The Ebola virus is a very infectious virus.

The poliovirus is a virus that primarily enters the body through the mouth and destroys the nervous system.

Norovirus can be prevented by hand washing and disinfection.

Do you understand the necessity of this project?

That information is unnecessary.

That information is completely unnecessary.

He thinks that war is a necessary evil.

Our lives have changed significantly due to the impact of the coronavirus.

In the midst of the corona disaster, we learned a new lifestyle.

Due to the impact of the Wuhan virus, the whole world is in a difficult situation.