Examples of viral diseases. Viral content to drive traffic from social media. Antibiotics for viral infection

Viruses (biology deciphers the meaning of this term as follows) are extracellular agents that can only be reproduced with the help of living cells. Moreover, they are capable of infecting not only people, plants and animals, but also bacteria. Bacterial viruses are usually called bacteriophages. Not so long ago, species were discovered that infect each other. They are called "satellite viruses".

General characteristics

Viruses are a very numerous biological form, as they exist in every ecosystem on planet Earth. They are studied by such a science as virology - a section of microbiology.

Each viral particle has several components:

Genetic data (RNA or DNA);

Capsid (protein shell) - has a protective function;

Viruses have a fairly diverse form, ranging from the simplest spiral to icosahedral. Standard sizes make up about one-hundredth the size of a small bacteria. However, most of the specimens are so small that they cannot even be seen under a light microscope.

They spread in several ways: viruses that live in plants are moved by insects that feed on herbal juices; animal viruses are carried by blood-sucking insects. U are transmitted in many ways: by airborne droplets or sexually, as well as through blood transfusion.

Origin

In our time, there are three hypotheses for the origin of viruses.

Briefly about viruses (on the biology of these organisms, our knowledge base, unfortunately, is far from perfect) you can read in this article. Each of the theories listed above has its drawbacks and unproven hypotheses.

Viruses as a form of life

There are two definitions of the life form of viruses. According to the first, extracellular agents are a complex of organic molecules. The second definition says that viruses are a special form of life.

Viruses (biology implies the emergence of many new types of viruses) are characterized as organisms on the border of the living. They are similar to living cells in that they have their own unique set of genes and evolve based on the method of natural selection. They can also multiply, creating their own copies. Since viruses are not scientists, they do not consider them as living matter.

To synthesize their own molecules, extracellular agents need a host cell. The lack of their own metabolism does not allow them to reproduce without assistance.

Baltimore classification of viruses

What viruses are, biology describes in sufficient detail. David Baltimore (Nobel laureate) developed his own classification of viruses, which is still successful today. This classification is based on the way mRNA is formed.

Viruses must generate mRNA from their own genomes. This process is necessary for the replication of its own nucleic acid and the formation of proteins.

The classification of viruses (biology takes into account their origin), according to Baltimore, is as follows:

Viruses with double-stranded DNA without RNA stage. These include mimiviruses and herpeviruses.

Single-stranded DNA with positive polarity (parvoviruses).

Double-headed RNA (rotaviruses).

Single-stranded RNA of positive polarity. Representatives: flaviviruses, picornaviruses.

Single-stranded RNA molecule of double or negative polarity. Examples: filoviruses, orthomyxoviruses.

Single-stranded positive RNA, as well as the presence of DNA synthesis on the RNA template (HIV).

Double-stranded DNA, and the presence of DNA synthesis on an RNA template (hepatitis B).

Life Span

Examples of viruses in biology are found almost at every step. But for all, the life cycle is almost the same. Without a cellular structure, they cannot reproduce by the method of division. Therefore, they use materials that are inside the cell of their host. Thus, they reproduce a large number of copies of themselves.

The cycle of a virus consists of several stages, which are overlapping.

At the first stage, the virus attaches itself, that is, forms a specific bond between its proteins and the receptors of the host cell. Next, you need to penetrate into the cell itself and transfer your genetic material to it. Some species also carry proteins. Thereafter, the capsid is lost and the genomic nucleic acid is released.

Human diseases

Each virus has a specific mechanism of action on its host. This process involves lysis of cells, which leads to their death. When a large number of cells die off, the whole body begins to function poorly. In many cases, viruses may not be harmful to human health. In medicine, this is called latency. An example of such a virus is herpes. Some latent species can be beneficial. Sometimes their presence triggers an immune response against bacterial pathogens.

Some infections can be chronic or lifelong. That is, the virus develops despite the protective functions of the body.

Epidemics

Horizontal transmission is the most common type of virus spread among humanity.

The rate of transmission of the virus depends on several factors: population density, the number of people with poor immunity, as well as the quality of medicine and weather conditions.

Body protection

The types of viruses in biology that can affect human health are innumerable. The very first defense reaction is innate immunity. It consists of special mechanisms that provide non-specific protection. This type of immunity is not able to provide reliable and long-term protection.

When vertebrates develop acquired immunity, special antibodies are produced that attach to the virus and make it safe.

However, acquired immunity is far from being formed against all existing viruses. For example, HIV constantly changes its amino acid sequence, so it leaves the immune system.

Treatment and prevention

Viruses in biology are a very common phenomenon, so scientists have developed special vaccines containing "killer substances" for the viruses themselves. The most common and effective method of struggle is vaccination, which creates immunity to infections, as well as antiviral drugs, which are able to selectively inhibit the replication of viruses.

Biology describes viruses and bacteria mainly as harmful inhabitants of the human body. Currently, with the help of vaccination, it is possible to overcome more than thirty viruses that have settled in the human body, and even more in the body of animals.

Prevention measures against viral diseases should be carried out on time and efficiently. For this, humanity must lead a healthy lifestyle and try by all possible ways improve immunity. The state, on the other hand, must arrange quarantines on time and provide good medical care.

Plant viruses

Artificial viruses

The ability to create viruses under artificial conditions can have many consequences. The virus cannot completely die out as long as there are bodies sensitive to it.

Viruses are weapons

Viruses and the biosphere

At the moment, extracellular agents can boast of the largest number of individuals and species living on planet Earth. They perform an important function by regulating the population size of living organisms. Very often they form symbiosis with animals. For example, the venom of some wasps contains components of viral origin. However, their main role in the existence of the biosphere is life in the sea and ocean.

There are approximately a million viruses in one teaspoon of sea salt. Their main purpose is to regulate life in aquatic ecosystems. Most of them are absolutely harmless to flora and fauna.

But that's not all positive traits... Viruses regulate the process of photosynthesis, therefore they increase the percentage of oxygen in the atmosphere.

Methods for combating viral diseases.

Diagnostics of viral diseases.

Methods of transmission of viral diseases.

1. When plant propagation inoculation, on the stock. It is important that the queen cells are free of viruses.

2. Contact contamination... As a result of leaf contacts, for example, through breakage of hairs (trichomes) during friction of leaves, through processing tools, garden tools, workers' clothes, especially when pinching, cutting flowers. (tulip variegation virus).

3. Vector transmission... The most common way. Viruses can be transmitted by insects, nematodes, fungi. Most of the carriers of gray aphids, leafhoppers, thrips, whiteflies. (potato virus, mosaic virus of cucumber, pea, beet)

The symptoms of viral diseases can vary greatly depending on a wide variety of conditions, so diagnosing viral diseases can be difficult.

1. Visual inspection. Fastest but least accurate method.

2. Serological method.If a virus is introduced into the blood of an animal, then specific proteins are formed in the blood serum - antibodies to this virus, which translate it into a harmless state. To diagnose a disease, a drop of the juice of the affected plant is mixed with a drop of diagnostic serum from the blood of an animal previously treated known virus... If the juice contains given virus, then as a result of the reaction of the virus and antibodies in the mixture, a flocculent sediment is formed, by the intensity of the precipitation of which one can judge the relative amount of the virus in the plant sap.

3. Indication method. Based on the infection of the indicator plant with the juice of the test plant. Indicators respond with definite clear symptoms to infection with a given virus. This is more sensitive, but also more time consuming.

4. Inclusion analysis method... With a razor blade, a section of the epidermis with leafy hairs is cut off and under a microscope they look for viral inclusions in the hair cells.

1. Destruction of diseased plants.

2. Use only healthy planting material.

3. Fight against insects - carriers of viruses.

4. Improvement of plants by the meristem culture method.

5. Disinfection of planting material by thermotherapy.

On garden carnation about 9 viral diseases were noted:

Bushiness virus.A sharp shortening of internodes is noted, dormant buds start to grow, forming many lateral shoots, plants do not bloom.

Soft mosaic virus. There are slight mottling on the leaves, light streaks on the flowers.

Ring spot virus.Chlorotic concentric rings on the leaves

Clove banded virus. Whitish, yellow, brown stripes or streaks on the leaves.

Many species of aphids and nematodes carry these viruses.

Yellow dwarf virus luke. Allium virus 1. There are short yellow stripes at the base of the leaves and on the flower arrows. The leaves turn yellow, the arrows are curved. The flower heads become smaller, the bulbs are small, the plants have a dwarf appearance.

On apple trees several types of viruses have been noted:

Apple Mosaic Virus.On the leaves there is a light mosaic in the form of small irregular cream or yellow spots. In summer, at the site of the spots - necrosis. Deformation of the leaf blade is sometimes observed.

Rosette virus.Rosettes of very small ugly leaves are formed on the shoots.

Branch wilting virus. The plant has a "weeping" appearance. The shoots droop, the wood in them is soft due to the absence of lignification processes. The turgor in the cells is reduced, there is a lag in growth.

Paniculate or bushiness virus.On individual branches, numerous shoots are overdeveloped.

Fruit cracking virus.The flowering is belated, there are few flowers, the fruits are single, the affected shoots die off. On the fruits - stellate cracks around the calyx.

Asters ringed spot virus.It causes the formation of chlorotic rings and zigzag lines on the leaves of asters - Chinese callistephus, zinnia, perennial aster.

Viral content - This is information that spreads over the Internet at a progressive rate through transmission from user to user (on the principle of "word of mouth"). This is content created using viral marketing techniques and consisting of bright, extraordinary, urgent, emotional, interesting and attention-grabbing materials that voluntarily the audience shares.

The distribution of viral content involves the recipients of the materials, who themselves involve new participants in the “viral process” and increase the reach of the audience.

When using viral content, the concept of "virality" is often referred to as the ability of information to spread on social networks through the voluntary transfer of materials between people. You could even say that virality - This is "friendly spam" in social networks, the basis of social viral marketing and viral content in particular.

Material costs of a webmaster for the formation of viral information are small, and the resulting effect is enormous. Viral content attracts traffic, promotes brand awareness and citation, and encourages people to be active. However, a unified and reliable scheme for creating viral content has not yet been invented.

Forms of viral content

The form of expression can be different: text, video, photo, animation, audio. But the best effect is obtained when combining, combining visual information with text and links. For example, the following schemes work well:

• "Picture + Text";
• "Video + Text";
• "Picture + Text + Link";
• "Video + Link + Text".

But the combination of picture and video in one note reduces the clarity of the material, confuses users.

In creating viral materials, it is important to consider the effect of the first emotional impact on the recipient, which usually lasts no more than 2-3 seconds... If in this short time the information is noticed, arouses interest and emotions, then the probability of reading (and, therefore, spreading) the message will increase.

Principles of viral content

When developing and forming a viral message, you need to decide on the form and theme. We'll talk about the latter below, but will it be enough? No. In addition to answering the question "What to write about?", It is important for you to know the answer to an equally significant question - "How to write?" So, you have to:

Viral content in examples

No one will be able to determine in advance whether this or that content will go viral. It is possible to assess the virality of information on social networks only by testing and experiments. Nevertheless, a number of common qualities, rules, criteria were identified that increase the likelihood of a viral effect.

You only need one. Arouse genuine interest, touch the recipient's feelings, touch his emotions - only this will induce him to distribution of content... In this case, you need not only to choose any popular topic, but also to send the message to the desired target group. Next, let's see how this might look like with examples.

Popular fashion themes, trends and people

Popular topics always interest people. If novelty and uniqueness are added to popularity, the virality of the content grows. In fact, this triggers a social desire to appear as an innovator, following fashion and trends, following popular trends and trends. A person in an effort to improve his status in society can share interesting news.

If the recipient of the content is faced with fashionable topics or trends that are "on everyone's lips", he can convey a message (depending on the social openness and activity of the person). And he will hasten to repost before friends and colleagues.

An obvious example is Mark Zuckerberg's Facebook page. The last post got 222 thousand "likes", 10.700 comments in 3-4 days! And the numbers keep going up:

Unusual, unusual themes

When people are faced with unusual topics, they start to wonder. And interest is the first factor affecting viral information. Perhaps, until this moment, the person did not know about the existence of some things, did not pay attention to it. Having met an unusual note on a social network, people begin to think, be interested in the issue.

For example, a note about the desperation of wedding photographers on the VKontakte social network. The topic, which no one thought about, gained more than 4,000 thousand likes and 500 shares in less than a day. This is despite the fact that the post is not 100% unique, was published earlier in other communities and was already familiar to people, but in a different form:

Contests, promotions and marathons. Free prizes and gifts

Note: Free prizes and gifts have long been successfully used in collecting subscribers on large blogs, social resources like YouTube, in social networks... The technology is very simple (a gift for an action), and therefore understandable and effective!

Users take note of useful information, add it to bookmarks, and re-read it. In order not to lose valuable content and records, people keep them on the pages, ensuring the content virality.

Humor, laughter, "jokes", bloopers, funny photos and videos

Humor is a universal topic that is not limited to either linguistic or geographic boundaries. About 40% of all viral content is formed on the topic of humor, and the reader has seen such notes more than once. Sometimes the theme of positivity and humor is used as an addition to other publications.

Everyone, without exception, likes high-quality humor and positivity, but this topic is very difficult to link with sales, with the commercial goals of a web project. If the goal is to sell, then humor is used as an addition to attract attention.

Here's an example - this post got more than 300,000 views in a few days!

Breaking news, important statements

Distribution of this type of content usually involves mature people following the news. For the younger generation, statements of urgency are less effective.

Breaking news of the day is often negative, which is difficult to use in order to sell goods or services. If the news is positive, in line with the topic of the project, they must be used to generate viral content. Firstly, the news will be of interest to readers, and secondly, it will contribute to the spread of links and mentions of a commercial resource.

To find examples of such content, just go to the pages of any major news portal or web media representation.

Little-known facts, discoveries of science

Information of a pseudo-educational nature can be found in any of the topics and used to create viral content. People like the truth, they like to learn new things, they are interested in discoveries and facts. The good news is that they are concretized, precise and indisputable.

Absurd, controversial and resonant materials

Such news is very actively discussed by users, but not always in a positive light. Absurd and controversial information, as you might guess, will have both supporters and opponents. The more controversial an issue is raised in the news, the higher the virality and virality.

The negative side here is the growing number of negative reviews. It is extremely difficult to predict the reaction of users to controversial information of resonant content, but its virality is guaranteed. Linking this topic to sales and commerce will also be challenging.

An example - a video with the theory that we live in a black hole has gained over 300,000 views. The topic, of course, is very controversial, but interesting.

Shocking cases, stories, photos and videos

Like absurd news, shocking information will not please all recipients. If this viral theme is misused, the opposite effect can work. It often happened that, due to shocking materials, communities in social networks instantly lost thousands of their unprepared subscribers, whose information caused discontent and indignation.

And if one person agrees to repost such news, then another will hasten to scroll through them, close them, unsubscribe or turn them off in the feed. An illustrative example is YouTube search results for the SHOCK request:

Motivating and educational content

Viral motivating and educational content is saved by people for future use. Over time, there are more and more reposts, materials are distributed on the social network.

These can be articles, courses, webinar recordings, training invitations, books, podcasts, infographics, links to educational websites, motivating images, photos and animations. Like other topics, this area is popular on social networks. Especially if the disseminated information clearly prompts you to repost.

The publication of materials on the user's personal page makes the information available and open to the social environment of a person.

An example is a high-quality motivational video about the benefits of entrepreneurship over work. More than 350,000 views.

Emotional and sensual content for girls

Obviously, if the reader is a girl, then she herself can name a lot of examples of viral posts of such content. For the male half of the readers, we emphasize that here the information is exclusively feminine, sensual, and emotional.

It can be stories, videos, images on the theme of love, relationships, romance. Here you can also use the themes of psychology, family, infidelity, motherhood, marriage, weddings, as well as related areas. An example of such a publication, which gained more than 1000 reposts and 3500 likes in a couple of hours:

Selections, lists, collections, lists

Collections can be made by any, in accordance with the theme of the project. For example, take a look at a movie community post with a selection of 10 puzzle movies. In a couple of hours, more than 590 people shared the record, and this is only within 1 single group. The number of shares is growing every minute:

Let's summarize

Any content can become viral if the conditions are met, which are divided into 2 stages (creation and publication):

1. Viral content creation... When developing potentially viral materials, you need to think down to the smallest detail:
   • type of information (photo, video, text, etc.);
   • topic (according to the topic of the promoted project);
   • format (group news, profile wall post, YouTube channel post);
   • emotional landmark (what emotions and feelings the content should evoke).
2. Posting content on social networks (sowing information) - selection of ideal conditions:
   • time of publication. The peak of the concentration of the target active audience most often falls in the evening;
   • location. From popular communities, thematic profiles or channels where there is an abundant target active audience, viral content will spread faster and easier.

All 6 factors are critical to a successful launch viral content. We especially emphasize the activity of the audience, because it is active people who participate in the transfer of materials, make reposts and put likes, follow the links. It is unlikely that high virality can be achieved without at least one of the conditions. Namely, this factor predetermines the degree of information dissemination in social networks.

Research history

For the first time the existence of a virus (as a new type of causative agent) was proved in 1892 by the Russian scientist D.I. After many years of research on diseases of tobacco plants, in a work dated 1892, DI Ivanovsky comes to the conclusion that tobacco mosaic is caused by "bacteria passing through the Chamberlain filter, which, however, are not able to grow on artificial substrates."

Five years later, in the study of diseases in cattle, namely, foot and mouth disease, a similar filterable microorganism was isolated. And in 1898, when reproducing the experiments of D. Ivanovsky by the Dutch botanist M. Beijerinck, he called such microorganisms "filterable viruses." In an abbreviated form, this name began to denote this group of microorganisms.

In subsequent years, the study of viruses played an important role in the development of epidemiology, immunology, molecular genetics, and other branches of biology. Thus, the Hershey-Chase experiment became decisive proof of the role of DNA in the transmission of hereditary properties. Over the years, at least six more Nobel Prizes in Physiology or Medicine and three Nobel Prizes in Chemistry were awarded for research directly related to the study of viruses.

Structure

Simply organized viruses are composed of a nucleic acid and several proteins that form an envelope around it - capsid... An example of such viruses is the tobacco mosaic virus. Its capsid contains one type of protein with a small molecular weight. Complexly organized viruses have an additional envelope - protein or lipoprotein; sometimes in the outer shells of complex viruses, in addition to proteins, carbohydrates are contained. The causative agents of influenza and herpes are examples of complexly organized viruses. Their outer membrane is a fragment of the nuclear or cytoplasmic membrane of the host cell, from which the virus enters the extracellular environment.

The role of viruses in the biosphere

Viruses are one of the most common forms of the existence of organic matter on the planet in terms of number: the waters of the oceans contain a colossal number of bacteriophages (about 250 million particles per milliliter of water), their total number in the ocean is about 4 × 10 30, and the number of viruses (bacteriophages) in ocean bottom sediments practically does not depend on depth and is very high everywhere. Hundreds of thousands of species (strains) of viruses live in the ocean, the overwhelming majority of which have not been described, much less studied. Viruses play an important role in the regulation of the population size of some species of living organisms (for example, the wildness virus reduces the number of Arctic foxes several times over a period of several years).

Position of viruses in the living system

Origin of viruses

Viruses are a collective group that has no common ancestor. Currently, there are several hypotheses explaining the origin of viruses.

The origin of some RNA viruses is associated with viroids. Viroids are highly structured circular RNA fragments replicated by cellular RNA polymerase. It is believed that viroids are "escaped introns" - insignificant regions of mRNA cut out during splicing, which accidentally acquired the ability to replicate. Viroids do not encode proteins. It is believed that the acquisition of coding regions (open reading frame) by viroids led to the appearance of the first RNA-containing viruses. Indeed, examples of viruses containing pronounced viroid-like regions (hepatitis Delta virus) are known.

Examples of structures of icosahedral virions.
A. A virus that does not have a lipid envelope (eg, picornavirus).
B. An enveloped virus (eg herpesvirus).
The numbers indicate: (1) capsid, (2) genomic nucleic acid, (3) capsomere, (4) nucleocapsid, (5) virion, (6) lipid envelope, (7) membrane proteins of the envelope.

Detachment ( -virales) Family ( -viridae) Subfamily ( -virinae) Genus ( -virus) View ( -virus)

Baltimore classification

Nobel laureate biologist David Baltimore proposed his own classification scheme for viruses based on differences in the mechanism of mRNA production. This system includes seven main groups:

• (I) Viruses containing double-stranded DNA and lacking an RNA stage (for example, herpes viruses, poxviruses, papovaviruses, mimivirus).
• (Ii) Viruses containing double-stranded RNA (eg rotaviruses).
• (III) Viruses containing a single-stranded DNA molecule (eg parvoviruses).
• (Iv) Viruses containing a single-stranded RNA molecule of positive polarity (eg, picornaviruses, flaviviruses).
• (V) Viruses containing a single-stranded RNA molecule of negative or double polarity (eg, orthomyxoviruses, filoviruses).
• (Vi) Viruses containing a single-stranded RNA molecule and having in their life cycle the stage of DNA synthesis on the RNA matrix, retroviruses (for example, HIV).
• (VII) Viruses containing double-stranded DNA and having in their life cycle the stage of DNA synthesis on an RNA template, retroid viruses (for example, hepatitis B virus).

Currently, both systems are used simultaneously to classify viruses, as complementary to each other.

Further division is carried out on the basis of such traits as the structure of the genome (the presence of segments, circular or linear molecules), genetic similarity with other viruses, the presence of a lipid membrane, taxonomic affiliation of the host organism, and so on.

Viruses in popular culture

In literature

• S.T.A.L.K.E.R. (fantasy novel)

In cinema

• Resident Evil "and its sequels.
• In the sci-fi horror film 28 Days Later and its sequels.
• In the plot of the disaster film "Epidemic" there is a fictional "motaba" virus, the description of which resembles the real Ebola virus.
• In the movie "Welcome to Zombieland".
• In the film "Purple Ball".
• In the film "Carriers".
• In the film "I Am Legend".
• In the film "Contagion".
• In the film "Report".
• In the film "Quarantine".
• In the movie "Quarantine 2: Terminal".
• In the TV series "Regenesis".
• In the TV series The Walking Dead.
• In the TV series "Closed School".
• In the film "Carriers".

In animation

In recent years, viruses have often become "heroes" of cartoons and animated series, among which one should mention, for example, "Osmosis Jones" (USA), 2001), "Ozzy and Dricks" (USA, 2002-2004) and "Virus Attacks" (Italy, 2011).

Notes

1. In English . In Latin, the question of the plural of a given word is controversial. The word lat. virus belongs to a rare variety of the II declension, words of the neuter genus in -us: Nom.Acc.Voc. virus, Gen. viri, Dat. Abl. viro. Lat is also inclined. vulgus and lat. pelagus; in classical Latin, the plural is fixed only in the latter: lat. pelage, a form of ancient Greek origin, where η<εα.
2. Taxonomy of viruses on the International Committee on Taxonomy of Viruses (ICTV) website.
3. (English))
4. Cello J, Paul AV, Wimmer E (2002). Chemical synthesis of poliovirus cDNA: generation of infectious virus in the absence of natural template. Science 297 (5583): 1016-8. DOI: 10.1126 / science.1072266. PMID 12114528.
5. Bergh O, Børsheim KY, Bratbak G, Heldal M (August 1989). "High abundance of viruses found in aquatic environments." Nature 340 (6233): 467-8. DOI: 10.1038 / 340467a0. PMID 2755508.
6. Elements - science news: By destroying bacterial cells, viruses actively participate in the cycle of substances in the depths of the ocean