Bacteria and Viruses: How Are They Different?

When people are being cautious about getting sick, they will typically think of, and make every attempt to avoid, bacteria and viruses. That’s because both routinely play a role in making people of all ages mildly or extremely ill. Although people are familiar with general information about bacteria and viruses, such as the fact that they are both invisible to the naked eye, most do not fully understand what they are. It is important, however, that people of all ages have a better understanding of what their differences are. This includes knowing what these organisms can do and whether they serve any beneficial purpose.


Bacteria can be found both in living organisms and outside of them. They themselves are living organisms known as prokaryotes, or prokaryotic cells, which are single-celled organisms. Bacteria lack a nucleus and are typically found in large groups. They can be various shapes, including rod- or spiral-shaped, and some have a flagellum, which is a whip-like tail, that helps them move around. Although people tend to think of the bad aspects of bacteria, like the fact that they cause illness, they also fulfill many beneficial purposes in terms of human health and the environment. There are hundreds of different types of bacteria that live in and are good for the gut, for example. They help with digestion, can prevent gastrointestinal problems, and are good for the immune system. Bacteria in the large intestine even help make vitamin K. Good bacteria are also of benefit to the environment in a number of ways, including helping to make the soil more fertile.


A virus is a particle that lacks cellular structure. Viruses do, however, contain single- or double-strand nucleic acid and a protein coat or shell which encloses genetic material that is either DNA or RNA. It lives in and requires the cells of a living organism such as a human, animal, or plant. This living host enables it to replicate itself and to survive. Although they interact with living hosts, there is some dispute among the scientific community as to whether a virus is an actual living organism. Those who do see it as a life form consider it the simplest form of life that’s known to humanity. They are widely associated with illnesses and severe contagions.

Differences Between Bacteria and Viruses

There are a number of differences between bacteria and viruses. Viruses, for example, are as much as 10 to 100 times smaller than bacteria. Unlike viruses, which are frequently believed to be organic structures interacting with living organisms to survive and replicate, bacteria are actual living organisms that reproduce via a form of asexual reproduction called binary fission. While viruses have a protein coat but no cell wall or ribosomes, bacteria do have ribosomes present, and their rigid cell walls are made of peptidoglycan. While the RNA and DNA of viruses are enclosed in the protein coat, in bacteria, the genetic material floats in the cytoplasm. The cytoplasm is made up of enzymes, nutrients, wastes, and gases and is enclosed by the cell wall and cell membrane.

When it comes to benefits, viruses are typically non-beneficial; however, there is some use for them in genetic engineering, and research has been conducted that shows that a specific type of virus may be used to destroy tumors in the brain. Because both viruses and bacteria cause illness, it is important to understand their differences in this regard. In terms of infection bacterial infections are generally localized, while viruses are systemic. Conditions caused by bacteria can generally be treated with antibiotics, which will kill most forms of bacteria. Antibiotics cannot, however, kill viruses or aid in the treatment of a viral infection or illness. Anti-viral medication is often used to treat an illness that is due to viruses and can slow down its reproduction. Vaccines are helpful in preventing the spread of viral diseases.