Virus vs Bacteria: Differences Between These Microscopic Entities

Viruses and bacteria are among the microscopic biological entities that can both be useful as well as harmful. Of the two, viruses are especially mind-boggling things. They lack almost everything to be counted among the living being. Nevertheless, viruses not only reproduce but they are, in fact, the most abundant bio-form on earth. Viruses are totally parasitic in nature. They hijack the cell machinery of the host to multiply. On the other hand, bacteria are single-celled living organisms that are capable of multiplying on their own without needing support from host. Likewise, there are a number of differences between virus and bacteria. Let’s have a look at these differences!

Virus vs Bacteria: Differences between Viruses and Bacteria

structural difference between virus and bacteria
Differences between Viruses and Bacteria
Characteristic Virus Bacteria
Life Viruses are considered non-living entities. Bacteria are living single-celled organisms.
Reproduction Viruses always need a host cell in order to multiply. Bacteria reproduce asexually through binary fission.
Cell Wall Cell wall is absent in viruses. Instead a protective protein coat called capsid is present. Cell wall made of lipopolysaccharide or Peptidoglycan is present.
Size Size of viruses varies between 20nm to 400nm. Viruses are visible only under electron microscope. Comparatively bacteria are much bigger with size ranging between 800nm to 1000nm. Bacteria can be seen under light microscope.
Ribosomes Absent in viruses. Ribosomes are present in bacteria.
Genetic material DNA or RNA remains encased inside capsid. DNA or RNA floats freely in cytoplasm.
Metabolism Viruses do not have any metabolic activities inside virus particles. Bacteria show metabolic activities inside cell.
Harmfulness Most viruses are harmful but some can be beneficial. Only a small percentage of bacteria causes harm to human beings.
Infection Viruses cause systemic infections. Bacteria cause localized infections.
Diseases Covid-19, AIDS, common cold, influenza, and chickenpox are examples of viral diseases. Gastritis, food poisoning, ulcers, meningitis, and pneumonia are common bacterial diseases.
Treatment Viral disease can only be prevented with vaccines. Bacterial infections can be cured with antibiotic drugs.
Examples SARS-CoV-1, SARS-CoV-2, HIV, Poliovirus, Nipah are examples of viruses. Staphylococcus aureus and Vibrio cholera are examples of bacteria.