Difference Between Virus and Bacteria

What is Virus?

A virus is a harmful microbe composed of a specific nucleic acid with a protein covering the outside of it. A virus attaches itself to a living organism and uses its cells to multiply itself in a harmful way. During the replication process, the virus damages the cells of its host organism and, in most cases, destroys them. Mostly, the replication is so dangerous that it kills the host.

As for the origin of viruses, there is no straightforward scientific explanation. Some scientists think that they originated from the elements that made their way into the cells or from the previously existing microorganism that developed into a toxic nature. The structure of a virus may be simple or complex. Generally, it has a protein or nucleic acid coated by the capsid.

It is untrue that viruses cannot be helpful in any way. In fact, they contribute to the greater scheme of life and evolution. Some particular types of viruses necessitated the emergence of living organisms on the face of the Earth. They also provide helpful insight to researchers to further their understanding of their scientific domains as well as to prevent these viruses from affecting human beings at large. Some of the most familiar examples of viruses are COVID-19 and AIDS

What is Bacteria?

Bacteria is the simplest existing microorganism in terms of structure. The functioning of bacteria is controlled by the center, which is made up of DNA. It contains a specific form of genetic material called a plasmid. The plasmid is composed of different genes that specify the distinctive quality of each bacteria. If a bacterium is resistant to an externally infused antibiotic, it is because of the genes in the plasmid. They can occur in spiral, comma, spherical, rod, and corkscrew shapes.

Bacteria can commonly occur in nature and are found almost everywhere on the Earth’s surface, from soils to oceans. Even in the human body, the number of bacteria is ten times double that the human cells. In everyday life, bacteria are also used in the fermentation process, especially in making yogurt. Bacteria are generally beneficial microorganisms, with a few exceptions that are detrimental to a living organism.

Since bacteria are present in the hierarchy of living things, they can reproduce as well. This unique process of bacteria reproduction is termed binary fusion. The reproduction starts with the bacterial DNA splitting into two – a single cell, hence, creates two daughter cells. Bacteria is speedily procreative and form millions of copies in a few hours. Some examples of bacteria are Listeria monocytogenes, Pseudomonas maltophilia, and Thiobacillus novellus.

Difference Between Virus and Bacteria

  1. Viruses are not considered living organisms, whereas bacteria are considered in the list of living organisms.
  2. Viruses are smaller in size and cannot be easily seen, whereas bacteria are comparatively larger in size.
  3. Viral diseases permeate the whole body, whereas bacterial diseases are confined to one part of the body.
  4. Viruses require host cells to multiply, whereas bacteria can independently reproduce in certain conditions.
  5. Viruses are mostly harmful to human beings, whereas not all bacteria are detrimental to the human body.

 Comparison Table Between Virus and Bacteria

Parameters of ComparisonVirusBacteria
NatureNot considered living organismsConsidered living by science
Scope of HarmWhole BodyA Specific Part of the Body
Reproductive Conditions(s)Host CellsIndependent Procreation
HarmfulnessMostly HarmfulNot Generally Harmful


  1. https://www.sciencedirect.com/science/article/pii/S0966842X05001083
  2. https://www.cabdirect.org/cabdirect/abstract/19662200831