vital role in fighting Ebola, usually with scorched-earth tactics such as apoptosis, or cell self-destruction. A 2014 study found that Ebola disables signals the cells use to defend against its attack using a protein called VP24, which binds to a specific protein that takes signaling molecules in and out a cell's nucleus. Blocked from communication, the cell can't call for help or get the order to self-destruct. The virus then hijacks the cell, uses it to make more viruses, and spreads them to more cells. It also produces ebolavirus glycoprotein, which binds to cells inside blood vessels, increasing their permeability and leading to leakage. This contributes to the catastrophic bleeding characteristic of late-stage Ebola infection.

3. BATS ARE THOUGHT TO BE THE KEY HOSTS OF EBOLA.

CDC illustration of cycle of ebola infection from bats to humans and animals

Scientists believe that Ebola's natural host species, or "reservoir hosts," are bats. Infected bats can pass the virus to other mammals, including rats, primates, and us. No one is sure how people first became exposed to Ebola, but the best guess is that monkeys were the conduit. Local hunters in Africa likely became infected while butchering the animals. Anyone who became sick likely infected their family and, if hospitalized in an unsanitary facility, other patients. When the illness spreads from person to person, it does so through direct contact with the bodily fluids of someone who is sick with or has died from Ebola.

4. MEDICAL DETECTIVE WORK IS THE ONLY WAY TO STOP AN EBOLA OUTBREAK.

It takes the investigative skill of a homicide detective to stop an outbreak. Professionals call it contact tracing. Here's how it works: Ebola victim A is isolated and interviewed. Anyone who had close contact with A is put into quarantine for 21 days. If they exhibit no symptoms, they're free to go when the three weeks are up. If they come down with Ebola, they become victim B, and another contact trace begins. If the investigators miss anyone, the outbreak will continue.

5. HAVING MALARIA AND EBOLA AT THE SAME TIME MAY HELP PEOPLE SURVIVE.

Researchers analyzing the the 2014 outbreak of Ebola in West Africa made a surprising finding: patients who had an active malaria parasite infection were actually more likely to survive the Ebola virus, and by a significant degree. While just over half (52 percent) of Ebola patients not infected with malaria survived, those co-infected with malaria had a survival rate of 72 to 83 percent, depending on their ages and the amount of Ebola virus in their blood. The researchers aren't yet sure why, but the prevailing theory is that malaria somehow modifies the immune response to Ebola by toning down a phenomenon called the "cytokine storm"—the body's own response to an Ebola infection, which inadvertently kills the host while attempting to eliminate the pathogen. If malaria can dampen this response, infected patients may have a better chance of surviving.

6. IF YOU'RE A SCIENTIST, YOU CAN ORDER EBOLA ONLINE.

We do not yet have a vaccine or antiviral drug to treat Ebola, but many scientists are working to find one. One source is the National Institute of Allergy and Infectious Diseases (NIAID)'s BEI Resources, which gives research facilities access to microbiological materials called reagents that can help them develop diagnostics and vaccines for emerging diseases, including Ebola. Scientists must be registered with BEI to request materials. Reagents are not active viruses, so they can't spread; on the biosafety level, or BSL, scale—which ranks the severity of infectious disease and sets required safety protocols for working with them in a lab—the Ebola-related reagents are considered BLS 1—the lowest risk. (Live Ebola virus is BLS 4—the highest.) Ordering is limited to one Ebola-related reagent at a time, and can be ordered only twice per year.

One Good Reason Not to Hold in a Fart: It Could Leak Out of Your Mouth

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iStock/grinvalds

The next time you hold in a fart for fear of being heard by polite company, just remember this: It could leak out of your mouth instead of your butt. Writing on The Conversation, University of Newcastle nutrition and dietetics professor Clare Collins explains that pent-up gas can pass through your gut wall and get reabsorbed into your circulation. It's then released when you exhale, whether you like it or not.

“Holding on too long means the build up of intestinal gas will eventually escape via an uncontrollable fart,” Collins writes. In this case, the fart comes out of the wrong end. Talk about potty mouth.

A few brave scientists have investigated the phenomenon of flatulence. In one study, 10 healthy volunteers were fed half a can of baked beans in addition to their regular diets and given a rectal catheter to measure their farts over a 24-hour period. Although it was a small sample, the results were still telling. Men and women let loose the same amount of gas, and the average number of “flatus episodes” (a single fart, or series of farts) during that period was eight. Another study of 10 people found that high-fiber diets led to fewer but bigger farts, and a third study found that gases containing sulphur are the culprit of the world’s stinkiest farts. Two judges were tapped to rate the odor intensity of each toot, and we can only hope that they made it out alive.

Scientific literature also seems to support Collins’s advice to “let it go.” A 2010 paper on “Methane and the gastrointestinal tract” says methane, hydrogen sulfide, and other gases that are produced in the intestinal tract are mostly eliminated from the body via the anus or “expelled from the lungs.” Holding it in can lead to belching, flatulence, bloating, and pain. And in some severe cases, pouches can form along the wall of the colon and get infected, causing diverticulitis.

So go ahead and let it rip, just like nature intended—but maybe try to find an empty room first.

[h/t CBS Philadelphia]

A Chemical in Spider Venom Could Be a Key to Killing Skin Cancer Cells

Alan Couch, Flickr // CC BY 2.0
Alan Couch, Flickr // CC BY 2.0

Despite their formidable reputation in the eyes of arachnophobes, spiders contribute to human society in a number of positive ways. On a practical level, they can reduce the population of insects in your home by trapping them for meals. Outdoors, they keep pests from destroying gardens and crops, making sure we don't slip into a period of famine and anarchy. In the lab, scientists have identified a number of chemicals in their venom as possible building blocks for medicines treating everything from pain to muscular dystrophy.

That field of study has led to a promising discovery. In Australia, researchers have isolated one particular compound in a funnel-web spider's venom that can diminish skin cancer cells.

Scientists at QIMR Berghofer and the University of Queensland began studying the Australian funnel-web spider known as Hadronyche infensa after a similar Brazilian arachnid, Acanthoscurria gomesiana, was shown to carry a peptide in its venom called gomesin that has cancer-fighting properties. Identifying a similar peptide in the Australian spider, the researchers demonstrated that the chemical was effective in killing skin cancer cells while leaving healthy skin cells alone.

The peptide was tested on human melanoma cells, eradicating the majority of them. In mice, it also slowed the growth of the melanomas. The peptide was even effective in killing cells found in facial tumors of Tasmanian devils, a marsupial susceptible to an aggressive form of skin cancer transmittable through biting. The results were published in the journal Scientific Reports.

These peptides are able to be manipulated, taking on different properties as scientists alter amino acids to create new and potentially more potent versions. It’s hoped that this line of research will lead to the development of treatments for skin cancer in humans.

It's something to think about the next time you consider swatting a spider—though if you happen to reside in Australia and see the funnel-web variety, you might not have a choice. While there are 35 different species of funnel-webs of varying potency, some are so formidable that their fangs can pierce fingernails, and their venom is able to kill a human in less than 15 minutes.

[h/t New Atlas]

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