MINNEAPOLIS (WCCO) — Fear of the coronavirus has spread around the world, but this is hardly the first time there have been new, deadly infections.

So Roger from Hudson wanted to know: How does a virus start? Good Question.

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From West Nile to swine flu to the common cold to measles to SARS to HIV to Ebola, the NIH says there are more than 200 viruses that can affect humans.

There are hundreds of thousands, though, that can live in other kinds of animals.

A virus is made up of genetic material and can only live inside the cells of a living host, like a human or an animal.

“Whatever that cell was intended to do, the virus takes it over and says, nope, you’re not going to make more cells, you’re going to make more viruses,” says Kris Ehresmann, head of infectious diseases at the Minnesota Department of Health.

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Often times, viruses found in humans start in animals. The 2019 Novel Coronavirus has been called “new” because it’s new to humans.

“That virus jumped from animals to humans and then modified itself so it could cause illness in humans,” Ehresmann says. “What makes this virus unique is that this virus has not only affected people but modified itself so that it can spread between people.”

How the virus moves from animals to humans depends on the virus. Experts believe MERS stared in camels, SARS in civet cats, and swine flu in pigs.

Viruses can make the jump anywhere, it’s scientists say it’s more likely happen in places with more human/animal contact.

“Really any culture that has live animal markets is because there’s more opportunities for humans and animals to interact on a regular basis,” says Ehresmann. “We see that less here because we don’t interact with animals at nearly the same level as other parts of the world.”

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Companies are working on a vaccine for the coronavirus now. So far, the only virus humans have eradicated is smallpox, which happened primarily through vaccines.

Heather Brown