"Well, the Shmoam-ag created themselves a nasty virus, near one hundred percent fatal."

He wants to become the nastiest new virus, attempting to kill each new victim faster than the previous.

It was a nasty virus, but Greg couldn't see an alternative.

"It is a nasty virus and can hit people pretty quick."

"And when we arrive, Petyr-san, will the nasty viruses somehow be gone?"

They don't carry any nasty zoonotic viruses, so far as we know.

No one wants to own a computer infected with a nasty virus.

I've just discovered he brought a nasty virus on board with him.

Jesus, you make it sound like I've got a nasty virus of a pesky little venereal disease.

Any day, without warning, the air may be filled with nasty viruses.