It’s amazing! Why these Canadian animals are so resistant to disease

Deer get sick, yes. But they don’t get sick with Lyme disease, despite the fact that they’re bitten by ticks carrying the bacteria that causes Lyme. Research from the New England Center of Excellence in Vector-Borne Diseases suggests that something in a deer’s blood kills the bacteria. If scientists can figure out what that something is, they could develop a drug that mimics the effects of whatever blood protein is responsible for keeping the deer healthy.

It’s a myth that sharks, such as Canada’s Greenland shark, are resistant to all disease. But they do have very strong immune systems. That makes sense: they’ve been alive for more than 400 million years. Research shows that their antibodies are practically indestructible compared to human antibodies. This is because those antibodies must survive in shark’s blood, which is incredibly high in salt—a hostile environment.

Holy immunity, Batman! Even though they carry all kinds of illness—more than 130 viruses, some of them deadly to humans—bats don’t seem to get sick from any of them. The reason? A bat has the distinction of being the world’s only flying mammal. And flying isn’t easy. Mid-flight, a bat’s body temperature soars to over 100°F, and its heart pounds at 1,000 beats per minute. If a bat’s body can withstand that stress, it follows that its immune system also doesn’t “overreact” to infection the way that ours does, and consequently, the bat doesn’t experience sickness the way that we do.

Not only do these big, scavenging birds have strong immune systems, their stomach acid is so caustic that they can safely consume rotting flesh or carcasses teeming with rabies, polio, tuberculosis, hepatitis, anthrax…pretty much anything. In fact, vultures in general have the lowest gastric pH of the animal world. Their insides are strong enough to dissolve metal, not to mention, kill almost any bacteria that they consume.

Okay, fine. They may get sick from disease, but they aren’t harmed by snake venom, it seems. These marsupials—including Canada’s Virginia (a.k.a. North American) opossum—appear immune to the effects of a bite from a venomous snake. Or, at least, nearly immune. Researchers have known since the 1940s that opossums are resistant to pit viper venom; more recent studies suggest that they could take as many as 80 snake bites before succumbing to venom. For the record: honey badgers, hedgehogs, mongooses, and pigs also appear to show venom resistance. Who knew?