VIRUS Q & A

What is a virus?

A virus is a tiny (submicroscopic) infectious agent that reproduces inside the cells of living hosts. When infected, the host cell is forced to rapidly produce thousands of identical copies of the original virus. All viruses contain encoded biological information in genes built from either DNA or RNA with. All viruses are also covered with a protein coat to protect the genes.

Are viruses “alive”?

Unlike most living things, viruses are not made of cells that can reproduce by division; instead, new viruses need the infected host cell of an organism in order to replicate. Because viruses are non-cellular and cannot reproduce independently, many biologists do not consider them to be, by definition, "alive". Some biologists disagree and consider viruses to be living organisms because they do contain genes, which allow them to mutate and evolve.

How many species of viruses exist?

Approximately 7,000 species of viruses have been identified. However, virologists believe that many thousands more will be discovered over time.

Are all viruses dangerous to humans?

No. About 200 types of viruses can cause infectious diseases in humans.

Can viruses harm other organisms?

Viruses infect a wide variety of host organisms. They cause diseases in bacteria, fungi, plants, and animals.

What are some of the common viral diseases in humans?

Common cold, influenza, measles, mumps, rubella, chickenpox, shingles, rabies, HIV/AIDS, tetanus, polio, and of course Covid-19 are all viral diseases that can infect humans. Smallpox is the only viral disease that has been completely eradicated worldwide.

How can viral diseases in humans be prevented?

A vaccine is a biological preparation that provides active acquired immunity to a particular infectious disease. A vaccine typically contains an agent that resembles a disease-causing virus that stimulates the body's immune system to recognize a specific virus as a threat and then destroys it. Approximately 20 vaccines exist that produce at least partial immunity to specific viral diseases in humans. There are also vaccines for dogs, cats, horses, other livestock, and even wild animals. Plants and fungi can also immunized from some viral infections.

Antibiotics (such as penicillin) only work against bacterial infections; they cannot be used to prevent or treat viral infections.