What is a virus?

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  1. Virus
    1. Definition of Virus
    2. Treatment for viruses
    3. How are the viruses composed?
    4. The shape of a virus?
    5. Microbiology and Viruses
    6. What are RNA viruses?
    7. Reproduction of a virus
    8. What is virology?
    9. Differences between viruses and bacteria
    10. It may interest you :


A virus is a microscopic agent, carrier of an infection, that can only multiply within the cells of other organisms and that is the cause of an endless number of diseases.


A virus is a word of Latin origin, whose meaning is poison or toxin. It is a biological entity that has the capacity to self-replicate when using cellular machinery.

Viruses swarm throughout our planet and are also the largest type of organism.

Definition of Virus

It is a microscopic infectious biological entity, much smaller than the cells it infects. In order to reproduce, the viruses penetrate the cells, insert their DNA or RNA inside the cell and use their synthesis structures to make copies of the virus. Influenza, colds, measles and chicken pox are some of the viral diseases.

The virus is an obligate intracellular parasite, of small size, consisting of nucleic acid and protein, which is the cause of numerous diseases such as: flu, Ebola, human papilloma virus, AIDS (HIV), among others. The word virus comes from the Latin "virus" which means "toxin" or "poison".

Treatment for viruses

Viruses are not bacteria and therefore antibiotics are not good for fighting a viral disease. Consult your doctor and avoid self-medication.

How are the viruses composed?

They are composed of a genetic material, which has the corresponding hereditary information, either DNA or RNA, a protein cover that has the mission to protect these acids and in some special cases, there may be a lipid bilayer that protects them when they are outside the cell.

It should be noted that viruses reach all organisms such as humans, animals, plants and are so small that they should be viewed from optical elements such as the microscope.

Specifically, we can establish that when classifying viruses we can make two large groups.

Thus, on the one hand, we would have the so-called DNA viruses that are identified by the fact that they take as a stage of their development what is the nucleus of the cell in question.

Within this category, there are also two classes: the single-stranded, in which a single-stranded DNA takes the lead, and the double-stranded, which in its case has double-stranded DNA.

The shape of a virus?

Regarding their shape, there are helicoids or icosahedra. The former are characterized by their curved lines and with a tangent that forms a constant angle and the latter are polyhedrons composed of twenty faces.

Its origin is subject to a variety of hypotheses, could have evolved from DNA fragments or bacteria, among the most mentioned.

The spread of viruses occurs in various ways, and even, each type of virus has a particular mode of transmission.

For example, transmission vectors are organisms that transmit viruses between carriers, while plant viruses are usually transmitted from insects when they feed through the sap.

For its part, the popular flu virus is transmitted from the air we breathe when people who hold it sneeze, cough, among others.

Microbiology and Viruses

Virology is the branch within microbiology that deals with the detailed study of viruses. The structure, evolution, classification, reproduction, the way they infect, the interaction with a host organism, the immunity they have, the diseases they trigger are some of the issues addressed by this discipline.

What are RNA viruses?

They are named for the reason that they use RNA (ribonucleic acid) as genetic material and also because they take the cytoplasm as a place to proceed to replication.

Within this modality, there are four groups: the positive single-strand, the single-transcribed retro-strand, the double-strand and the negative single-strand.

The life cycle of the virus, a potentially pathogenic agent, requires the metabolic machinery of the invaded cell, in order to replicate its genetic material and produce many copies of the original virus.

This process can harm the cell to destroy it.

Reproduction of a virus

Viruses need host cells to reproduce, within the cells can obtain amino acids, ribosomes and other substances that allow the multiplication of new viruses, once the virus is inside the cell begin to hinder the normal functioning of these causing named diseases previously, among many others.

The process of viral replication can take hours or days, everything depends on the virus.

In reference to the above, medical studies indicate that vaccines and antivirals are measures to deal with viral diseases and resist infection.

What is virology?

It is the branch of microbiology or medicine that is responsible for studying the behavior of viruses, their structure, classification, evolution, techniques for their isolation, among others.

Also, the generic name of diseases caused by pathogenic viruses is virosis.

Differences between viruses and bacteria

Sometimes, individuals use the terms virus and bacteria as synonyms, which is normal since these microorganisms similarly cause diseases, however, have different characteristics.

Viruses are acellular organisms, that is, they do not have cells, and to reproduce they need to inhabit the host cells.

These have a size of 20 to 500 millimeters of a diameter which can be detected by electron microscopy.

Likewise, bacteria are unicellular microorganisms, therefore, they are living beings that own cells.

These have a diameter between 0.6 and 1 micrometer. That is, they are up to 100 times larger than viruses so that it can be seen by optical microscopy.

Viruses have a simple structure consisting only of the genome, covered by a protein coat and viral capsid.

That is why they do not breathe, move or grow, instead, bacteria have a real cell wall, an internal structure and within this wall are the cytoplasm, the ribosomes and the bacterial genome, structure that allows them to grow and reproduce.

With respect to the cure, the viruses, as previously mentioned, are based on preventive and antiviral vaccines, the bacteria through the taking or injection of antibiotics.

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