Infection (from the Latin. Inficio, infeci, infectum "infect") - the infection of living organisms with microorganisms ( bacteria , fungi , protozoa ). Infections can also include infections by viruses , prions , rickettsiae , mycoplasmas , proteins , vibrioes , parasites , insects, and arthropods (very rarely). The term means various types of interaction of alien microorganisms with the human body (in medicine), animals (in zootechnics, veterinary medicine), plants (in agronomy).
The term was introduced into medicine Jirolamo Fracastero In 1546. [one]
The science of infection is called infectology and studies the infectious process , infectious disease , infectious pathology resulting from the bodyβs competitive interaction with pathogenic or opportunistic pathogens (infectious agents), and develops methods for diagnosing, treating and preventing infectious diseases. Infectology as a system of medical science is connected or affects in one way or another all other branches of medicine.
Damages of organs and systems (infectious-inflammatory processes: -yes ) caused by infectology - often should be differentiated from other disciplines - systemic. as it progresses, with toxicology , oncology , hematology ( secondary immunodeficiencies in radiation sickness , leukemia , lesions of the thymus , spleen and bone marrow , in case of vitamin deficiency: beriberi , pellagrara , night blindness ) and endocrinology (secondary infectious complications in sugar diabetes , hypothyroidism ), metabolic syndromes such as uremia , liver failure , liver cirrhosis , multiple organ failure .
General infectology is often differentiated from common diseases and local inflammatory processes (tonsillitis, otitis, sinusitis) from septic surgery (phlegmon, empyema, abses) and gangreous-necrotic surgery (lung gangrene / pneumonia, decurable ulcer) they give.
Conditions, pathologies and diseases, infectious-inflammatory processes often differentiate with toxic processes, pathologies and conditions (methods of detoxification and detoxification of the body often overlap), with hematological (hematogenous immunodeficiencies, aplastic anemia, infectious complications in hemablastosis), diseases caused by metabolic disorders , with endocrine (metabolic diarrhea with pancreatic fermentopathies , uremic enteritis, secondary metabolic immunodeficiencies on the background of renal oh, liver failure, on the background of diabetes mellitus and its infectious complications, vitamin deficiency: scurvy) and oncology (the last version of the differential diagnosis is the most often difficult task in modern medicine, but these errors can cost the life of the patient).
Most often, the gastrointestinal forms of acute infections should be differentiated from abdominal or coloproctorectal in the form of acute poisoning. Intoxication of infectious genesis should be differentiated from intoxication of non-infectious genesis β toxic (in foodborne toxicoinfections , botulism , infectious-toxic shock ), oncologic (due to the similarity in the propensity to metastasize some infectious pathogens and their abilities to produce tumor-like symptoms), and in some cases, to start a tumor-like symptom), and in some cases, trigger some of the infectious pathogens and their abilities to produce tumor-like symptoms), and in some cases, trigger some symptoms. carcinogenic processes, and various metabolic syndromes.
Surgical complications usually are extensions of unfavorable course of acute or chronic infection, its generality, as in sepsis , tetanus and septicemia , bakterimii , septipkokemii or if the pathogen is, for example, the tendency to abscess formation (particularly amebiazny liver abscess , cyst , abscessed complications of measles, mumps, streptococcal and staphylococcal infections, erysipelas). Infectology is most closely associated with allergology (assisting in the diagnosis of infections with skin tests), immunology (assisting in diagnosis with ELISA , CSC ), toxicology , pulmonology , gastroenterology , neurology and otolaryngology , as well as maxillofacial surgery (in general infectious practice - most often affected systems from these areas of medicine). Infectology has several sub-sectors that deal with relevant infections: transmission and anthropozoonosis : parasitology - mycology , protozoology , pro-histology , helminthology , rabiology ; viral - virology , bacterial - bacteriology , specific: phthisiology and venereology . Epidemiology was one of the directions of infectiology and in its classical form was associated with it, dealing with issues of the epidemic process area - the spread of infectious pathogens. Microbiology is studying the pathogenic properties of living organisms. Hygiene , antisepsis , asepsis and vaccination deal with measures to prevent and curb the spread of infectious diseases and the formation of pandemics in endemic , and more often, in the era of globalization, climate collapses and global warming - in non-endemic regions.
Types of infections
Infection can develop in different directions and take different forms. The form of infection depends on the ratio of pathogenicity of the microorganism, the factors protecting the macroorganism from infection and environmental factors.
Generalized infection - an infection in which pathogens spread mainly lymph-hematogenous through the entire macro-organism.
Local infection - local damage to body tissues under the action of pathogenic infecto-gene factors. Local process usually occurs at the site of microbe penetration into tissues and is usually characterized by the development of a local inflammatory reaction. Local infections include sore throats , boils , diphtheria , erysipelas , etc. In some cases, a local infection can become common. In some cases, a local infection, from an infectious disease specialist, can go into surgical practice or into a specialist labor, depending on the affected organs, and on the degree of chronicity of the process ( otolaryngologist - angina , urologist - prostatitis , osteomyelitis , periodontitis - maxillofacial surgeon , lung abscess , lung gangrene - thoracic surgeon , rheumatoid arthritis - rheumatologist , meningoencephalitis , ganglia , arachnoiditis - neurologist , vasculitis - vascular surgeon , nephritis , cystitis , pyelonephritis - nephrologist , pneumonia , bronchitis , pleuritis - Pulmo nology , gastroenteritis , hepatitis - gastroenterologist , peritonitis - abdominal surgery , appendicitis , colitis - koloprorektalny surgeon)
A common infection is the penetration of microorganisms into the blood and their spread throughout the body. Having penetrated into the tissues of the body, the microbe multiplies at the site of penetration, and then enters the blood . Such a development mechanism is characteristic of influenza , salmonellosis , typhus , syphilis , some forms of tuberculosis , viral hepatitis , etc.
Latent infection - a condition in which the microorganism that lives and multiplies in the tissues of the body, does not cause any symptoms (chronic gonorrhea , chronic salmonellosis, etc.).
Intercurrent infection is an infection that arises for the second time to an existing one, or to an existing disease, for example, in case of diabetes mellitus, or renal-hepatic insufficiency. It is one type of immunodeficiency.
Manifest infection - an infection with clear specific clinical signs.
Focal infection
Infection arising as a result of inflammation of an organ, accompanied by the destruction of tissues.
Stages of Infectious Diseases
The incubation period - [from the Latin. incubatio "incubation chicks"]. Usually between the penetration of an infectious agent into the body and the manifestation of clinical signs there is a period of time defined for each disease - an incubation period that is characteristic only for exogenous infections. During this period, the pathogen multiplies, there is an accumulation of both the pathogen and the toxins secreted by it up to a certain threshold value, for which the body begins to respond with clinically pronounced reactions. The duration of the incubation period can vary from several hours and days to several years.
Prodromal period - [from ancient Greek ΟΟΟΞ΄ΟΞΏΞΌΞΏΟ "running ahead, preceding"]. As a rule, the initial clinical manifestations do not carry any pathognomonic [from ancient Greek]. ΟΞ¬ΞΈΞΏΟ "disease" + Ξ³Ξ½ΟΞΌΟΞ½ "interpreter, caretaker, norm, rule"] for a specific infection of symptoms. Usual weakness, headache, feeling of weakness. This stage of the infectious disease is called the prodromal period, or the βprecursor stageβ. Its duration does not exceed 24-48 hours.
The period of development of the disease - during this phase, features of the individuality of the disease or signs common to many infectious processes (fever, inflammatory changes, etc.) appear. In the clinically expressed phase, it is possible to distinguish the stages of increasing symptoms (stadium incrementum), the heyday of the disease (stadium acme) and the extinction of manifestations (stadium decrementum).
Reconvalescence - [from lat. re- , repeated action, + convalescentia , recovery]. The recovery period, or recovery, as the final period of an infectious disease can be fast (crisis) or slow (lysis), and also characterized by a transition to a chronic condition. In favorable cases, the clinical manifestations usually disappear faster than normalization of morphological disorders of organs and tissues and complete removal of the pathogen from the body occurs. Recovery may be complete or accompanied by the development of complications (for example, on the part of the CNS, the musculoskeletal system, or the cardiovascular system). The period of the final removal of the infectious agent may be delayed and for some infections (for example, typhus ) may last for decades.
See also
- Invasion
Literature
- Herzenshteyn G. M. , Sokolov A. m. ,. Infectious diseases // Encyclopedic dictionary of Brockhaus and Efron : in 86 tons (82 tons and 4 add.). - SPb. , 1890-1907.
- Borinskaya S. A. Infections as a selection factor // antropogenez.ru.
Notes
- β Pozdeev Oskar Kimovich. Chapter 1. Renaissance // Medical Microbiology / edited by V.I. Pokrovsky . - 1st ed. - M .: GEOTAR-MED, 2004. - p. 10. - 768 p. - ("XXI Century"). - 1500 copies - ISBN 5-9231-0429-6 .