Study: Humans Give Animals More Diseases Than They Give Us

Apr 1, 2024

Do mother pigs scold their dirty piglets for being “filthy humans”? A new report suggests they have every right. Humans, after all, pass far more diseases to animals than they do to us.

Diseases can move from animals to humans. That's called zoonosis. It’s caused some of the deadliest diseases ever. The bubonic plague is one. It struck Europe in the Middle Ages. It was caused by bacteria. They passed from rodents to humans through lice. 

When a disease jumps from humans to animals it's called anthroponosis. It can be dangerous for animals. It is far more common, too.

Researchers looked at samples of 12 million viruses. They found nearly 3,000 kinds that moved from one species to another. Most, 79%, spread from animal to animal. The rest moved either from animals to humans, or vice versa. Animal-to-human cases made up 36% of those. The other 64% passed from humans into animals.

"This really highlights our enormous impact on the environment and the animals around us," Cedric Tan told Reuters. He is a biologist.

The COVID-19 pandemic led to anthroponosis. The CDC recorded dozens of cases. They include the disease passing to pet cats and dogs. Hamsters caught it from humans, too. So did exotic animals. Scientists found cases of human-to-animal COVID transmission in lions and otters. Hippos, manatees, and even a giant anteater also caught COVID from humans.

Reflect: What habits can humans adopt to make sure we’re not transferring diseases to animals?

Photo of cat from Reuters.

How does the fourth paragraph of the article support the main idea? (Common Core RI.5.2; RI.6.2)
a. It provides direct quotes from experts restating the main idea.
b. It provides evidence directly supporting the main idea.
c. It highlights controversies that distract from the main idea.
d. It explains a recent example of disease transfer that supports the main idea.
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