What viruses can be in the computer. Types of computer viruses and how they are dangerous. Virus tests: what infections they detect

Questions related to what computer viruses are and their names, what are the ways of their penetration into the system and the impact on computers or user data, ordinary users usually do not care at all until a certain moment. But that's when operating system or the programs installed in it begin to behave completely inadequately, many begin to look for answers, but often it is too late. But there are many cases when an OS (most often this refers to Windows systems) is not something that does not work correctly, but it may even be blocked or completely fail. Let's try to figure out what computer viruses are. The names of the main threats will also be given, but it should be said right away that the classification presented below is purely conditional, since today there is no unified structured system for recognizing computer threats and classifying them into a specific class. And this is mainly due to the fact that more and more often there are mixed types of threats that are simply impossible to include in any particular class.

The simplest classification of computer threats

So, to begin with, let's consider the simplest division of threats into main types. It is believed that viruses and worms are the main ones at the moment.

The difference between these two large categories is that the former penetrate computers through malicious files and inject their own codes into programs, while the latter can infect files of a specific type (for example, all EXE-format objects, office documents or multimedia content). This division does not allow us to clearly understand the complete difference between some types of threats, therefore, for a more detailed classification, additional criteria are used, which will be discussed below.

Ways of introducing threats to computers

But let's leave the names of computer viruses aside for now, and pay special attention to figuring out how exactly threats can penetrate user computers. Most often, experts identify several main loopholes here:

• vulnerability of the operating system and browsers used for web surfing;
• removable media;
• networks;
• inadequate quality of antivirus software;
• stupidity or carelessness of the user himself.

As far as operating systems are concerned, it is naive to believe that viruses only affect legacy DOS systems or Windows. Until recently, it was believed that virus threats do not work on Apple and UNIX-like operating systems, including Linux. However, now an absolutely confirmed fact is the impact of viruses and malicious codes with the disabling of the same "iPhones" running on iOS, or Android devices, the operating systems of which are based on the Linux kernel.

With browsers, I think, and so everything is clear, because when you visit unreliable resources that may contain threats, using the same Internet Explorer, viruses can be typed in absolutely elementary, and not only when downloading some files, but also simply when entering a site that can automatically execute ActiveX scripts.

The quality of antiviruses can also play a cruel joke with the user, since some of the widely advertised and praised antiviruses are unable to fully protect the computer and user information from threats. In this case, a striking example can be called viral advertising applets, many of which even have security certificates.

On removable media, threats are most often present in the form of autorun files (Autorun.inf), and when connected to a PC or laptop, computer viruses infect the device exactly when it is triggered.

As for the inattention of users, this most often manifests itself when installing programs downloaded from dubious sources (for example, from torrent trackers), when they do not pay attention to the offers to install the accompanying allegedly partner software, which in fact turns out to be an adware or spyware virus type. Well, we are not talking about ignoring the warnings of antiviruses that may appear when trying to go to virus-containing sites on the Internet.

In addition, when computers are connected in a network, threats can be transmitted from one infected terminal to all others precisely through gaps in a network that does not have an antivirus or firewall.

Signs of a computer system infection

Due to the impact, which may not appear immediately, the system decelerates with an unreasonably high load on system resources (CPU, RAM or hDD).

Sometimes stop working installed applications, or driver errors occur, which can lead to the appearance of the notorious blue screens... Finally, the browser can be flooded with advertisements, but the saddest thing is that sometimes some files are locked or encrypted, the operating system stops loading, and only helps in this case full formatting disk with OS reinstallation.

Computer viruses: types and their names in the main classes

Now let's move on to a more advanced classification. The main computer viruses are generally as follows:

• file viruses contained in an infected file and activated only when it is launched by the user himself or accessed by the system / program;
• boot viruses that embed their own codes or startup commands in the autostart of the system or removable media;
• macro viruses contained on websites on the Internet or sent via e-mail in the form of scripts that are executed exclusively in installed programsah or superstructures;
• network viruses.

Again, this distribution can also be called conditional, since today there are mixed types of threats like file-boot or network macro viruses.

The main types of computer viruses: names and descriptions of the impact

Finally, the most accurate description of threats can be found in the following classification:

• trojan horses that infiltrate computers under the guise of safe legal software that can gain access to installed programs and user data, transfer control of the computer, or "drain" information to cybercriminals;
• spyware stealing extremely important confidential information or tracking user actions on the computer;
• spy-related keyloggers that monitor keyboard input;
• extortionists (winlockers) blocking the system and requiring money transfer for unblocking;
• cryptors fully encrypting user or system files a certain type;
• vandals seeking to inflict maximum damage on the operating system in terms of loss of performance;
• hybrid rootkits that simultaneously track user actions and interfere with the system according to a specific scenario;
• botnets that turn a computer into a kind of zombie and use its resources to carry out DDoS attacks or influence other terminals via networks or the Internet.

In general, it should be said that these are only the main names of computer viruses, since they are replenished almost daily with more and more new copies that cannot be attributed to any of the known categories.

Functioning algorithms

We figured out a little about infection with computer viruses and their types. However, we should dwell on the classification of threats in terms of the algorithms used by them. For this, a division into resident and non-resident viruses has been adopted.

Resident threats are programs that load their executable components directly into RAM and can be constantly active from the moment the operating system is loaded until the computer is turned off. Non-resident threats usually have a limited lifetime, although they can also load their small resident portion into RAM, but this usually does not happen.

A striking example of residents are all kinds of macro viruses in the form of executable scripts, and many of them, in addition to everything, also use stealth technology, which allows them to remain unnoticed in the system, replacing the elements that the operating system accesses with its own processes.

Another distribution of the names of computer viruses by class is associated with self-encryption and polymorphism. Encryption in a sense resembles stealth disguise, but it is capable of constantly changing, which is very high degree makes it difficult to determine by protective equipment.

Some of these threats may not contain any malicious code signatures at all, which could at least with some degree of probability be classified as viruses. But the most dangerous threats very often even use some non-standard camouflage methods that allow them to hide deep in the kernel of the operating system, where no antivirus can reach.

Destructive properties of viruses

Despite their names, computer viruses of different classes are very similar to each other. But in order to classify them according to the degree of impact, it is customary to distinguish four categories:

• harmless (joke programs);
• non-hazardous (limited only by the consumption of system resources);
• dangerous (leading to very serious failures in the OS);
• very dangerous (completely disabling the system or destroying data stored on the computer).

Basic methods of fighting computer threats

Naturally, as the first method for detecting all kinds of known threats or initializing suspicious objects, it is recommended to use standard antiviruses that have signature and behavioral analysis modules, as well as Anti-Stealth modules.

Antiviruses with the ability to send suspicious objects for analysis to the "cloud" or "sandbox" also look good in this respect. But you cannot absolutely rely on such tools alone.

Tips for removing some ad viruses yourself

Adware viruses, of which there have been a lot of things lately, can be removed by yourself. As a rule, such threats are not particularly masked in the system, but you can find them either in the list of installed programs, or among panels or browser extensions.

To neutralize these threats, it is enough to remove the main application, clean the registry and residual files in Explorer, change in browsers search engine and the initial page, after which, finally, correct the path to the executable file of the browser launch in the properties of the shortcut, removing all unnecessary links and postscripts after specifying its name with the extension. Uninstaller programs that automatically clean up leftovers help a lot in terms of removal.

Outcome

That is, in short, everything related to the names of computer viruses, their distribution into classes, groups and categories, based on different criteria. As additional recommendations you can advise the following:

• install only powerful antivirus programs, even if they are shareware (many of these programs can be permanently activated for 30 days or more using special free codes);
• do not ignore antivirus warnings when working with the Internet;
• do not visit obviously questionable sites and do not download files from them;
• be attentive to suggestions for installing additional software;
• check the contents of removable media before performing any action with them;
• perform a preventive check at least once a month using portable utilities.

Computer viruses are specially designed malicious code that has the ability to copy, make its own copy, and inject it into programs or files stored on the computer.

How to detect a virus on your computer

The following signs may indicate the presence of infection

• decreased system performance
• extraneous phrases and images appearing on the desktop
• various video effects, disappearance of inscriptions on the screen, mute
• errors when starting programs and applications

One or more of these signs indicate that the removal of encoders or other malware is required. Depending on the type of virus, there are several ways of infection.

What are computer viruses

The most common virus programs are encoders, Trojans and worms. Even an experienced user can miss the point of infecting their computer. Modern antivirus programs also fail to fully protect your PC from the threat of malware infection. They also cannot guarantee the complete destruction of all traces of viruses. Specialists using special utilities can clean up the tails.

Virus code able to inject itself into a driver file, files or sectors of the boot disk. When an infected application is launched, the virus program performs the actions first, after which the main file starts working. Therefore, it is important to remove the encoder in time.

Trojan horse - these are viruses that are embedded in other programs and open access to the infected computer. The Trojan cannot spread by itself. It enters the computer from the Internet through downloaded applications. The infected computer starts to freeze, shut down without apparent reasons, and one day it may not turn on at all. Therefore, the Trojan must be removed as quickly as possible.

Worm distributed in the system without user intervention. Most often, such viruses get to the user's computer through e-mail. Therefore, you should not open letters and download information from unknown persons. Once in the system, the worm starts searching for any information with email data. These can be address books, or saved pages from the Internet. Using the information it finds, the worm virus begins to use it to forward infected messages, replacing the data in the sender's field in such a way that it looks like ordinary letters from a known address and does not arouse suspicion. These viruses may not cause significant damage to your computer, but they will degrade performance.

If a virus program is activated during the startup of the operating system, it begins to fully control not only the startup, but also the operation of the OS. Consequently, all operations will be aimed at prolonging the existence of the virus.

Typically, a virus is detected at a stage when many files have already been infected. The damage in this case can be very significant.

How to neutralize a virus in a computer

The virus removal procedure can take a lot of time and effort. It all depends on the degree of infection of the system and the type of virus. For example, removing a Trojan can take up to several hours.

In the case when the virus has already begun to multiply and infect various system files, any delay can be disastrous for the operating system and for all information stored on the computer.

You can get rid of viruses using a special antivirus program. If you cannot remove viruses yourself, it is best to contact a specialist.

For comfortable and safe work at the computer, you must have a minimum of knowledge on ensuring the protection of personal data. To do this, first of all, you need to know what a computer virus is. You also need to remember that the best way to deal with it is antivirus software.

The definition of a computer virus reads as follows: "A computer virus is software with the ability to copy itself, be embedded in system code and other software products, as well as cause irreparable damage to the hardware of a computer and information stored on its media.

The main purpose of any virus is to harm, steal information, or monitor your computer. Other actions of computer viruses are also traced. The propensity to reproduce allows for maximum damage. The fact that viruses are capable of multiplying not only within the local machine, but also travel over networks, including global ones, suggests that outbreaks of computer viruses are possible.

Phases and states typical of computer viruses

• Passive existence: in this state, the virus is written to the hard disk, but does not take any action until the conditions specified by the programmer are met.
• Reproduction: a condition in which a virus creates an uncountable number of copies of itself and resides on a computer's hard drive, and is also transmitted to the local network with service packages.
• Active existence: in this mode, the virus begins to fulfill its purpose - to destroy, copy data, artificially occupy disk space and consume RAM.

How computer viruses appeared

The history of computer viruses officially begins in 1981. Computing technology was in its infancy. Then no one knew what a computer virus was. Richard Skrenta wrote the first bootable virus for the Apple II computer. He was comparatively harmless and displayed a poem. Later, viruses for MS-DOS began to appear. In 1987, three virus epidemics were recorded at once. This was facilitated by the entry into the market of a relatively inexpensive IBM computer and the growth of computerization as a whole around the globe.

The first epidemic was triggered by the Brain malware, or "Pakistani virus". It was developed by the Alvi brothers to punish users using hacked versions of their software... The brothers did not expect the virus to spread outside Pakistan, but it did, and the Brain virus infected computers around the world.

A second epidemic occurred at Lehigh University in the United States of America, and several hundred diskettes in the university's computer center library were destroyed. The epidemic was of an average scale for those times, and the virus affected only 4 thousand computers.

The third virus, Jerusalem, originated in several countries around the world. The virus destroyed all files as soon as they were launched. Among the epidemics of 1987-1988, this was the largest.

1990 was the starting point for an active fight against viruses. By this time, many programs were already written that harm computers, but until the 90s this was not a big problem.

In 1995, complex viruses began to emerge, and an incident occurred in which all Windows 95 beta discs became infected with viruses.

Today, the expression "computer virus" has become commonplace, and the malware industry is growing rapidly. New viruses appear every day: computer, telephone, and now viruses for watches. In spite of them, various companies produce security systems, but computers are still infected in all corners of the world.

Ebola computer virus

The computer virus "Ebola" is very relevant today. Hackers send it by e-mail under the guise of names of well-known companies. The virus infects software installed on computers and is capable of very quickly deleting everything that is installed on the machine. In addition, it can reproduce, including by local network... Thus, "Ebola" is considered one of the most dangerous objects today.

Classification of malware

Computer viruses are classified according to various criteria. Depending on their behavior, they were conditionally divided into 6 categories: according to their environment, according to the peculiarities of the structure of the code, according to the method of infecting the computer, according to integrity, according to their capabilities, and in addition there is a category of unclassified viruses.

According to the habitat, there are the following types of computer viruses:

• Network - these viruses spread over local or global networks, infecting a huge number of computers around the world.
• File - are embedded in a file, infecting it. The danger begins at the moment the infected file is executed.
• Boot - are being introduced into boot sector hard disk and start execution when the system boots.

According to the features of the code structure, viruses are divided into:

According to the method of infecting the code, viruses are divided into two groups:

• Resident - malwarethat infect the RAM.
• Non-resident - viruses that do not infect RAM.

By integrity, they are divided into:

• Distributed - programs, divided into several files, but having a script for the sequence of their execution.
• Holistic - single block programs that are performed by a direct algorithm.

According to their capabilities, viruses are divided into the following four categories:

• Harmless - types of computer viruses that can slow down your computer by multiplying and absorbing free space on your hard drive.
• Non-hazardous - viruses that slow down your computer take up a significant amount random access memory and create sound and graphic effects.
• Dangerous - viruses that can lead to serious system failures, from freezing the computer to the destruction of the operating system.
• Very dangerous - viruses that can erase system informationand also lead to physical destruction of the computer by disrupting the power distribution of the main components.

Various viruses that do not fall under the general classification:

• Network worms - viruses that calculate the addresses of available computers on the network and multiply. As a rule, they are classified as harmless viruses.
• Trojans, or Trojans.These types of computer viruses got their name in honor of the famous Trojan horse. These viruses disguise themselves as useful programs... They are designed mainly to steal confidential information, but there are also varieties of more dangerous representatives of malware.

How to detect a virus on your computer?

Viruses are able to be invisible, but at the same time perform unwanted actions on the computer. In one case, the presence of a virus is almost impossible to detect, while in another, the user observes a number of signs of computer infection.

For those who do not know what a computer virus is, the following computer actions should cause suspicion of a danger:

• The computer started to run slower. Moreover, the slowdown is more than significant.
• The appearance of files that the user did not create. Particular attention should be paid to files that have a character set or an unknown extension instead of an adequate name.
• A suspicious increase in the occupied area of \u200b\u200bRAM.
• Spontaneous shutdown and restart of the computer, its non-standard behavior, screen blinking.
• Inability to download programs.
• Unexpected errors and crash messages.

All these signs indicate that the computer is most likely infected, and an urgent need to scan it for files with malicious code. There is only one way to check your computer for viruses - antivirus software.

Antivirus programs, or antiviruses, are software packages that have extensive databases of computer viruses and perform a thorough scan of the hard disk for familiar files or code. Antivirus software can disinfect, delete, or isolate the file in a designated area.

Ways and methods of protection against malware

Protection against computer viruses is based on technical and organizational methods. Technical methods are aimed at using means of preventing virus threats: antiviruses, brandwalls, antispam and, of course, timely updating of the operating system. Organizational - methods that describe the correct behavior of the user at the computer in terms of information security.

Technical methods prevent viruses from entering the computer through software.

Antivirus - control the file system, tirelessly check and hunt for traces malicious code... The firewall is designed to control information coming through network channels and block unwanted packets.
The firewall allows you to prohibit a certain type of connection based on various criteria: ports, protocols, addresses and actions.

Antispam - control the receipt of spam, and when a suspicious message arrives at the mail client, they block the execution of attached files until the user enforces them. There is an opinion that antispam is the most ineffective way of fighting, but every day they block tens of millions of letters with embedded viruses.

Operating system update - the process by which developers fix errors and shortcomings in the operation of the OS, which are used by programmers to write viruses.

Organizational methods describe the rules for working with a personal computer, processing information, launching and using software, based on four basic principles:

1. Run and open only those documents and files that come from reliable sources, and in the security of which there is firm confidence. In this case, the user assumes responsibility for launching this or that program.
2. Check all incoming information from any external sources, be it the Internet, an optical disk or a flash drive.
3. Always keep the anti-virus database and the version of the shell software for catching and eliminating threats up to date. This is due to the fact that anti-virus software developers are constantly improving their products, relying on the emergence of new viruses;
4. Always agree with the offers of anti-virus programs to check the flash drive or hard drive connected to the computer.

With the advent of viruses, programs began to appear that allow them to find and neutralize them. New viruses appear in the world every day. Computer products to fix them are updated several times a day to stay current. So, without stopping, there is a constant struggle against computer viruses.

Today the choice of antivirus programs is very large. New offers appear on the market every now and then, and the most diverse: from full-fledged software systems to small subprograms focused on only one type of viruses. You can find security solutions that are free or with a paid term license.

Antiviruses store in their signature databases extracts from the code of a huge amount of dangerous computer systems objects and during the scan they compare the codes of documents and executable files with their base. If a match is found, the antivirus will inform the user about it and offer one of the security options.

Computer viruses and antivirus programs are integral parts of each other. There is an opinion that for the sake of commercial gain, antivirus programs develop dangerous objects on their own.

Antivirus software utilities are divided into several types:

• Detector programs. Designed to search for objects infected with one of the currently known computer viruses. Usually, detectors only look for infected files, but in some cases they are capable of treating them.
• Auditor programs - these programs remember the state file system, and after a while the changes are checked and verified. If the data does not match, the program checks whether the suspicious file has been edited by the user. If the scan is negative, the user will receive a message about possible infection of the object.
• Healing programs - designed to treat programs and entire hard drives.
• Filters - check information coming to the computer from the outside and deny access to suspicious files. As a rule, they display a request to the user. Filters are already being implemented in all modern browsers in order to find a computer virus in time. This is a very effective solution, taking into account the current level of development of the Internet.

The largest anti-virus complexes contain all the utilities that are combined into one large defense mechanism. The outstanding representatives of anti-virus software today are: Kaspersky Anti-Virus, Eset NOD32, Dr.Web, Norton Anti-Virus, Avira Antivir and Avast.

These programs have all the basic capabilities to have the right to be called security software systems. Some of them have extremely limited free versions, and some are offered only for cash rewards.

Varieties of antivirus programs

There are anti-viruses for home computers, office networks, file servers, and network gateways. Each of them can find and remove viruses, but the main focus is on different versions such programs are made for their intended purpose. The most complete functionality, of course, is provided by antivirus software for the home, which has to perform tasks to protect all possible vulnerabilities.

What to do if you suspect a computer infection?

If the user thinks that the computer is infected with a virus, first of all, do not panic, but strictly follow the following sequence of actions:

• Close all programs and files with which the user is currently working.
• Run the anti-virus program (if the program is not installed, install it).
• Find the full check function and run.
• After the scan is finished, the antivirus will offer the user several options for actions with the detected malicious objects: files - disinfect, remove malicious programs, what is not removed - quarantine.
• It is advisable to strictly follow the recommendations of antivirus software.
• After cleaning is complete, restart the scan.

If the antivirus did not find a single threat during the scan, it means that the non-standard operation of the computer is caused by malfunctions in the PC hardware or internal errors of the operating system, which also happens quite often, especially if the operating system is rarely updated.

Viruses can cause a wide variety of diseases, depending on the type of infection and the characteristics of the infected tissue. What viruses do humans have? There are a lot of them, and throughout their lives, people in one way or another come into contact with most infectious agents. The diseases they cause range from relatively easy to carry to deadly. The most common viruses in the world that lead to colds, flu, and hepatitis.

Viruses and colds

The common cold (as they call it in everyday life such as flu, SARS, laryngitis, pharyngitis) remains one of the most common human ailments. In the United States alone, about a billion cases of ARVI are recorded every year. Viral infection the mucous membrane of the nasal passages leads to a runny nose, watery eyes, sore throat and sneezing. The course of the disease lasts from one to two weeks. According to statistics, over 200 of the known strains can cause colds. What types of viruses are the most common causative agents of ARVI? These are various rhinoviruses, adenovirus, coronavirus, Coxsackie virus, echovirus, enterovirus, orthomyxovirus, paramyxovirus and

Flu virus

Influenza is caused by three types of microorganisms. Types A and B lead to seasonal infections, characteristic of the period beginning in late autumn and ending in early spring. Infections with the type C virus are less common and most often cause mild disease. The most common flu symptoms include body aches, fever, tiredness, headache, sore throat, dry cough, and nasal congestion. Influenza shots provide protection against type A and B viral infections.

Intestinal viruses

What viruses are in the digestive system and what are they characteristic signs? Microorganisms of this type invade the tissues of the stomach and intestines, causing viral gastroenteritis. Symptoms common to the disease include abdominal pain, colic, diarrhea, nausea, and vomiting. Rotavirus is a common cause of gastroenteritis in young children, including infants. This infection manifests itself in the form of fever, vomiting, and watery diarrhea. Norovirus is an equally common causative agent of infectious diseases that affects both children and adults. However, in younger patients, diarrhea is almost always predominant, while in adults, persistent vomiting is more common. Other known enteric viruses include strains of adenovirus, sapovirus, and astrovirus.

Hepatitis viruses

The causative agents of this type of infection affect the liver, initiating inflammatory processes. Science knows five different viruses that cause hepatitis; they were named based on the letters of the Latin alphabet from A to E. If you are interested in what kind of hepatitis viruses are in developed countries, then, according to statistical studies, types A, B and C prevail in countries with developed infrastructure and medicine. The hepatitis A virus penetrates into the body when digesting food or water contaminated with feces. It causes one brief episode of hepatitis. Type B strains can cause acute or chronic liver infections. Microorganisms are found in blood and semen. The most common cases of hepatitis B infection include sexual intercourse, sharing the same syringes while using drugs, and mother-to-child transmission during pregnancy and childbirth. The type C virus spreads through contact with the patient's blood. Multiple use of syringes by different people while using drugs is the most common mode of transmission. Hepatitis C is usually chronic, but adequate treatment can often improve the course of the disease.

Other viruses

What are the viruses in humans besides the above? If you print a complete list of titles, you will have to publish several volumes of the list. Moreover: every year scientists discover new types, hitherto unknown. Some strains are very rare, but they are very dangerous due to their potential lethality. These are, for example, the Ebola or rabies viruses. Other microorganisms are quite common and are the root cause of a huge number of diseases. For those who are interested in what types of viruses a person has, it is enough to open any popular medical reference book. So, a clear example of a common type of infection is herpes viruses that cause simple (bubble) herpes on the lips, herpes of the genitals, infectious mononucleosis, chickenpox, shingles and many other ailments. The human papillomavirus causes not only the appearance of common warts on the skin, but also the development of cervical cancer.

What kind of viruses do people have recently? Infections of the newest types - HIV, acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS coronavirus) - remain a serious problem, as there is currently no truly effective treatment for these diseases.

Diagnostics

The diagnosis of a viral infection is mainly based on an initial physical examination and an analysis of the medical history. For example, a disease such as the flu is fairly easy to recognize and most people are familiar with its manifestations. Detection of some other infections, however, may require additional diagnostic studies.

Diagnostic options for viral infection

Since the answer to the question of what viruses are in humans implies thousands of answers, sometimes it is not enough just to examine the patient and study his medical history. In such cases, doctors order one or more of the following tests:

• blood tests to check for antibodies to viruses or to directly detect antigens;
• cultivation of blood components, body fluids and other materials taken from the affected area;
• lumbar puncture for analysis of cerebrospinal fluid;
• polymerase chain reaction technique to create multiple copies of viral genetic material for faster and more accurate identification of the virus;
• magnetic resonance imaging to detect inflammation in the temporal lobes of the brain.

Symptoms

What viruses do humans have? The list is incredibly long, but the symptoms of many infections can be categorized into a single list. For example, signs of a virus infection may include:

• increased body temperature;
• muscle pain;
• cough;
• sneezing;
• runny nose;
• chills;
• diarrhea;
• vomiting;
• skin rash;
• feeling of weakness.

More severe symptoms appear as follows:

• neck stiffness;
• dehydration;
• convulsions;
• paralysis of the limbs;
• loss of orientation in space;
• back pain;
• loss of sensitivity;
• disruption of the bladder and intestines;
• drowsiness, which may progress to a coma or death.

Infection: Viral or Bacterial?

What viruses do humans have? The names are unlikely to tell a layman, but one should distinguish between viral and bacterial infections.

Infections of both types are the reasons for the deterioration of health and the development of various diseases. However, there is a difference between the two. A viral infection, as its name suggests, begins with exposure of the body to a virus - a tiny intracellular agent that is even smaller than a bacterium. In addition, it is in a protective shell, which means it is more difficult to destroy. The virus enters a living cell and integrates its genome into its genetic apparatus. Such infectious agents are non-cellular particles and require foreign cells to reproduce. If you are wondering what viruses are, the names that you find in this article will most likely point you to the main areas of infection. These are the nose, throat and upper respiratory tract. Virus strains can cause both the common cold and AIDS.

To initiate a bacterial infection, the pathogenic bacterium must gain access to the body through contaminated water, cuts on the skin, or contact with an infected person or contaminated objects. One of the fundamental differences between the two types of infections is that bacteria can enter the body through contact with inanimate objects, including doorknobs and table surfaces, but viruses cannot. Another difference is that nature is a cell and multiplies by division, while a virus dies without a host. Most often, bacteria enter the body through the respiratory tract or the gastrointestinal tract. Some bacterial infections are contagious (like strep throat, strep throat).

Cause of viral infection

The question of what viruses are in humans is especially acute because the cells of the human body are susceptible to them. When exposed to viral particles, the immune system tries to destroy the source of danger and remove foreign strains from the body.