The environment is filled with a huge number of "inhabitants", among which there are various microorganisms: viruses, bacteria, fungi, protozoa. They can live in absolute harmony with a person (non-pathogenic), exist in the body without causing harm under normal conditions, but become more active under the influence of certain factors (conditionally pathogenic) and be dangerous to humans, causing the development of a disease (pathogenic). All these concepts relate to the development of the infectious process. What is an infection, what are its types and features - discussed in the article.
Basic concepts
Infection is a complex of relationships between various organisms, which has a wide range of manifestations - from asymptomatic carriage to the development of the disease. The process appears as a result of the introduction of a microorganism (virus, fungus, bacterium) into a living macroorganism, in response to which a specific defensive reaction occurs on the part of the host.
Features of the infectious process:
- Contagiousness - the ability to quickly spread from a sick person to a he althy one.
- Specificity - a certain microorganism causes a specific disease, which has its characteristic manifestations and localization in cells or tissues.
- Periodicity - each infectious process has periods of its course.
Periods
The concept of infection is also based on the cyclical nature of the pathological process. The presence of periods in development is characteristic of each similar manifestation:
- The incubation period is the time that passes from the moment a microorganism enters the body of a living being until the first clinical signs of the disease appear. This period can last from a few hours to several years.
- The prodromal period is the appearance of a general clinic characteristic of most pathological processes (headache, weakness, fatigue).
- Acute manifestations - the peak of the disease. During this period, specific symptoms of infection develop in the form of rashes, characteristic temperature curves, tissue damage at the local level.
- Reconvalescence is the time when the clinical picture fades and the patient recovers.
Types of infectious processes
To take a closer look at what an infection is, you need to understand what it is. There are a significant number of classifications depending on the origin, course, localization, number of microbial strains, etc.
1. According to the way of penetrationexciters:
- exogenous process - characterized by the penetration of a pathogenic microorganism from the external environment;
- endogenous process - there is an activation of own conditionally pathogenic microflora under the influence of adverse factors.
2. Origin:
- spontaneous process - characterized by the absence of human intervention;
- experimental - the infection was bred artificially in the laboratory.
3. By number of microorganisms:
- monoinfection - caused by one type of pathogen;
- mixed - several types of pathogens are involved.
4. Ordered:
- primary process - newly emerged disease;
- secondary process - accompanied by the addition of an additional infectious pathology against the background of a primary disease.
5. By localization:
- local form - the microorganism is only in the place through which it entered the host organism;
- generalized form - pathogens spread throughout the body with further settling in certain favorite places.
If microbes spread through the bloodstream but do not multiply there, this condition is called viremia (pathogen - virus), bacteremia (bacteria), fungemia (fungi), parasitemia (protozoa). In the case of reproduction of pathogenic microorganisms in the blood, sepsis develops.
6. Downstream:
- acute infection -has a vivid clinical picture and lasts no more than a few weeks;
- chronic infection - characterized by a sluggish course, can last for decades, has exacerbations (relapses).
7. By age:
- "Children's" infections - mainly affect children aged 2 to 10 years (chickenpox, diphtheria, scarlet fever, whooping cough);
- there is no concept of "adult infections" as such, since the children's body is also sensitive to those pathogens that cause the development of the disease in adults.
There are concepts of reinfection and superinfection. In the first case, a person who has fully recovered, after an illness, becomes infected again with the same pathogen. With superinfection, re-infection occurs even in the course of the disease (pathogen strains overlap each other).
Ways to hit
The following pathways of penetration of microorganisms are distinguished, which ensure the transfer of pathogens from the external environment to the host organism:
- fecal-oral (consists of alimentary, water and contact household);
- transmissible (blood) - includes sexual, parenteral and through insect bites;
- aerogenic (air-dust and air-drop);
- contact-sexual, contact-wound.
Most pathogens are characterized by the presence of a specific route of penetration into the macroorganism. If the transmission mechanism is interrupted, the disease may not appear at all or worsen in itsmanifestations.
Localization of the infectious process
Depending on the affected area, the following types of infections are distinguished:
- Intestinal. The pathological process occurs in the gastrointestinal tract, the pathogen penetrates the fecal-oral route. These include salmonellosis, dysentery, rotavirus, typhoid fever.
- Respiratory. The process occurs in the upper and lower respiratory tract, microorganisms "move" in most cases through the air (influenza, adenovirus infection, parainfluenza).
- Outdoor. Pathogens contaminate mucous membranes and skin, causing fungal infections, scabies, microsporia, STDs.
- Blood. The infection enters through the blood, spreading further throughout the body (HIV infection, hepatitis, diseases associated with insect bites).
Intestinal infections
Let's consider the features of pathological processes on the example of one of the groups - intestinal infections. What is an infection that affects the human gastrointestinal tract, and how is it different?
Diseases of the presented group can be caused by pathogens of bacterial, fungal and viral origin. Viral microorganisms that can penetrate into various parts of the intestinal tract are rotaviruses and enteroviruses. They are able to spread not only by the fecal-oral route, but also by airborne droplets, affecting the epithelium of the upper respiratory tract and causing herpes sore throat.
Bacterial diseases (salmonellosis, dysentery) are transmittedexclusively by the fecal-oral route. Infections of fungal origin occur in response to internal changes in the body that occur under the influence of long-term use of antibacterial or hormonal drugs, with immunodeficiency.
Rotaviruses
Rotavirus intestinal infection, the treatment of which should be comprehensive and timely, in principle, like any other disease, accounts for half of the clinical cases of viral intestinal infectious pathologies. An infected person is considered dangerous to society from the end of the incubation period until full recovery.
Rotavirus intestinal infection in children is much more severe than in adults. The stage of acute manifestations is accompanied by the following clinical picture:
- abdominal pain;
- diarrhea (stool is light in color, there may be blood impurities);
- vomiting;
- hyperthermia;
- runny nose;
- inflammatory processes in the throat.
Rotavirus intestinal infection in children in most cases is accompanied by outbreaks of the disease in school and preschool institutions. By the age of 5, most babies have experienced the effects of rotaviruses on themselves. The following infections are not as severe as the first clinical case.
Surgical infection
Most patients requiring surgical intervention are interested in the question of what a surgical-type infection is. This is the same process of interaction of the human body with a pathogenic agent, which only occurs against the background of an operation or requiressurgery to restore function in a specific disease.
Distinguish between acute (purulent, putrefactive, specific, anaerobic) and chronic process (specific, nonspecific).
Depending on the location of the surgical infection, diseases are distinguished:
- soft tissues;
- joints and bones;
- of the brain and its structures;
- abdominal organs;
- thoracic organs;
- pelvic organs;
- individual elements or organs (mammary gland, hand, foot, etc.).
Surgical infections
Currently, the most frequent "guests" of acute purulent processes are:
- staph;
- Pseudomonas aeruginosa;
- enterococcus;
- E. coli;
- streptococcus;
- proteus.
The entrance gates of their penetration are various damage to the mucous membranes and skin, abrasions, bites, scratches, gland ducts (sweat and sebaceous). If a person has chronic foci of accumulation of microorganisms (chronic tonsillitis, rhinitis, caries), then they cause the spread of pathogens throughout the body.
Infection treatment
The basis of getting rid of pathological microflora is etiotropic therapy aimed at eliminating the cause of the disease. Depending on the type of pathogen, the following groups of medicines are used:
- Antibiotics (if the causative agent is a bacterium). Group selectionantibacterial agents and a specific drug are made on the basis of bacteriological examination and determination of the individual sensitivity of the microorganism.
- Antiviral (if the pathogen is a virus). In parallel, they use drugs that strengthen the defenses of the human body.
- Antimycotics (if the causative agent is a fungus).
- Anthelmintic (if the pathogen is a helminth or the simplest).
Treatment of infections in children under 2 years of age is carried out in a hospital to avoid the development of possible complications.
Conclusion
After the occurrence of a disease that has a specific pathogen, the specialist differentiates and determines the need for hospitalization of the patient. Be sure to indicate the specific name of the disease in the diagnosis, and not just the word "infection". The case history, which is taken for inpatient treatment, contains all the data on the stages of diagnosis and treatment of a specific infectious process. If there is no need to hospitalize the patient, all such information is recorded in the outpatient card.
