Virus - Wikipedia
It can be a virus that is isolated from its natural reservoir or isolated as the result of spread to an animal or human host where the virus had not been identified before.

Virus | Definition, Structure, & Facts | Britannica
Virus, infectious agent of small size and simple composition that can multiply only in living cells of animals, plants, or bacteria. Viruses possess unique infective properties and thus often cause disease in host organisms. Learn about the history, types, and features of viruses.

Viruses: Definition, Types, Characteristics & Facts
A virus is a small piece of genetic information in a “carrying case” — a protective coating called a capsid. Viruses aren’t made up of cells, so they don’t have all the equipment that cells do to make more copies of themselves.

VirusTotal - Home
VirusTotal Assistant Bot offers a platform for users to interact with VirusTotal's threat intelligence suite and explore artifact-related information effectively.

Virus - National Human Genome Research Institute
A virus is an infectious microbe consisting of a segment of nucleic acid (either DNA or RNA) surrounded by a protein coat. A virus cannot replicate alone; instead, it must infect cells and use components of the host cell to make copies of itself.

VIRUS Definition & Meaning - Merriam-Webster
Examples of virus in a Sentence Is the illness caused by bacteria or a virus? I think I have the virus that's going around this winter. The software checks your hard drive for viruses.

Viruses - National Geographic Society
In humans, viruses can cause many diseases. For example, the flu is caused by the influenza virus. Typically, viruses cause an immune response in the host, and this kills the virus. However, some viruses are not successfully treated by the immune system, such as human immunodeficiency virus, or HIV.

What is a Virus? - News-Medical.net
A virus is a small infectious agent that can only replicate inside the cells of another organism.

Introduction to viruses - Wikipedia
When a virus infects a cell, the virus forces it to make thousands more viruses. It does this by making the cell copy the virus's DNA or RNA, making viral proteins, which all assemble to form new virus particles.

Viruses: What are they, and what do they do? - Medical News Today
After entering a host cell, a virus hijacks the cell by releasing its own genetic material and proteins into the host. It uses the host’s cellular machinery to make many copies of itself.