Viral diseases - a list of common ailments and the most dangerous viruses. The most dangerous viruses for humans Why are viruses dangerous?

Bacteria– these are cells without a nucleus that are used by the human body for nutrition and reproduction. They damage body tissues with their enzymes and poison with toxins, causing diseases.

Viruses– extracellular structures that are attached to the membranes of human cells, the epithelium of the mucous membranes. In this way, viruses introduce their genetic material into human cells, continuing to infect new cells and causing the development of disease. Therefore, a viral infection cannot be cured with an antibiotic (viruses do not have cells that the drugs are aimed at destroying), and the virus cannot be purposefully destroyed if it has already entered the cell. Some viruses remain in the human body throughout life (herpesviruses, papillomaviruses and HIV).

What are the symptoms of viral and bacterial infections?

Infectious diseases affect the entire body, causing infectious intoxication. General signs infections are:

fever and increased temperature;
feeling of heat and increased sweating;
general malaise, weakness, weakness;
feeling of body aches, pain in joints and muscles;
headache;
sleep disorders.

However, there are hidden infections, the symptoms of which are very minor and short-lived (mild itching, burning) or may not appear for several years. These include sexually transmitted infections(chlamydia, ureaplasma, mycoplasma). Wherein hidden infections suppress the immune system and affect other organs, manifesting itself in dysbiosis, arthritis and arthrosis.

When should you urgently call a doctor?

Any viral and bacterial infection requires examination and observation by a doctor. Treatment depends on the detection of a particular pathogen, therefore diagnosis of the disease is a priority. To the brightest signs infectious diseases include:

Pulsating headache without specific localization, vomiting that does not bring relief, hemorrhages on the skin (possible meningitis, encephalitis).
Persistent diffuse headache and dizziness, which is accompanied by sleep disturbance. In this case, painkillers do not help (typhus and typhoid fever are possible)
Sharp pain in the calf muscles, in the lower back (leptospirosis).
Sharp pain in the lower back and vomiting - hemorrhagic fever with renal syndrome. Also, lower back pain, decreased visual acuity, blurred contours of objects, decreased amount of urine, hemorrhages in the sclera mean liver damage.
Loss of appetite, nausea, aversion to smoking, feeling of heaviness in the right hypochondrium, darkening of urine (viral hepatitis).
Profuse vomiting, stomach upsets (diarrhea, dysentery).
Sore throat when swallowing, increased body temperature, dry cough, mucous discharge from the nose, sore throat, purulent or bloody sputum, shortness of breath (acute respiratory infections, sore throat, whooping cough, flu).
Skin rashes in the form of pink spots, spots (5-10 mm in diameter), pinpoint hemorrhages, dense nodules, superficial small blisters filled with cloudy contents (rubella, measles, chicken pox).

Is it possible to prevent infectious diseases?

Limiting contacts. If you notice symptoms of a viral or bacterial infection, you should immediately consult a doctor to prevent the infection from spreading.
Immunization– increasing the body’s resistance to certain pathogens by introducing ready-made immunoglobulins into the body. Vaccination is especially important for young children. Now it is possible to prevent such severe viral diseases as hepatitis, polio, rabies, whooping cough, measles, mumps, and smallpox.
Use of medicationsto prevent infection and reproduction of the pathogen. Necessary when a person travels to areas of possible infection (malaria), to prevent complications (sore throat). However, it is not used to prevent bacterial complications from influenza, other acute respiratory diseases, and viral diseases with skin rashes.
Increasing human resistance to an infectious disease, which includes:

strict adherence to personal hygiene rules;
rational and nutritious nutrition;
taking vitamins;
use of adaptogens;
physical activity (exercise, jogging in the morning);
constant hardening of the body (contrast shower, dousing);
stay in the fresh air (regular walks, ventilation of rooms).

There is an opinion that animals, plants and humans predominate in numbers on planet Earth. But this is actually not the case. There are countless microorganisms (microbes) in the world. And viruses are among the most dangerous. They can cause various diseases in humans and animals. Below is a list of the ten most dangerous viruses for humans.

10. Hantaviruses

Hantaviruses are a genus of viruses that are transmitted to humans through contact with rodents or their waste products. Hantaviruses cause various diseases belonging to such groups of diseases as “hemorrhagic fever with renal syndrome” (mortality on average 12%) and “hantavirus cardiopulmonary syndrome” (mortality up to 36%). The first major outbreak of disease caused by hantaviruses, known as Korean hemorrhagic fever, occurred during the Korean War (1950-1953). Then more than 3,000 American and Korean soldiers felt the effects of a then unknown virus that caused internal bleeding and impaired kidney function. Interestingly, it is this virus that is considered the probable cause of the epidemic in the 16th century that exterminated the Aztec people.

9. Influenza virus

The influenza virus is a virus that causes an acute infectious disease of the respiratory tract in humans. Currently, there are more than 2 thousand of its variants, classified into three serotypes A, B, C. The group of viruses from serotype A, divided into strains (H1N1, H2N2, H3N2, etc.) is the most dangerous for humans and can lead to epidemics and pandemics. Every year, between 250 and 500 thousand people worldwide die from seasonal influenza epidemics (most of them children under 2 years of age and elderly people over 65 years of age).

8. Marburg virus

Marburg virus is a dangerous human virus first described in 1967 during small outbreaks in the German cities of Marburg and Frankfurt. In humans, it causes Marburg hemorrhagic fever (mortality rate 23-50%), which is transmitted through blood, feces, saliva and vomit. The natural reservoir for this virus is sick people, probably rodents and some species of monkeys. Symptoms in the early stages include fever, headache and muscle pain. In the later stages - jaundice, pancreatitis, weight loss, delirium and neuropsychiatric symptoms, bleeding, hypovolemic shock and multiple organ failure, most often the liver. Marburg fever is one of the top ten deadly diseases transmitted from animals.

7. Rotavirus

The sixth most dangerous human virus is Rotavirus, a group of viruses that are the most common cause of acute diarrhea in infants and young children. Transmitted by the fecal-oral route. The disease is usually easy to treat, but kills more than 450,000 children under five worldwide each year, most of whom live in underdeveloped countries.

6. Ebola virus

Ebola virus is a genus of virus that causes Ebola hemorrhagic fever. It was first discovered in 1976 during an outbreak of the disease in the Ebola River basin (hence the name of the virus) in Zaire, DR Congo. It is transmitted through direct contact with the blood, secretions, other fluids and organs of an infected person. Ebola fever is characterized by a sudden increase in body temperature, severe general weakness, muscle pain, headaches, and sore throat. Often accompanied by vomiting, diarrhea, rash, impaired renal and liver function, and in some cases internal and external bleeding. According to the US Centers for Disease Control, in 2015, 30,939 people were infected with Ebola, of whom 12,910 (42%) died.

5. Dengue virus

Dengue virus is one of the most dangerous viruses for humans, causing dengue fever in severe cases, which has a mortality rate of about 50%. The disease is characterized by fever, intoxication, myalgia, arthralgia, rash and swollen lymph nodes. It is found mainly in the countries of South and Southeast Asia, Africa, Oceania and the Caribbean, where about 50 million people are infected annually. The carriers of the virus are sick people, monkeys, mosquitoes and bats.

4. Smallpox virus

Smallpox virus is a complex virus, the causative agent of a highly contagious disease of the same name that affects only humans. This is one of the oldest diseases, the symptoms of which are chills, pain in the sacrum and lower back, rapid increase in body temperature, dizziness, headache, vomiting. On the second day, a rash appears, which eventually turns into purulent blisters. In the 20th century, this virus claimed the lives of 300-500 million people. About US$298 million was spent on the smallpox campaign from 1967 to 1979 (equivalent to US$1.2 billion in 2010). Fortunately, the last known case of infection was reported on October 26, 1977 in the Somali city of Marka.

3. Rabies virus

The rabies virus is a dangerous virus that causes rabies in humans and warm-blooded animals, which causes specific damage to the central nervous system. This disease is transmitted through saliva from the bite of an infected animal. Accompanied by an increase in temperature to 37.2-37.3, poor sleep, patients become aggressive, violent, hallucinations, delirium, a feeling of fear appear, soon paralysis of the eye muscles, lower extremities, paralytic respiratory disorders and death occurs. The first signs of the disease appear late, when destructive processes have already occurred in the brain (swelling, hemorrhage, degradation of nerve cells), which makes treatment almost impossible. To date, only three cases of human recovery without vaccination have been recorded; all others ended in death.

2. Lassa Virus

Lassa virus is a deadly virus that is the causative agent of Lassa fever in humans and primates. The disease was first discovered in 1969 in the Nigerian city of Lassa. It is characterized by a severe course, damage to the respiratory system, kidneys, central nervous system, myocarditis and hemorrhagic syndrome. It is found mainly in West African countries, especially in Sierra Leone, the Republic of Guinea, Nigeria and Liberia, where the annual incidence ranges from 300,000 to 500,000 cases, of which 5 thousand lead to the death of the patient. The natural reservoir of Lassa fever is polymammated rats.

1. AIDS virus

Human immunodeficiency virus (HIV) is the most dangerous human virus, the causative agent of HIV infection/AIDS, which is transmitted through direct contact of mucous membranes or blood with bodily fluid of the patient. During HIV infection, the same person develops new strains (varieties) of the virus, which are mutants, completely different in reproduction speed, capable of initiating and killing certain types of cells. Without medical intervention, the average life expectancy of a person infected with the immunodeficiency virus is 9-11 years. According to 2011 data, 60 million people worldwide have become infected with HIV, of which 25 million have died, and 35 million continue to live with the virus.

10 Hantaviruses

Hantaviruses are a genus of viruses that are transmitted to humans through contact with rodents or their waste products. Hantaviruses cause various diseases belonging to such groups of diseases as “hemorrhagic fever with renal syndrome” (mortality on average 12%) and “hantavirus cardiopulmonary syndrome” (mortality up to 36%). The first major outbreak of disease caused by hantaviruses, known as Korean hemorrhagic fever, occurred during the Korean War (1950–1953). Then more than 3,000 American and Korean soldiers felt the effects of a then unknown virus that caused internal bleeding and impaired kidney function. Interestingly, it is this virus that is considered the likely cause of the epidemic in the 16th century that exterminated the Aztec people.

9 Influenza virus

Influenza virus is a virus that causes an acute infectious disease of the respiratory tract in humans. Currently, there are more than 2 thousand of its variants, classified into three serotypes A, B, C. The group of viruses from serotype A, divided into strains (H1N1, H2N2, H3N2, etc.) is the most dangerous for humans and can lead to epidemics and pandemics. Every year, between 250 and 500 thousand people worldwide die from seasonal influenza epidemics (most of them children under 2 years of age and elderly people over 65 years of age).

8 Marburg virus

7 Rotavirus

Sixth on the list of the most dangerous human viruses is Rotavirus, a group of viruses that are the most common cause of acute diarrhea in infants and young children. Transmitted by the fecal-oral route. The disease is usually easy to treat, but kills more than 450,000 children under five worldwide each year, most of whom live in underdeveloped countries.

6 Ebola virus

5 Dengue virus

Dengue virus is one of the most dangerous biological viruses for humans, causing dengue fever, in severe cases, which has a mortality rate of about 50%. The disease is characterized by fever, intoxication, myalgia, arthralgia, rash and swollen lymph nodes. It is found mainly in the countries of South and Southeast Asia, Africa, Oceania and the Caribbean, where about 50 million people are infected annually. The carriers of the virus are sick people, monkeys, mosquitoes and bats.

4 Smallpox virus

Smallpox virus is a complex virus, the causative agent of a highly contagious disease of the same name that affects only humans. This is one of the oldest diseases, the symptoms of which are chills, pain in the sacrum and lower back, rapid increase in body temperature, dizziness, headache, vomiting. On the second day, a rash appears, which eventually turns into purulent blisters. In the 20th century, this virus claimed the lives of 300–500 million people. About US$298 million was spent on the smallpox campaign from 1967 to 1979 (equivalent to US$1.2 billion in 2010). Fortunately, the last known case of infection was reported on October 26, 1977 in the Somali city of Marka.

3 Rabies virus

The rabies virus is a dangerous virus that causes rabies in humans and warm-blooded animals, which causes specific damage to the central nervous system. This disease is transmitted through saliva from the bite of an infected animal. Accompanied by an increase in temperature to 37.2–37.3, poor sleep, patients become aggressive, violent, hallucinations, delirium, a feeling of fear appear, soon paralysis of the eye muscles, lower extremities, paralytic respiratory disorders and death occurs. The first signs of the disease appear late, when destructive processes have already occurred in the brain (swelling, hemorrhage, degradation of nerve cells), which makes treatment almost impossible. To date, only three cases of human recovery without vaccination have been recorded; all others ended in death.

2 Lassa Virus

1 Human immunodeficiency virus

Human immunodeficiency virus (HIV) is the most dangerous human virus, the causative agent of HIV infection/AIDS, which is transmitted through direct contact of mucous membranes or blood with bodily fluid of the patient. During HIV infection, the same person develops new strains (varieties) of the virus, which are mutants, completely different in reproduction speed, capable of initiating and killing certain types of cells. Without medical intervention, the average life expectancy of a person infected with the immunodeficiency virus is 9–11 years. According to 2011 data, 60 million people have become infected with HIV throughout the world, of which 25 million have died, and 35 million continue to live with the virus.

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

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

To understand the infection process, we can give an analogy with any public institution, which in our case is the human body. Through open doors, various guests - viruses and bacteria - enter the establishment. Some bacteria are intelligent people and do no harm, but some are strictly prohibited from entering: they can provoke a real conflict. As for viruses, these are, for the most part, bandits. You shouldn't expect anything good from them.

There is a security system against unwanted persons outside and inside the establishment - human immunity. Sometimes the immune system does not cope with its tasks, gets tired or is “distracted” by bacteria, allowing dangerous viruses to enter, which immediately begin a raider takeover.

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

What are viruses

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

And he gets there like this:

Airborne, like most respiratory infections
When drinking dirty water, with food, or not following hygiene rules
From mother to unborn child
Contact – in close contact through the skin or mucous membranes
Parenterally - 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 envelope, and only then multiplies. After reproduction, the virus leaves the cell, and the infectious agent spreads along with the blood, continuing total infection. Viruses can suppress the immune system 2.

What are bacteria

A bacterium is a complete, albeit single-celled, organism. It can reproduce through division, which is what it actively does in nature or within humans 3 .

Not all bacteria cause infectious diseases. Some are beneficial and live in the organs of the body. For example, lactic acid or bifidobacteria, which live in the intestines and gastric tract, are actively involved in human life and actually form part of his 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 caused by staphylococci and streptococci)
Gastrointestinal infections (caused by Escherichia coli and enterococci)
Damage to the nervous system (sometimes caused by meningococci)
A number of diseases of the reproductive system, etc.

By multiplying, they spread through the bloodstream, which leads to generalization of the infection and clinical worsening of the patient’s condition. Bacteria can also suppress the immune system, making it harder for the body to resist viruses 3 .

How does a virus differ from a bacterium?

Thus, both viruses and bacteria are capable of infecting the body, causing infection. The key difference between them is in the reproduction mechanism. Viruses cannot reproduce in the external environment, so they need to invade 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 summarize briefly. The differences between a virus and a bacteria are as follows:

Size and form of existence. A virus is the simplest life form, a bacterium is a single-celled living creature.
Life activity. The virus exists only inside the cell and infects it, after which reproduction (cloning) occurs. The bacterium lives a full life, reproducing by division, and the body for it is only a favorable place of existence.
Form of manifestation. Viruses tend to manifest themselves by increased body temperature, general weakness, muscle and joint pain. Bacteria manifest themselves as unhealthy discharge (purulent or as a specific plaque).

Typical viral diseases: ARVI, influenza, herpes, measles and rubella. These 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 one disease together. Such a symbiosis requires special treatment. Examples include: sinusitis, tonsillitis, meningitis, pneumonia and other diseases 5.

Fighting 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 to their path is immunity. Therefore, it is important to strengthen and keep the immune system in a “fighting” state, especially during the cold season and during periods of seasonal diseases.

The immunomodulator IRS®19 will become an assistant on the path 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 to prevent infections in adults and children over 3 months of age. It has been tested many times and has shown excellent results in the fight against infections, including ARVI 6.

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There are no safe diseases

You can die from a cold, a runny nose, or hiccups - the probability is a tiny fraction of a percent, but it exists. The mortality rate from common flu is up to 30% in children under one year of age and the elderly. And if you catch one of the nine most dangerous infections, your chance of recovery will be calculated in fractions of a percent.

1. Creutzfeldt-Jakob disease

1st place among fatal infections went to spongiform encephalopathy, also known as Creutzfeldt-Jakob disease. The infectious agent-pathogen was discovered relatively recently - humanity became acquainted with prion diseases in the mid-twentieth century. Prions are proteins that cause dysfunction and then cell death. Due to their special resistance, they can be transmitted from animal to person through the digestive tract - a person becomes ill by eating a piece of beef with the nervous tissue of an infected cow. The disease lies dormant for years. Then the patient begins to develop personality disorders - he becomes sloppy, grumpy, becomes depressed, his memory suffers, sometimes his vision suffers, even to the point of blindness. Within 8-24 months, dementia develops and the patient dies from brain disorders. The disease is very rare (only 100 people have fallen ill over the past 15 years), but absolutely incurable.

2. HIV

The human immunodeficiency virus has moved from 1st to 2nd place quite recently. It is also classified as a new disease - until the second half of the 20th century, doctors did not know about infectious lesions of the immune system. According to one version, HIV appeared in Africa, passing to humans from chimpanzees. According to another, he escaped from a secret laboratory. In 1983, scientists managed to isolate an infectious agent that causes immune damage. The virus was transmitted from person to person through blood and semen through contact with damaged skin or mucous membrane. At first, people from the “risk group” fell ill with HIV - homosexuals, drug addicts, prostitutes, but as the epidemic grew, cases of infection appeared through blood transfusions, instruments, during childbirth, etc. Over the 30 years of the epidemic, HIV has infected more than 40 million people, of whom about 4 million have already died, and the rest may die if HIV progresses to the AIDS stage - a defeat of the immune system that makes the body defenseless to any infections. The first documented case of recovery was recorded in Berlin - an AIDS patient received a successful bone marrow transplant from an HIV-resistant donor.

3. Rabies

Rabies virus, the causative agent of rabies, takes an honorable 3rd place. Infection occurs through saliva through a bite. The incubation period ranges from 10 days to 1 year. The disease begins with a depressed state, slightly elevated temperature, itching and pain at the bite site. After 1-3 days, an acute phase occurs - rabies, which frightens others. The patient cannot drink; any sudden noise, flash of light, or the sound of flowing water causes convulsions, hallucinations and violent attacks begin. After 1-4 days, the frightening symptoms weaken, but paralysis appears. The patient dies from respiratory failure. A full course of preventive vaccinations reduces the likelihood of disease to hundredths of a percent. However, once symptoms of the disease appear, recovery is almost impossible. With the help of the experimental “Milwaukee Protocol” (immersion in an artificial coma), four children have been saved since 2006.

4. Hemorrhagic fever

This term hides a whole group of tropical infections caused by filoviruses, arboviruses and arenaviruses. Some fevers are transmitted by airborne droplets, some through mosquito bites, some directly through blood, contaminated things, meat and milk of sick animals. All hemorrhagic fevers are characterized by highly resistant infectious carriers and are not destroyed in the external environment. The symptoms at the first stage are similar - high temperature, delirium, pain in muscles and bones, then bleeding from physiological orifices of the body, hemorrhages, and bleeding disorders occur. The liver, heart, and kidneys are often affected; necrosis of the fingers and toes may occur due to impaired blood supply. Mortality ranges from 10-20% for yellow fever (the safest, there is a vaccine, treatable) to 90% for Marburg fever and Ebola (vaccines and treatment do not exist).

5. Plague

Yersinia pestis, the plague bacterium, has long since fallen from its honorary pedestal as the deadliest. During the Great Plague of the 14th century, this infection managed to destroy about a third of the population of Europe; in the 17th century, it wiped out a fifth of London. However, already at the beginning of the 20th century, the Russian doctor Vladimir Khavkin developed the so-called Khavkin vaccine, which protects against the disease. The last large-scale plague epidemic occurred in 1910-11, affecting about 100,000 people in China. In the 21st century, the average number of cases is about 2,500 per year. Symptoms - the appearance of characteristic abscesses (buboes) in the area of the axillary or inguinal lymph nodes, fever, fever, delirium. If modern antibiotics are used, the mortality rate for the uncomplicated form is low, but for the septic or pulmonary form (the latter is also dangerous because of the “plague cloud” around patients, consisting of bacteria released when coughing) is up to 90%.

6. Anthrax

The anthrax bacterium, Bacillus anthracis, was the first pathogenic microorganism to be captured by “germ hunter” Robert Koch in 1876 and identified as the causative agent of the disease. Anthrax is highly contagious, forms special spores that are unusually resistant to external influences - the carcass of a cow that died from the ulcer can poison the soil for several decades. Infection occurs through direct contact with pathogens, and occasionally through the gastrointestinal tract or air contaminated with spores. Up to 98% of the disease is cutaneous, with the appearance of necrotic ulcers. Further recovery or transition of the disease to the intestinal or especially dangerous pulmonary form of the disease is possible, with the occurrence of blood poisoning and pneumonia. The mortality rate for the cutaneous form without treatment is up to 20%, for the pulmonary form - up to 90%, even with treatment.

7. Cholera

The last of the “old guard” of especially dangerous infections, which still causes deadly epidemics - 200,000 patients, more than 3,000 deaths in 2010 in Haiti. The causative agent is Vibrio cholerae. Transmitted through feces, contaminated water and food. Up to 80% of people who have been in contact with the pathogen remain healthy or have a mild form of the disease. But 20% are faced with moderate, severe and fulminant forms of the disease. Symptoms of cholera are painless diarrhea up to 20 times a day, vomiting, convulsions and severe dehydration, leading to death. With full treatment (tetracycline antibiotics and fluoroquinolones, hydration, restoration of electrolyte and salt balance), the chance of death is low; without treatment, mortality reaches 85%.

8. Meningococcal infection

Meningococcus Neisseria meningitidis is the most insidious infectious agent among the especially dangerous ones. The body is affected not only by the pathogen itself, but also by toxins released during the decay of dead bacteria. The carrier is only a person, it is transmitted by airborne droplets, through close contact. Mostly children and people with weakened immune systems fall ill, about 15% of the total number of those in contact. An uncomplicated disease - nasopharyngitis, runny nose, sore throat and fever, without consequences. Meningococcemia is characterized by high fever, rash and hemorrhages, meningitis - septic brain damage, meningoencephalitis - paralysis. Mortality without treatment is up to 70%, with timely started therapy - 5%.

9. Tularemia

It is also known as mouse fever, deer disease, “lesser plague”, etc. Caused by the small gram-negative bacillus Francisella tularensis. Transmitted through the air, through ticks, mosquitoes, contact with patients, food, etc., virulence is close to 100%. The symptoms are similar in appearance to the plague - buboes, lymphadenitis, high fever, pulmonary forms. It is not lethal, but causes long-term impairment and, theoretically, is an ideal basis for the development of bacteriological weapons.