Here Are All the Poop-Inducing Pathogens Carried by NYC's Rats

No one was under the illusion that New York's rats were clean creatures, but a study published this week in mBio found dozens of viruses that have never been described by science, some of which may be potentially harmful to humans.

"While a subset of the agents we identified are known to cause disease in humans, many more are novel viruses whose zoonotic potential cannot be inferred from available data," Cadhla Firth, the lead researcher of the team from Columbia University, wrote. "It is therefore possible that human infection with some of the agents identified here may already be occurring, and the risk of future zoonotic transmission should not be disregarded."

Beyond that, the researchers found many, many pathogens that are well known and are very bad for people, pets, and sometimes even zebras. So, in an attempt to scare the bejesus out of everyone, I quickly analyzed the 32 species of clinically important microbes that were identified. Here's what I found:

Bartonella spp.—Associated with Lyme disease-like symptoms in humans; bad for pets.

C. jejuni—common cause of food poisoning, Guillain-Barre syndrome

C. difficile—causes infectious diarrhea, kills 14,000 people a year in the United States. Treatable with frozen poop pills.

EPEC (atypical)—Enteropathogenic E. coli, described by the NIH as an "important cause of diarrhea."

L. interrogans—Causes leptospirosis, which is either asymptomatic or kills you due to liver damage and renal failure, and a disease common in Indian slums.

S. enterica—Salmonella, leading cause of food poisoning, meaning diarrhea and vomiting.

Shigella/EIEC—Causes dysentery.

S. moniliformis—Causes "rat bite fever," a "a systemic illness classically characterized by fever, rigors, and polyarthralgias (chronic pain and joint swelling)." Difficult to diagnose (getting bit by a rat is one clue that you may get it), and carries a 10 percent mortality rate if untreated.

Y. enterocolitica—Causes Yersiniosis, which is also known as "pseudo tuberculosis." Symptoms include diarrhea ("often bloody," says the CDC), abdominal pain and fever. Often clears up on its own.

SEOV (Seoul virus) Baxter—A type of hantavirus endemic to Asia, SEOV causes hemorrhagic fever and has a mortality rate of around 1 percent. As the authors of the latest paper note, the introduction of the SEOV Baxter variant "into NYC appears to be recent."

Anelloviridae—Recently discovered. Three genera are believed to be associated with illness; loosely linked to liver disease and acute respiratory diseases.

Bocavirus—Has higher incidence in people with cancer. Human bocavirus is associated with gastroenteritis and lower respiratory tract infections.

Mastadenovirus—Found in bats and rats.

Parvovirus—The type most often found in this study, Kilham rat virus, can occasionally cause disease in rats that can lead to fat loss and "scrotal hemorrhage." It's often a problem in "naive" research rats, as wild rats like those in NYC have developed stronger immunities.

Calhevirus—Very little information available about this one. Originally discovered in 2010.

Cardiovirus—Can cause multiple sclerosis-like symptoms in mice. A type of cardiovirus that infects humans was discovered in 2007, and is found in people with meningitis.

Circovirus—Bad for dogs.

Hunnivirus—Not a lot out there about this one. Found in cattle and sheep.

Mamastrovirus—Species in this genus show up in humans, cows, cats, minks, etc.

Rotavirus—Can cause gastroenteritis, vomiting, diarrhea, and so on.

Other—These included densoviruses, dependoviruses, dicistroviruses, nodaviruses, tobamoviruses, a variety of bacteriophage, and endogenous viral elements.

It's important to note here that every single virus found in the "novel" category is at least 70 percent different than its closest described relative. We have no idea what these do yet. Everything from here on out is based on each virus' closest relative.

Arterivirus—Causes a nasty fever, depression, conjunctivitis, miscarriages in horses. No known human danger.

Hepacivirus—A mutated form of rodent hepacivirus was found in these rats, which is fairly common. Unclear what it does.

Orbivirus—Causes African horse sickness, for which there is no treatment. Often infects zebras, horses, dogs, and causes respiratory and cardiac problems. Often kills its host.

Pegivirus—A new genus of virus described last year. Certain types infect humans but it's unknown whether it causes illness. Causes Theiler's disease, a horse-form of hepatitis that's one of the most common causes of liver failure in horses.

Pestivirus—Causes classical swine fever, in which the kidneys of wild boars, pigs, and peccaries stars bleeding profusely. They die within 15 days.

Hepeviridae-like—A never-before-seen virus in rats. This one is Hepatitis E in humans. You might know it—there are 20 million human Hep E infections worldwide, and it's transmitted through feces-infected drinking water. This particular strain found in rat feces, so that's comforting.

Kobuvirus—Kobuviruses have been associated with gastroenteritis in humans.

Parechovirus—Specifically, Ljungan virus (the species most closely related to the one found here) has been associated with diabetes and fetal death in humans.

Phlebovirus—This genus is home to the Heartland virus, which caused eight cases of Heartland virus disease in Missouri and Tennessee earlier this year. It's a new disease, and killed one person; the others had to be hospitalized with headaches, fever, fatigue, loss of appetite and diarrhea. To be clear, the Heartland virus is often associated with tick and mosquito bites, and the newly-discovered virus found in NYC rats is a different species.

Picobirnavirus—Associated with gastroenteritis in humans; never before seen in rats.

Pure nightmares.

Picornaviridae—This family is home to the virus that causes polio, as well as viruses responsible for hepatitis A and the common cold. The particular species found here infects cats and bats, however, so that's slightly reassuring.

Rosavirus—A brand new family of viruses that has just recently been described and is seen most often in rodents. Very little is known about it.

Sapovirus—Named after Sapporo, a wonderful brand of beer that makes impenetrable steel cans and city in Japan where there was a massive outbreak of gastroenteritis in an orphanage, which led to the first description of the virus.

C. parvum—This parasite is believed to have a role in causing anorexia, causes nausea and vomiting, abdominal pain, and lung problems. Has a high mortality rate in people with HIV/AIDS.

The very little good news here is that the rats were shockingly without Toxoplasma gondii, a parasite that controls rats' brains to make them more impulsive and thus, easier prey for cats. The virus is found in the roughly half of humans, and might be controlling your brain, too. So, those living in New York at least have that going for them. Hooray.