What is the danger of viral diseases. Deadly nine: the most terrible infections in the world (11 photos)

So what is the deadliest virus on earth? You might think this is a simple enough question to answer, but it turns out there is more than one way to determine the lethality of viruses. For example, is it a virus that kills the most people (overall mortality rate) or is it a disease that has a high mortality rate, i.e. kills the most number of infected people. For most of us, this will be the disease with the highest mortality rate, it is definitely a death sentence if you ever get it.

Ironically, it is a series of diseases that have a reassuringly low mortality rate that actually kills millions of people. There's a reason for this - it's the viruses that cause the most dangerous diseases, usually killing themselves by killing their hosts faster than they can spread. two especially good examples of this phenomenon are: the Ebola virus, with a 90% fatality rate, which has killed about 30,000 people to date, and the Spanish flu pandemic, which has killed approximately 100 million people, despite the fact that it has a mortality rate of less than 3%.

In addition to the two measures of overall death rate and death rate mentioned above, there is also a historical dimension: which virus has killed the most people throughout history?

Given these various criteria to determine which virus is the most deadly, we will take all of these into account to not only compile the top 10 viruses, but also provide some individual statistics at the end of the article.

10 Dengue Fever

A photo. Mosquito

Dengue fever is a mosquito-borne infection that was first described almost 2,000 years ago in China. After a gradual spread to other countries with yellow fever mosquitoes (lat. Aedes aegypti), the spectrum of diseases expanded significantly in the 18th century. This was due to the slave trade, as well as the activities of people in the Second World War, when the spread accelerated, especially of more dangerous forms of diseases.

IN last years globalization has had its effect on dengue fever rates, which have risen 30 times since the 1960s.

As with many of these illnesses, the vast majority of people either had no symptoms or had rather mild symptoms not characteristic of a fever. Dengue fever is sometimes referred to as "breakbone fever", which refers to severe pain that can be felt in the muscles and joints.

For those unfortunate, the disease can develop into "severe dengue" with the risk of potential death as a result of dengue hemorrhagic fever and dengue shock syndrome. This occurs in less than 5% of cases, the main reason for this is an increase in the permeability of blood vessels. This can lead to vomiting of blood, organ damage, and shock.

Today, up to 500 million people are infected with endemic dengue every year in 110 countries, resulting in approximately 20,000 deaths. The grim reality is that these numbers will continue to rise.

9. Smallpox

A photo. smallpox patient

Smallpox is eradicated, isn't it? WHO assures that it has not been since 1979, however, the United States and former USSR conducted scientific research on virus samples. According to some rumors after the breakup Soviet Union, some of these samples are missing. Even if the variola virus died out, it could presumably be reengineered from a digital viral genome and inserted into a poxvirus shell.

The good news is that all smallpox targets are now extinct in the wild. Although historically this has had a devastating impact. Smallpox appeared around 10,000 BC, at that time it led to mass death of people. Smallpox is contagious and, of course, in those distant times, the mortality rate reached 90%.

The most terrible period for people was when smallpox was brought to Europe by European explorers. New world in the 18th century. By accident or not, it is estimated that about half of the Australian Aboriginal population was killed by smallpox in the early years of British colonization. The disease also took its toll on the indigenous populations of the Americas.

Despite the fact that Edward Jenner developed the smallpox vaccine in 1796, it caused an estimated 300-500 million deaths in the 1800s.

In terms of the appearance of smallpox, it is especially shocking that the body is covered in blisters filled with liquid. It can occur in the mouth and throat, and in some cases smallpox has led to complications such as blindness. Mortality from this disease largely depends on the course that the disease will develop, if it is malignant and hemorrhagic smallpox, it will invariably lead to death.

8. Measles

A photo. child with measles

Most people in developed countries don't even remotely consider measles dangerous. We are used to the fact that about 90% of all children by the time they reach the age of 12 will already have measles. Currently, with routine vaccination being carried out in many countries, the incidence rates have been significantly reduced.

But what may shock you is that between 1855 and 2005, measles claimed 200 million lives worldwide. Even in the 1990s, measles killed over 500,000 people. Even today, with the advent of cheap and affordable vaccines, measles is one of the leading causes of death among young children, claiming more than 100,000 lives each year.

Measles has caused the most devastation in communities that have not previously been exposed to it. In the 16th century, measles was introduced to Central America by Europeans. In particular, Honduras lost half of its population in 1531 during a measles epidemic.

In frequent cases, measles leads to fever, cough and rash. However, complications are quite common and this is where the danger lies. In about 30% of cases, symptoms range from relatively mild, such as diarrhea, to pneumonia and inflammation of the brain, all of which can lead to death. Blindness is another complication.

7. Yellow fever

A photo. Memorial in Savannah, Georgia

Another mass killer in history is yellow fever. Also known as "yellow plague" and "vomito negro" (black vomit), this acute hemorrhagic disease has caused a number of serious outbreaks over the centuries.

Most people recover completely from yellow fever, but in about 15% of cases, a second, more serious stage of the disease develops. In these cases, there may be bleeding from the mouth, nose, eyes, or stomach. About 50% of patients who enter this toxic phase die within 7-10 days. Although in general the mortality rate reaches 3%, during epidemics it reached 50%.

Like most such viral infections, yellow fever originated somewhere in Africa. In the early colonial years, it was noted that outbreaks in the village among the natives did not lead to serious complications, it was more like flu-like symptoms, while most of the European colonists died. This difference in disease severity is believed to be due to long-term exposure to low doses during childhood, which results in some immunity.

It can be argued that there is a certain amount of gloating in the fact that slavery and exploitation of Africa led to epidemics in Europe and North America in the 18th and XIX centuries. Probably the most famous of these was an outbreak in 1792 in Philadelphia, then the capital of the United States. President George Washington was reported to have fled the city while 10% of those who remained died.

Yellow fever swept across America, claiming between 100,000 and 150,000 lives in the 18th and 19th centuries.

Today, despite the existence of an effective vaccine, there are regions in which 200,000 people worldwide fall ill with yellow fever every year, claiming 30,000 lives each year.

6. Lassa fever

A photo. Electron micrograph of Lassa virus

You might think of Lassa as a “mild version of Ebola,” but then again, it kills as many people every year in West Africa as did Ebola at the height of the 2013-15 epidemic. In addition, the symptoms are easily confused with Ebola, both of which are classified as acute viral hemorrhagic fevers. Lassa fever infects virtually every tissue in the human body and outbreaks are usually triggered by native Mastomys rats.

If you doubt the dangers of Lassa fever, then its biosafety level 4 (BSL-4) should convince most of you. This is the highest level of biosecurity, designed to deal with pathogens that can cause death and for which there is no vaccine or treatment. To have general idea, MRSA, HIV and hepatitis viruses are classified as Biosafety Level 2.

Lassa fever causes an average of 5,000 deaths each year. It is estimated that more than 300,000 people are infected endemicly throughout West Africa each year. Although most do not have any symptoms, those who do have a mortality rate of 15-20%. During epidemics, the mortality rate of Lassa fever reaches 50%. It doesn't quite look like Ebola or Marburg virus, but it's still dangerous.

5. Hepatitis

A photo. Hepatitis C virus

Hepatitis is the name given to a series of viral diseases that attack the liver. There are 5 types of infectious hepatitis, which are designated by letters from A to E (A, B, C, D, E). Of these, hepatitis B and hepatitis C are the most serious, together claiming nearly a million lives a year. They are often passed from mother to child, but can also be transmitted through blood transfusions, tattoos, dirty syringes, and sexual activity.

Hepatitis B reaps the highest number of deaths per year (about 700,000). This is a rather inconspicuous disease that is asymptomatic. Most deaths are the result of a disease that slowly attacks a person's liver over several years, eventually leading to cancer or cirrhosis of the liver. Although infection with hepatitis B in an adult usually results in an acute episode of the disease, it ends in full recovery. Infected, as a rule, children who are more predisposed to the development of the disease in the long term.

Although the overall death rate from hepatitis C is lower than that of hepatitis B, it still kills approximately 350,000 people each year, mostly in developing countries. The figures show that about 200 million people (or 3% of the total population) are living with hepatitis C.

4 Rabies

A photo. Patient in the last stage of rabies

Rabies is one of the deadly diseases belonging to the Lyssavirus genus. This name is derived from Lys (Lyssa), the Greek goddess of rage, madness and anger, the word itself comes from the Latin "madness". This is one of the most terrible diseases of mankind, which has been known since ancient times and there is every reason for this.

The best-known form of rabies is referred to as "furious rabies" and affects 80% of those infected. This stage includes the classic symptoms of confusion, agitation, paranoia, and terror. An infected person may also exhibit rabies (fear of water). In this seemingly strange state, the patient panics when given a drink. Rabies infects the salivary glands at the back of the mouth, so it can be transmitted by a simple bite. This infection also causes the throat muscles to go into excruciating spasms, resulting in increased salivation.

Rabies is contracted when an infected animal, usually a dog or bat, bites or scratches a person. Although some flu-like symptoms may occur after a bite, the disease is usually asymptomatic during the incubation period. This usually lasts 1-3 months, but it can take years for the infection to travel through the nervous system to the brain.

Rabies is difficult to diagnose and if a suspicious bite is left unnoticed, neurological symptoms may develop. At this stage it is definitely too late for the patient, rabies has a near 100% lethality within a few days. In fact, only 6 people have survived rabies and the first was Jeanna Giese in 2005. She was a new approach (the Milwaukee Protocol) in the fight against this disease, she was put into an artificial coma and she survived, almost completely recovered. While successful in this case, this method still has an approximately 8% chance of success.

Luckily, being bitten by an animal infected with rabies is no longer a death sentence. If you receive post-exposure prophylaxis (PEP) treatment within 10 days, you have an almost 100% chance of survival. There is also an equally effective vaccine.

However, almost 60,000 people die from rabies every year, mostly in Africa and South Asia. More than one third of these deaths occur in India, where dogs are still the main culprits. More details about this disease and can be found in our other article.

3. Viral hemorrhagic fevers (Filoviruses)

A photo. Ebola outbreak in 2015

If any disease can cause fear in the 21st century, it is viral hemorrhagic fevers from the filovirus family. These include the Ebola virus and the Marburg virus, both do not effective treatment, there is no vaccine and lethality reaches 90%. Having very unpleasant symptoms - these are potentially deadly viruses on Earth.

From a diagnostic point of view, Marburg and Ebola are clinically indistinguishable. The name of this group of viruses is a clue to some of the symptoms, it is obvious that these fevers are accompanied by pain throughout the body, joints, muscles, abdominal pain, headaches. The hemorrhagic aspect is due to the fact that filoviruses interfere with the blood coagulation mechanism, thereby causing bleeding from any orifice of the human body. More than likely, death is usually due to multiple organ failure, necrosis of internal tissues.

Ebola and Marburg usually appeared in isolated villages in Central Africa as a result of small outbreaks that quickly destroyed themselves. However, in 2013, the Ebola virus arrived in the West African country of Guinea, where it was not recognized as such until it began to spread rapidly. Over the next 2 years, the Ebola epidemic raged in six countries, infecting 25,000 people, of whom about half died.

The largest outbreak of the Marburg virus was in 2004 in Angola. Of the 252 infected, 227 died, i.e. 90%. During early epidemics, the death rate in the Congo was as high as 83%.

The Marburg and Ebola viruses are believed to have been transmitted to humans from wild animals. Although the first cases of Marburg virus infection occurred with researchers working with African green monkeys, bats are thought to be the natural host of the virus. This also applies to the Ebola virus, which is why bats are considered the main carriers of some of the most terrible diseases on Earth.

2. HIV / AIDS

A photo. HIV virions infect cells

Over the past three decades, AIDS has been the mainstream news, it is a devastating disease. Tremendous progress in the field of antiretroviral drugs means that taking the right medication for HIV infection is not the death sentence it used to be.

This disease is another that originated in Central Africa, where it lurked in monkey populations for millions of years until it crossed over into humans in the mid-20th century. It is not known exactly how this happened, but it is believed that the monkey SIV (simian immunodeficiency virus) transmitted the virus to humans through eating meat, the virus later mutated and we currently know it as HIV.

It is suspected that HIV existed for some time before it became mainstream news, with the first reported case occurring in the Congo in 1959.

The main reason for not being direct treatment HIV is the fact that it is constantly and rapidly changing. It reproduces rapidly (about 10 billion new individual virions per day) and the rate of mutation is very high. Even in one individual, the genetic diversity of a virus can resemble a phylogenetic tree, with different organs infected by virtually different species.

Today, about 40 million people are living with HIV, mostly in sub-Saharan Africa. Unfortunately, only half of the people who are infected have access to the medicines they need, which is why the global AIDS death rate is so high. AIDS is estimated to claim about 2 million lives each year, and over the past 30 years, the virus has claimed the lives of more than 25 million people.

1. Flu

A photo. Spanish flu patients

The flu is the most widely known virus and is hardly the most exciting of our list of deadly viruses. Everyone has had the flu, and for most it didn't end well. However, every year the flu causes a large number of deaths and the most vulnerable group of the population are the old, the very young and the sick. Although a safe and effective vaccine was developed over 60 years ago, the flu still kills up to half a million people every year.

But this is only a baseline, in addition to this, random devastating epidemics occur when virulent strains of the virus develop. The Spanish flu of 1918 is a prime example of this. It is believed to have infected nearly a third of the world's population and claimed up to 100 million lives. During the epidemic, the mortality rate was 20% compared to the normal seasonal flu of 0.1%. One of the reasons why the Spanish flu was so deadly was because it killed healthy people, a particular strain caused an overreaction immune system, which is known as a cytokine storm. Therefore, people with strong immune systems were most at risk.

Other diseases have not even come close to these figures, which is what makes the flu so dangerous. The influenza virus has the ability to frequently combine and mutate into new strains. Fortunately, at present, the most deadly strains are different from the most contagious strains. One fear is that a potentially deadly H5N1 avian flu strain that cannot be transmitted from person to person, for example, would need a small genetic "event" to create a possible epidemic. Although there have been just over 600 cases of avian influenza to date, almost 60% of them have been fatal, making it one of the most dangerous diseases for humans.

How to protect yourself from viruses, avoid viral diseases? Why are viruses dangerous? (10+)

Viral infections. Danger. Prevention

How do viruses live and reproduce?

First, let's look at how viruses live and multiply. The virus is a core with DNA in the shell. That is, a virus is genetic information sealed in a capsule. Viruses do not have a mechanism for reproduction and nutrition. Viruses cannot themselves consume environment energy and nutrients to share. To continue its kind, a virus needs a cell. Only when he gets into it does he begin to use its mechanisms of nutrition and reproduction to reproduce himself. Viral infection occurs.

Why are viral infections dangerous?

With a viral infection, foreign DNA is introduced into the cells of the body. The penetration of foreign DNA into the human body is sometimes described in horror films, but in fact it happens all the time in the form of viruses.

But here I will briefly list simple rules. Observe the regime of the day, sleep and rest enough time. Don't stress yourself out, take it easy. A short burst of emotions stimulates the immune system, but constant stress suppresses the body's defenses. Eat right. Do not overeat, eat more dietary fiber and natural vitamins, fewer calories. Moderate exercise stress useful for immunity, overloads are harmful. Do not use antibiotics and hormones without a doctor's prescription. Even if the doctor prescribed them to you, you must first consult with another doctor, make sure that such treatment is necessary, and only then decide on treatment with these dangerous drugs. Have regular intimacy or avoid sex altogether. The fact is that testosterone strongly suppresses the immune system. By the way, testosterone is released in both men and women. Everything said here is true for both sexes. If you give up sex, then in a year or three the level of this hormone in most people will decrease, the attraction will practically disappear, everything will be fine with immunity. Regular intimacy also helps maintain normal levels of this hormone. But periods of abstinence, followed by great activity in this area, can finish off almost any immunity. Avoid abrupt and frequent changes in climate, latitude and time zones. Do not smoke, do not abuse alcohol.

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Who are the representatives of the microcosm - viruses and bacteria - to each other? Can they be considered enemies, friends, blood relatives or partners? We will understand their interaction and role in the human body.

Most often, a person gets acquainted with viruses and bacteria during the cold season. Acute respiratory infections are one of the most common diseases in the world. Most of Such diseases arise due to viruses and bacteria that enter the human body along with the inhaled air and settle on the mucous membranes of the nose or mouth 1 .

To understand the process of infection, we can draw an analogy with any public institution, which in our case is a human body. Through open doors, various guests enter the institution - viruses and bacteria. Some bacteria are an intelligent public and do no harm, while some are strictly forbidden to enter: they can provoke a real conflict. As for viruses, they are, for the most part, bandits. Don't expect anything good from them.

Against unwanted persons outside and inside the institution there is a security system - human immunity. Sometimes the immune system does not cope with its tasks, gets tired or is “distracted” by bacteria, letting dangerous viruses inside, which immediately begin a raider takeover.

So what is the main difference between them? First you need to clearly understand what they are, and on the basis of this, determine the difference and the principle of impact on the body.

What are viruses

A virus is the smallest organism that can exist and multiply only inside living cells. In the external environment, the virus is found in microparticles of biological material, but it multiplies exclusively in the cells of living beings. In other words, the virus is not active until it is inside a person 2 .

And it gets there like this:

Airborne, like most respiratory infections
When used dirty water, with food, in case of non-observance of hygiene rules
From mother to unborn child
Contact - with close contact through the skin or mucous membranes
Parenteral way - bypassing the gastrointestinal tract, by injection

After entering the body, the virus first attaches to the cell, then delivers its biological genome into it, loses its shell, and only then multiplies. After reproduction, the virus leaves the cell, and the infectious agent spreads along with the blood, continuing the total infection. Viruses can suppress the immune system 2 .

What is bacteria

A bacterium is a complete, albeit unicellular, organism. She knows how to multiply due to division, which she actively does in nature or inside a person 3.

Not all bacteria cause infectious diseases. Some are useful and live in the organs of the body. For example, lactic or bifidobacteria, which live in the intestines and gastric tract, are actively involved in the process of human life and actually form part of its immune defense 3 .

The entry of bacteria into the body follows the path of viruses. But bacteria multiply more often outside the cell than inside it. The list of diseases that develop as a result of their penetration into the human body is extremely long. Bacteria can cause 3:

Respiratory diseases (most often they are caused by staphylococci and streptococci)
Infections of the gastrointestinal tract (provoked by E. coli and enterococci)
Nervous system disorders (caused by meningococci)
A number of diseases of the reproductive system, etc.

Reproducing, they spread through the bloodstream, which leads to generalization of the infection and clinical aggravation of the patient's condition. Bacteria are also able to suppress the immune system, making it harder for the body to resist viruses 3 .

How is a virus different from a bacterium

Thus, both viruses and bacteria can infect the body, causing infection. The key difference between them is in the mechanism of reproduction. Viruses cannot reproduce in the external environment, so they need to infiltrate the cell. Bacteria reproduce by division and can live in the external environment for a long time, waiting to enter the human body. Accordingly, the mechanisms for antibacterial and antiviral protection should also differ 4 .

Let's sum up summary. There are 4 differences between a virus and a bacterium:

The size and form of existence. A virus is the simplest life form, a bacterium is a single-celled living being.
Vitality. The virus exists only inside the cell and infects it, after which reproduction (cloning) occurs. The bacterium lives a full life, multiplying by division, and the body for it is only a favorable place of existence.
manifestation form. Viruses tend to manifest themselves as an increase in body temperature, general weakness, muscle and joint pain. Bacteria manifest themselves as unhealthy secretions (purulent or as a specific plaque).

Typical viral diseases: SARS, influenza, herpes, measles and rubella. They also include encephalitis, hepatitis, smallpox, HIV, etc.

Typical bacterial diseases: syphilis, whooping cough, cholera, tuberculosis, diphtheria, typhoid and intestinal infections, STIs.

It happens that both of them cause the same disease together. Such a symbiosis requires special treatment. Examples are: sinusitis, tonsillitis, meningitis, pneumonia and other diseases 5 .

Fight against viruses and bacteria

It is impossible to completely protect yourself from viruses and bacteria. A person is constantly attacked by a huge number of microorganisms and the main barrier in their path is immunity. Therefore, it is important to strengthen and keep the immune system in a “combat” state, especially during the cold season and during periods of seasonal illness.

The IRS®19 immunomodulator will become an assistant on the way to a healthy and strong immune system. It contains a mixture of bacterial lysates, which are specially isolated parts of pest bacteria. Lysates activate the immune system and direct it to fight bacteria and viruses. The drug has a high level of safety and can be prescribed for the prevention of infections in adults and children older than 3 months. It has been tested many times and has shown excellent results in the fight against infections, including SARS 6 .

06.09.2017 17:12

Viral infections are diseases that every person encounters many times throughout life. Basically, these are respiratory viruses that lead to colds, less often - viruses of childhood infections and other pathologies. However, among all, there are such human virusesthat lead to very dangerous, sometimes fatal diseases. There is even a kind of rating of viral infections, the top 10 most dangerous viruses on the planet. What are these infections?

OTHER DANGEROUS VIRUSES

Leads to the formation of the fever of the same name, which occurs in Asia and Africa. It is transmitted from sick to healthy through carriers, gives massive epidemics with a mortality rate of up to 50%. It is difficult to diagnose and treat such a fever. Smallpox is considered to be no less dangerous virus. Enormous forces and means were thrown into the fight against it, thanks to which it was last registered in 1977. But it is important to know that in the laboratories of many countries it is stored as a biological weapon, therefore, it does not lose its relevance.
The rabies virus is a specific infection transmitted through the bites of domestic and wild animals. An infected person can only be saved at an early stage by introducing a special anti-rabies vaccine. In advanced cases, patients die in severe agony. Worldwide, only 3 survivors of the infection have been reported.
The Lassa virus, common in African countries, leads to a special fever, which often ends in death. When the disease affects many internal organs, the nervous system and blood, the disease is highly contagious and causes epidemics.
HIV is the most scandalous and most famous of the deadly viruses. It leads to the gradual destruction of one's own immune system, which gives the AIDS syndrome. For many years, the development of a cure for this infection has been underway, today they have learned to control it and prolong the life of patients, but about complete elimination virus from the body has not yet been declared.

Viral diseases infect cells in which there are already violations, which is what the pathogen uses. Modern research proved that this happens only with a strong weakening of the immune system, which is no longer able to adequately fight the threat.

Features of viral infections

Types of viral diseases

These pathogens are usually distinguished by a genetic trait:

DNA - human catarrhal viral diseases, hepatitis B, herpes, papillomatosis, chicken pox, lichen;
RNA - influenza, hepatitis C, HIV, polio, AIDS.

Viral diseases can also be classified according to the mechanism of influence on the cell:

cytopathic - the accumulated particles break and kill it;
immune-mediated - the virus embedded in the genome sleeps, and its antigens come to the surface, putting the cell under attack by the immune system, which considers it an aggressor;
peaceful - the antigen is not produced, the latent state persists for a long time, replication starts when favorable conditions are created;
degeneration - the cell mutates into a tumor.

How is the virus transmitted?

The spread of a viral infection is carried out:

Airborne. Respiratory viral infections transmitted by drawing in particles of mucus sprayed during a sneeze.
Parenterally. In this case, the disease passes from mother to child, during medical manipulations, sex.
Through food. Viral diseases come with water or food. Sometimes they stay dormant for a long time, appearing only under external influence.

Why are viral diseases epidemic?

Many viruses spread quickly and massively, which provokes the emergence of epidemics. The reasons for this are as follows:

Ease of distribution. Many serious viruses and viral diseases are easily transmitted through saliva droplets inhaled. In this form, the pathogen can maintain activity for a long time, therefore it is able to find several new carriers.
reproduction rate. After entering the body, the cells are affected one by one, providing the necessary nutrient medium.
Difficulty of elimination. It is not always known how to treat a viral infection, this is due to the lack of knowledge, the possibility of mutations and the difficulties of diagnosing - at the initial stage it is easy to confuse with other problems.

Symptoms of a viral infection

The course of viral diseases may differ depending on their type, but there are common points.

Fever. It is accompanied by a rise in temperature to 38 degrees, without it only mild forms of SARS pass. If the temperature is higher, then this indicates a severe course. It does not last longer than 2 weeks.
Rash. Viral skin diseases are accompanied by these manifestations. They may look like spots, roseola, and vesicles. Characteristic for childhood, in adults, rashes are less common.
Meningitis. Occurs with an enterovirus and is more common in children.
Intoxication- loss of appetite, nausea, headache, weakness and lethargy. These signs of a viral disease are due to toxins released by the pathogen in the course of activity. The strength of the impact depends on the severity of the disease, it is harder for children, adults may not notice it.
Diarrhea. Characteristic of rotaviruses, the stool is watery, does not contain blood.

Human viral diseases - list

It is impossible to name the exact number of viruses - they are constantly changing, adding to the extensive list. Viral diseases, the list of which is presented below, are the most famous.

Flu and cold. Their signs are: weakness, fever, sore throat. Antiviral drugs are used, when bacteria are attached, antibiotics are additionally prescribed.
Rubella. The eyes, respiratory tract, cervical lymph nodes and skin are affected. It spreads by airborne droplets, accompanied by high fever and skin rashes.
Piggy. The respiratory tract is affected, in rare cases, the testes are affected in men.
Yellow fever. Harms the liver and blood vessels.
Measles. Dangerous to children, affects the intestines, respiratory tract and skin.
. Often occurs in the background of other problems.
Polio. Penetrates into the blood through the intestines and breathing, with brain damage, paralysis occurs.
Angina. There are several types, characterized by headache, heat, severe sore throat and chills.
Hepatitis. Any variety causes yellowness of the skin, darkening of the urine and colorless feces, which indicates a violation of several bodily functions.
Typhoid. rare in modern world, affects the circulatory system, can lead to thrombosis.
Syphilis. After the defeat of the genital organs, the pathogen enters the joints and eyes, spreads further. It has no symptoms for a long time, so periodic examinations are important.
Encephalitis. The brain is affected, a cure cannot be guaranteed, the risk of death is high.

The most dangerous viruses in the world for humans

The list of viruses that pose the greatest danger to our body:

Hantavirus. The causative agent is transmitted from rodents, causes various fevers, mortality in which ranges from 12 to 36%.
Flu. This includes the most dangerous viruses known from the news, different strains can cause a pandemic, a severe course affects the elderly and young children more.
Marburg. Opened in the second half of the 20th century, it is the cause of hemorrhagic fever. It is transmitted from animals and infected people.
. It causes diarrhea, the treatment is simple, but in underdeveloped countries 450 thousand children die from it every year.
Ebola. As of 2015, the mortality rate is 42%, it is transmitted by contact with the fluids of an infected person. Signs are: a sharp increase in temperature, weakness, pain in the muscles and throat, rash, diarrhea, vomiting, bleeding is possible.
. Mortality is estimated at 50%, intoxication, rash, fever, and lymph node damage are typical. Distributed in Asia, Oceania and Africa.
Smallpox. Known for a long time, dangerous only to people. Rash, fever, vomiting, and headache are characteristic. The last case of infection occurred in 1977.
Rabies. Transmitted from warm-blooded animals, affects the nervous system. After the appearance of symptoms, the success of treatment is almost impossible.
Lassa. The pathogen is carried by rats, first discovered in 1969 in Nigeria. The kidneys, nervous system are affected, myocarditis and hemorrhagic syndrome begin. The treatment is difficult, the fever claims up to 5 thousand lives annually.
HIV. It is transmitted through contact with the fluids of an infected person. Without treatment, there is a chance to live 9-11 years, its complexity lies in the constant mutation of cell-killing strains.

Fight against viral diseases

The complexity of the fight lies in the constant change of known pathogens, making the usual treatment of viral diseases ineffective. This necessitates the search for new drugs, but present stage development of medicine, most measures are being developed quickly, before the epidemic threshold is crossed. The following approaches have been adopted:

etiotropic - prevention of the reproduction of the pathogen;
surgical;
immunomodulatory.

Antibiotics for a viral infection

In the course of the disease, there is always a suppression of immunity, sometimes it is necessary to strengthen it to destroy the pathogen. In some cases, with a viral disease, antibiotics are additionally prescribed. This is necessary when a bacterial infection joins, which is killed only in this way. With a pure viral disease, taking these drugs will not only worsen the condition.

Prevention of viral diseases

Vaccination- effective against a specific pathogen.
Strengthening immunity- prevention of viral infections in this way involves hardening, proper nutrition, support with herbal extracts.
Precautionary measures- the exclusion of contacts with sick people, the exclusion of unprotected casual sex.