Viruses are tiny particles found in the cells of living plants and animals that can only be seen with electron microscopes. They feed on these living cells and multiply extremely rapidly. Some are harmless, but many are the cause of serious illnesses like AIDS. The nucleus of viruses contains a form of nucleic acid, either DNA or RNA, this distinguishes them from bacteria and other pathogens in which both are found.
What is virus
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According to biology, a virus is an infectious and microscopic acellular agent that reproduces and multiplies only through the cells of other organisms. Each basil that exists is made up of genetic material and, by infecting one or more cells of the nervous system, they cause each host cell to produce many, many copies of the bacteria.
These agents have the ability to infect any type of existing organism, that is, humans are not the only beings susceptible to contracting a virus, but both animals and plants also run the same risk.
Basils do not have enough cellular constituents that allow them to live without the need for it to be through others, that is why they live as tiny parasites in different cells, since a specific cell is needed for the microbe (depending on which) can inhabit it. This is known from the types of tissues that viruses tend to attack, for example, those that affect the skin are called dermatropic, also those infectious agents that affect the lungs are called pneumotropic.
There are also those that affect the nervous system and are called neurotropic (they are those that cause high fever and, consequently, weaken the nervous system, affecting respiration, the heart system and multiple organs.
On many websites they claim to call any disease that can affect the nervous system zombie virus, but there is nothing like this type of pathology presented in cinematographies).
Finally, there are those infectious agents that affect the viscera and internal organs, these are called viscerotropic (an example of this, are stomach diseases that are contracted through viruses and bacteria). The basils that remain active, manage to enter and remain in the cells, become the owners of cell reproduction and end up multiplying the infectious agent.
Generally, cells are destroyed in this process, which is repeated many times. Once inside the body, some settle and live inactively for long periods of time, possibly years.
Others manage to multiply in limited quantities with the sole function of causing symptoms. Viruses and bacteria tend to be transmitted in different ways, some can be through fluids such as saliva, others through the air, bites or by consuming contaminated food and water.
Currently, most virus-type diseases are prevented and eradicated with vaccines that stimulate the production of antibodies in the body. There is a vaccine for each basil, but unfortunately they have not created vaccines for the most recent ones.
History of viruses
These agents were considered biologically infectious in the early nineteenth century, however, there are texts from ancient Mesopotamia (1800 BC) and Egyptian hieroglyphics that depict some cases of diseases similar to those produced by germs, for example, polio and disease. of rage.
In the 1st century BC, Cornelius Aulus Celsius used this word for the first time, referring to the term as a poisonous agent (and explained that rabies was transmitted by poisonous saliva).
Many scientists investigated various diseases caused by tiny organisms that damaged cells, but it was not until the middle of the 20th century that viruses were assumed to be biological agents that multiplied in cells. In fact, it was the golden age, as they discovered more than 200 viruses of animal origin and others that are transmitted in the environment.
Characteristics of viruses
In terms of morphology, they are totally different from each other, however, there is something that unites them all and that is their size. These are, in scale, quite tiny compared to bacteria.
The characteristics of these bacteria are described according to their structure and their genome.
Structure
Small infectious agents are simple, they are made up of nucleic acid nutrients (there is no other agent that can make them up). This acid is a viral genome and is located inside the particle, and can be RNA or DNA. These structures can be icosahedral helical, envelope or complex.
- Helical: it has a helix-like shape, a central hollow cavity and it is there where the genetic material of the basil is located regardless of whether it is DNA or RNA)
- Icosahedral: they are symmetrical, they are almost spherical and they are the most common to infect animals.
- Envelope: they are so called because they have a lipid envelope that manages to extract the cell membrane of its new home. This membrane also acts to introduce its own genetic material into the infected cell.
- Complex: they tend to be half helical, have extra structures such as a kind of tail full of proteins (the same that introduce their genetic material into the cell), and even have an icosahedral shape
Genome (DNA: RNA)
It is the genetic material existing in each microbe, which can be reproduced, becoming virulence and then a viral strain.
- Reproduction: it is nothing more than the reproductive cycle of viruses and, in order to establish it, it is necessary to understand the fixation and entry into the cell, its multiplication and proliferation of the basil (as explained previously). It must be remembered that these agents are acellular and cannot reproduce or multiply unless they are as a host in a foreign cell, that is, they are parasites.
- Virulence: refers to the harmful and pathogenic nature of a basil, bacterium or fungus that determines its virulence. This means that virulence is associated with the level of pathogenicity or the ability to generate damage of a microorganism.
It is important to note that the virulence of a deadly pathogen is easy to measure, however the virulence of those pathogens with non-harmful effects are much more complex to assess, as is the case with resistance to antibiotics. The resistance of these microorganisms to antibiotics is what determines their greater or lesser virulence.
- When virulence manages to be stopped, it will be speaking of organisms that have been weakened; vaccination being one of the elements associated with the nullification of virulence. Another interesting fact is that the virulence of a pathogen can change, depending on the host, which can cause a genus of bacteria to be harmful to all vertebrates.
- Viral strain: it is a group of bacteria that have a series of characteristics that individualize them, for example, the action and effect of the viral strain can be indicated with HIV disease. This disease has the ability to mutate its characteristics, giving rise to a new strain, which makes it possible for the effects that medicines have on the disease to be very minimal or, in the worst case, null. This means that there is resistance to the drugs and it tends to become quite aggressive.
Diseases caused by viruses
There are really too many diseases in the human species generated by a basil, some are infections that last for a few periods of time, but there are also those that last and that can only be eradicated with treatment. Some of the most common diseases generated by these infectious agents are Zika virus, measles virus and dengue virus, which in addition to affecting the body internally, also left dermal damage. There is also the anthrax virus, which enters the body by breathing spores, the influenza virus and piv viruses, which directly affect the throat and lungs.
Form of contagion
Transmission is relative and depends on the type of agent being discussed, as some tend to be transmitted from one individual to another through fluids, either through sexual intercourse, coughing, sneezing, blood transfusions and direct contact with the skin of a woman. infected person. It can even be transmitted by a mosquito, the bite of any animal or the consumption of contaminated food.
Prevention
In the first place, a high level of hygiene must be maintained to avoid the virus, mouth, hand, feet, which must be kept clean at all times, wash food well, avoid excessive contact with people and have vaccines for infectious agents more common. If there is a suspicion that you are suffering from a virus, it is advisable to go to a doctor and follow all the recommendations that he can give you.
Vaccinations
Vaccines make the body immune to the effects of basil. Since the discovery of some infectious agents in the 20th century, many scientists began with the creation of vaccines that could confront and eradicate these viruses. These are extremely effective, they have some side effects but nothing alarming.
Viral Epidemics and Pandemics
These agents of infection have been in the earth for many centuries, affecting human and animal life in different ways. The epidemics and pandemics that have been suffered and that have been documented, range from rabies, smallpox, measles, poliomyelitis, AIDS, influenza, yellow fever, dengue, Zika, chikungunya, hepatitis, the black plague and, currently, the Coronavirus pandemic type Covid-19.
Examples of viruses
As mentioned before, mankind has gone through many infectious diseases at different times. In this section, some of the most influential will be named, along with their characteristics, origin and transmission.
Lymphotropic T virus
This is a type of infection that affects the T cells (type of white blood cells) which can cause the individual leukemia (it is a group of malignant diseases of the bone marrow that causes an uncontrolled increase of leukocytes in it) and lymphoma (cancer starting in lymphatic tissue).
This infectious agent can be spread by sharing syringes or needles, by blood transfusions or by sexual contacts, also from mother to children at birth or during breastfeeding. It is also known as human T-cell leukemia virus type 1 and HTLV-1.
Retrovirus
In the medical context, retroviruses are a type of basil belonging to the family of retroviridae. They are characterized by having genes encoded in RNA instead of DNA; in addition to having few molecules and having an immense capacity for mutation.
These promote the immune system to get out of control and begin to attack the body. It is important to note that once a person is infected, they must carry the virus for the rest of their life. Treatment for these people is based on controlling the symptoms, since so far there is no known cure.
Adenovirus
It is a group of infectious agents that affect the membranes, that is, the lining tissues. Some of the most famous adenovirus infections with flu, conjunctivitis, pneumonia, diarrhea and pneumonia.
Arenavirus
Arenavirus is a group or family of viruses whose members are generally associated with diseases transmitted by rodents in humans. Each microbe is normally related to a particular rodent host species in which it is kept.
Arenavirus infections are relatively common in humans in some areas of the world and can cause serious illness; It is estimated that around eight arenaviruses are known to cause human disease.
These agents comprise a certain number of RNA viruses that in 1970 were separated from the group of so-called arboviruses. It should be noted that each structural unit of arenavirus encompasses a seeding of tiny grains resembling grains of sand.
Parvovirus
This is the common term that is applied to the group of viruses of the taxonomic family called "Parvovirids"; These basils are linear single-stranded, non-DNA segmented, characterized with an average genome size of 5,000 nucleotides; parvoviruses are some of the smallest infectious agents around 18-28 nm in diameter.
These basils can cause disease in some animals, since they require actively dividing cells to duplicate themselves and the type of infected tissue varies with the age of the animal.
Arbovirus
This term is used to refer to a series of microbes that are transmitted by arthropod vectors; Its name comes from the English "Arthropod-Borne Virus", which literally means "virus transmitted by arthropods" which is contracted to give rise to the word arbovirus as such.
In this case, the transmitting agents are insects called arthropods that spread basil by biting a person or animal, then allowing it to enter the circulatory system of the infected individual. Symptoms of arbovirus infection generally occur 3 to 15 days after exposure to the infectious agent and last 3 to 4 days.
Enterovirus
They are a group of microbes that affect the intestines causing certain conditions; Generally, the individual who suffers from it presents a series of symptoms such as feverish symptoms, colds, being also associated with a gastroenteritis picture along with constant diarrhea, abdominal pain or cramps in addition to vomiting.
These infection agents are included within the Picornaviridae family, which is made up of four genera, of which two of them only affect animals, they are called "Cardiovirus" and "Aphthovirus"; the others greatly affect human beings, these are, the Rhinovirus and the Enterovirus.
Coronavirus
It is also known as the China virus. It is a fairly extensive family of basil that can affect both humans and animals. In the case of the affection to humans, several of these infection agents directly affect the respiratory system, thus generating different types of colds.
They may also cause more serious illnesses like MERS (Middle East Coronavirus Respiratory Syndrome). One of the coronaviruses that has recently been discovered is Covid-19, which has been declared a global pandemic by the world health organization.
Computer virus
In the field of computing there is software known as a computer virus, this is a program that executes itself and spreads by inserting copies of itself into another program or document for malicious purposes.
It has the ability to invade vital parts of the computer such as hard disk or ROM memory, altering the operation or startup of the computer and, what is more serious, affects programs by altering their execution, or attacking files, destroying them, thus losing information stored.
This software is associated with a program or file so that it can spread, infecting computers as it travels from one pc to another. It can be transmitted by removable storage media such as CDs, pen drives, etc., as well as in e-mails, on MSN, or web pages. The best way to combat it is to have a good antivirus installed on the computer and file filters. One of the malicious programs that can be prevented (and it is on phones) is the vtr virus.
History
In 1949 the first computer work was done by John von Neumann, who spoke about the theory of self-replicating computer programs and fully described how a computer program can be designed to reproduce and copy itself. Von Neumann created a computer program that could copy itself and was, in fact, considered the first computer virus in the world.
Later, Doug McIlroy, Robert Morris Sr., and Victor Vysottsky created a game that could render all of your copies unusable and even overwrite.
characteristics
Among the existing characteristics in these computer programs, there is the total loss of productivity, some cuts in the information systems, damage at the data level, it also has a high possibility of spreading through replicas and copies of files.
Currently, all this is quite common in the different social networks because they do not have an adequate security system. Another of the fixed characteristics of these programs is the loss of data and information.
Types
There are different types of malicious software on the web, including:
- The Trojan virus, which steals information from the hardware system, the recycler, which acts automatically to spread from one disk to another (USB to PC).
- The logic bombs are programs that are activated in a specific time, that is why they are called time bombs. The worms duplicate themselves.
- There are also hoaxes, which are not viruses but do transmit false messages that make the user make copies and forward them to their contacts without the user noticing.
- Finally, the Joke are not viruses, but they proliferate on the web in pages that mark errors.
Prevention
The best thing that can be done is to install an antivirus system on the different computer devices, in this way, not only does one of these software prevent infecting the system, but it also keeps the computer clean (computerized) and monitored.
