Thank you for your question! Viruses can be killed in different ways depending on whether they are inside or outside the human body. Outside the human body, chemicals that we use to clean stuff (like alcohol or bleach) kill viruses. These chemicals are often made up of a combination of hydrogen, carbon, and oxygen but sometimes they contain other elements like nitrogen or chlorine, too. In our bodies, our immune system has special cells that can recognize viruses and kill them.

I hope this answers your question!