Virus

What is a Virus?

A virus is a tiny living thing that can only grow by taking over the cells of another organism. Viruses can infect animals, plants, bacteria, and other tiny organisms. They are found almost everywhere on Earth and are very common.

Viruses are so small that you need special tools to see them. When a virus gets inside a cell, it uses that cell to make many copies of itself. Outside of a cell, a virus looks like a small particle made of genetic material wrapped in a protein coat.

How Do Viruses Spread?

Viruses spread in many ways. Some are carried by insects like aphids that feed on plant sap. Others move through the air when people cough or sneeze. Foods and water can also carry viruses. Our bodies usually fight off viruses with an immune response. Vaccines can help prepare our immune systems to protect us better.

The Word "Virus"

The word "virus" comes from an old Latin word meaning "poison." Long ago, people used this word to describe harmful liquids. Now, we know that viruses are tiny things that can make us sick.

Viruses have been around almost as long as life itself. They probably existed when the first living cells appeared. Scientists use special methods to study their history.