TIME animals

8 Animal Plagues Wreaking Havoc Right Now

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The scariest diseases plaguing the animal kingdom

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When we talk about studying, controlling, or just plain worrying about pandemics, we usually think of our own, human diseases. But many other species face existential threats as well. In the wild and on the farm, through climate change, human agency, and other causes, deadly diseases and conditions are ravaging specific animal communities. Here are eight of the scariest diseases plaguing the animal kingdom today.

Plague: White-nose syndrome

Target: Bats

This disease is named for the characteristic fuzzy white bloom found on the muzzles (as well as the wings and ears) of hibernating bats infected with the fungus Pseudogymnoascus destructans. The fungus seems to have originated in Europe, where it does not harm the native bats. Since it was first documented in New York in 2006, white-nose syndrome has killed an estimated 6.7 million bats in 25 U.S. states and 5 Canadian provinces. Scientists believe bats primarily contract the disease from one another, though it’s also possible bats can pick up spores from contaminated cave surfaces. Some human cave explorers may also transport fungal spores in their clothing and equipment. There’s no known cure, and the disease is incredibly deadly, usually killing between 70 and 90 percent of bats in a hibernating group; scientists are still trying to figure out exactly how the fungus kills bats, and why European bats seem to be immune.

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Plague: Canine distemper virus

Target: Tigers (and dogs, and other canines)

The virus that causes canine distemper is related to measles. It spreads through respiration, but quickly attacks the nervous system and gastrointestinal tract. The virus can also jump to big cats, and is cropping up in tiger populations across the world. In just five years, one population of tigers in Russia dropped from 38 individuals to 9; traces of CDV found in two dead tigers led scientists to finger the virus as the chief suspect in the population crash.

A recent study highlights how smaller populations of tigers are extremely vulnerable to CDV. Tigers are not abundant enough to act as reservoirs for the virus, so researchers think the key to preventing CDV from spreading amongst them is to target the canine species that are the sources of outbreaks. India is contemplating a massive dog vaccination campaign against the virus; the drive is already underway in villages near tiger reserves.

Plague: Starfish wasting disease

Target: Starfish

Over the past 40 years, starfish populations have been stricken by recurring outbreaks of a devastating condition. At first, a starfish’s limbs start to curl, then twist and fall off. Eventually, the wasting disease ravages the entire starfish, turning it into a mushy goo.

Researchers previously blamed this “starfish wasting disease” on environmental changes, like pollution or fluctuations in ocean temperatures. But a new study pins the blame primarily on a type of waterborne virus called a densovirus. One of the chief lines of evidence to support this theory was the fact that captive starfish in aquariums suddenly contracted the disease—except for those starfish in aquariums filled with UV-treated water, which kills viruses. The researchers also found higher genetic traces of the virus in diseased starfish tissue, and found that healthy starfish infected with densovirus would develop the disease within a week or so.

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Plague: Brucellosis

Target: Bison, cow, elk

The bacterial disease brucellosis causes a wide range of symptoms in animals, from arthritis to inflamed joints to reproductive trouble. It can also spread to people via unpasteurized dairy products, causing fever and flu-like symptoms as well as arthritis. While brucellosis has largely been eradicated from cattle in the U.S., the disease persists in the bison and elk of Yellowstone National Park. Fears that the wild animals could reintroduce brucellosis to nearby cattle have been bolstered by 17 documented transmissions of the disease from wildlife to livestock in the greater Yellowstone area from 2002 to 2012. Despite protests from conservation groups, park officials are planning to cull up to 900 bison from the herd this winter to stem the spread of brucellosis and stabilize the population.

Plague: Colony collapse disorder

Target: Honeybees

Starting in 2006, beekeepers in the U.S. began to notice what looked like a honeybee version of the Rapture: At once, most or all of the adult worker bees in the colony vanished without a trace, leaving behind empty hives and queen bees bereft of subjects. Colony collapse disorder, as the phenomenon came to be known, is not entirely new to beekeeping, but the magnitude of losses is unprecedented. The root cause of CCD is still unknown: Pesticides, viruses, mites, fungi, antibiotics and other factors have all been proposed.

Most scientists think CCD is prompted by a combination of factors, and that it may not directly kill the bees outright. University of Maryland bee expert Dennis van Engelsdorp explained, in National Geographic: “You don’t die of AIDS; you die of pneumonia or some other condition that hits when your immunity is down. Once the bees’ immune defenses have been weakened, “we’re pretty sure in all these cases, diseases are the tipping point.” Hive losses are still being felt across the country, but the rate of collapse seems to be slowing. According to the USDA, the loss rate in honeybee colonies nationwide over the 2013-2014 winter from all causes was 23.2 percent—still above what beekeepers consider sustainable, but less dire than the 30.5 percent losses of the 2012-13 winter, or the 8-year average annual loss of 29.6 percent.

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Plague: Rabies

Target: Bats, monkeys, dogs, raccoons, foxes…and a lot more

Rabies is present on all the continents of the world except Antarctica. The virus, transmitted through the saliva of an infected animal or person, travels through the nerves up to the brain, where it undoes an animal’s ability to regulate its own heartbeat, breathing, and salivation. Most victims die from respiratory failure or irregular heart rhythms.

In the U.S., vaccination drives for pets have caused the disease has to move from one primarily of domestic animals to one primarily found in wildlife, which represent 90 percent of all animal rabies cases reported to the CDC. Most mammals can contract rabies, but the primary source of human rabies transmission in the U.S. these days is bats, with raccoons and skunks the most frequently reported rabid animals.

To prevent the spread of rabies, health and wildlife departments in many Eastern U.S. states entice animals to consume oral rabies vaccine by concealing doses in a coating of dog food or fishmeal. The bait is deposited by hand in urban and suburban areas and dropped from planes in rural areas.

Plague: Chytridiomycosis

Target: Frogs

Around 200 amphibian species have declined or gone extinct thanks to this rapidly-spreading fungal disease. The chytrid fungus Batrachochytrium dendrobatidis infects the cells of a frog’s outer layer of skin, which they rely heavily on for respiration. The infected skin becomes thicker, impeding the frog’s ability to absorb water and electrolytes through its skin, and eventually leading to cardiac arrest.

Various treatments are being investigated for chytridiomycosis, including incubating tadpoles in warmer water that kills the fungus and bathing adult frogs in antifungal treatments. While these methods show promise, it is still possible for the frogs to get re-infected out in the wild.

Plague: Cattle fever

Target: Cows, deer

The U.S. government employs a cadre of cowboys to ride the banks of the Rio Grande in order to stop the spread of ticks that cause cattle fever. Parasites transmitted by the ticks can kill a cow within days of the first symptoms, or can cause a wasting disease that can last for weeks and cut a steer’s weight by 20 percent in just a year. A nationwide tick eradication program has largely pushed cattle fever out of U.S. borders, but the “tick rider” cowboys still patrol the borders to catch any stray Mexican cattle—often abandoned by ranchers fleeing drug war violence—that might spark an outbreak.

Wildlife are another possible source of cattle fever, as both white-tailed deer and the imported nilgai antelope can also carry the ticks. Climate change may make the southern U.S. an even more hospitable environment for the ticks, as well as the spread of invasive reeds that shelter the bugs. Scientists are working on ways to combat the reeds, the ticks, and the cattle fever parasite—including a wildlife vaccine distributed in biscuit form.

This article originally appeared on World Science Festival.

TIME China

Bubonic-Plague Death Triggers Quarantine of Chinese City

The 38-year-old victim may have come into contact with a dead marmot carrying infected fleas

Parts of a city in northwestern China are under quarantine after a local man died of bubonic plague, according to a state media report Tuesday.

A quarantine has been put in place for Yumen, a city of about 100,000 in Gansu province. No one but the original victim has shown signs of infection, Reuters reports.

The victim, 38, died July 16, apparently after coming into contact with a dead marmot, a rodent. Plague is a bacterial disease typically carried by fleas hosted by rodents. The disease is extremely deadly if not treated immediately.

Plague is very rare but still exists, primarily in rural areas. The Yumen quarantine comes after three new cases of bubonic plague were confirmed in the U.S. state of Colorado on Friday.

TIME plague

3 New Plague Cases Confirmed in Colorado

The state health department has found a total of four people infected with the pneumonic plague

Three new cases of plague have been identified in Colorado for a total so far of four, the state health department announced Friday.

The four people diagnosed all had contact with a dog that died of the plague. The initial patient remains hospitalized but the three infected later “all had minor symptoms, were treated with appropriate antibiotics, recovered and are no longer contagious,” the health department said in a release.

Plague is spread from rodent—in this case prairie dogs—to other animals, including humans, by rogue fleas.

Of the 60 cases of plague in its various forms that Colorado has seen in recent years, nine people have died from the disease, according to a Bloomberg report. Doctors recommend keeping a safe distance from any rodents, alive or dead.

TIME Archaeology

Relics of ‘End of World’ Plague Excavated in Egypt

The plague is believed to have claimed the lives of 5,000 people a day in Rome alone

A new archaeological discovery in Egypt includes traces of an ancient disease that some in the Roman Empire considered a harbinger of the apocalypse.

The discovery was made in Luxor by members of the Italian Archaeological Mission to Luxor, LiveScience reports. Researchers uncovered the remains of bodies covered with lime, presumably used to disinfect the diseased, as well as three kilns in which the lime was made. They also found human remains scattered throughout a site that bears traces of a bonfire —likely a place where many disease victims were incinerated.

An analysis of pottery remains in the kilns indicates that the findings date from the 3rd century A.D., when a vicious plague claimed the lives of thousands living in the Roman Empire, including at least two emperors. The epidemic, which Carthaginian bishop Cyprian wrote signaled the end of the world, struck around 250 A.D. It is now considered to have significantly contributed to the empire’s decline.

The disease has been dubbed “the plague of Cyprian,” as the bishop wrote extensively about its effects on the human body. The “intestines are shaken with a continual vomiting, [and] the eyes are on fire with the injected blood,” he wrote in Latin in his De mortalitate. Most modern-day scientists believe the deaths were caused by smallpox.

TIME health

The Medieval Black Death Made You Healthier—If You Survived

Plague killed millions in Europe
The Black Death killed as much as half of Europe's population Photo by Science & Society Picture Library/SSPL/Getty Images

The plague was horrific, could hit without warning and killed tens of millions in 14th century Europe. But paradoxically, the population that survived ended up better off, with higher wages, cleaner living conditions and healthier food

Game of Thrones doesn’t tell you the half of it. Life during the medieval ages was nasty, brutish and short. That was especially true during what became known as the Black Death. The widespread outbreak of plague struck between 1347 and 1351, killing tens of millions of people, resulting in the loss of 30 to 50% of the region’s population. The disease itself was horrific. “In men and women alive,” wrote the Italian poet Giovanni Boccaccio, “at the beginning of the malady, certain swellings, either on the groin or under the armpits…waxed to the bigness of a common apple, others to the size of an egg, some more and some less, and these the vulgar named plague-boils.” And it seemed to strike indiscriminately and without warning. People could be healthy in the morning and dead by evening.

The upside, if you can call it that, is that the plaque left in its wake populations that were healthier and more robust than people who existed before the plague struck, according to a new study published today in PLOS ONE. “The Black Death was a selective killer,” says Sharon DeWitte, a biological anthropologist at the University of South Carolina and the author of the paper. “And after the Black Death ended, there was actually an improvement in the standard of living.” The plague was natural selection in action.

In a way, that’s a marker of how brutal the medieval era was. It took a serial killer of a plague to actually bring about an improvement in living conditions. If that sounds counterintuitive, think about how life might have changed after half of Europe’s population died off. Suddenly there was a dramatic drop in the number of able-bodied adults available to do work, which meant survivors could charge more for their labor. At the same time, fewer people meant a decreased demand for foods, goods and housing—and as a result, the prices for all three dropped. By the late 15th century, real wages were three times higher than they were at the beginning of the 14th century, before the plague struck. Diets improved as employers were forced to raise wages and offer extra food and clothing to attract workers. As a result, the money spent per capita on food in the wake of the Black Death actually increased. “People were able to eat more meat and high-quality bread, which in turn would have improved health,” says DeWitte.

But the clearest evidence that people were healthier after the Black Death than they were before it comes in the bodies themselves. DeWitte looked at skeletal samples taken from medieval cemeteries in London both before the plague and after it. She found that post-Black Death samples had a higher proportion of older adults, and that morality risks were generally lower in the post-Black Death population than before the epidemic. In other words, if you were strong and lucky enough to survive one of the deadliest epidemics in human history, you were probably strong enough to live to a relatively ripe old age. And since the Black Death was so widespread, that was true for the surviving population as a whole.

Earlier studies looking at historical documents like diaries, letters and wills from the time period had shown conflicting results, but that kind of data only covers the very small part of the population that was literate, male and relatively well off. The advantage of DeWitte’s grave-combing bioarchaeological research methods is that they encompass a much more representative swath of the medieval population. “This provides information about the people who are missing from historical documents, including women and children,” says DeWitte. Not everyone in medieval London left a will behind—but everyone left a corpse.

So for survivors, life after the Black Death would have been at least a little less nasty, brutish and short than life before it. But that doesn’t mean the survivors were really the lucky ones. The Black Death was a period of unremitting horror and terror, the likes of which we can’t imagine. No one knew how the disease spread, or how to treat it. Popular but gruesome methods like blood-letting or boil-lancing would have been counterproductive at best, assuming victims could find anyone to treat them. Doctors abandoned their patients for fear of infection, and priests even refused to give last rites to the dying—an appalling dereliction given medieval fears of eternal damnation. Even animals like sheep, cows and pigs fell victim to the disease. “The people who survived the Black Death would have lost everyone they knew,” says DeWitte. “They’re the people I feel sorry for.” If the Black Death really was natural selection at work, it was the cruelest form imaginable.

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