Anthrax - Causes, Symptoms and Treatment. MF.

Anthrax( malignant carbuncle, Anrhrax, rag disease, sorter sorter disease) is a particularly dangerous acute, saprozootic, bacterial infection with a contact mechanism of transmission and is characterized by serous hemorrhagic inflammation of the skin and other organs against intoxication.

The disease has been known since ancient times under the name "sacred fire", "Persian fire", etc. In prerevolutionary Russia, due to its predominant distribution in Siberia, it was called anthrax. A significant role in this title was played by the Russian scientist S.S.Andreevsky, self-deterring the identity of the anthrax of man and animal, and also pointed to the possibility of transmitting it from animals to humans. Do not worry, Andreevsky was cured.

Anthrax causative agent

Anthrax causative agent

The causative agent is Bacillus antracis, it is a gram-positive( in blue strokes) fixed rod. It is not exacting to nutrient media and forms colonies on them, in the form of filaments leaving from the center, as a result, this growth is often compared with "curls" or "lion's mane".Peculiarities of the structure are pathogenicity factors, i.e. in that it explains the clinical course:

• Upon ingestion, it forms a capsule - it protects the pathogen from phagocytosis( cell destruction of the immune system);
• Outside of the body, under the influence of unfavorable environmental factors, the causative agent forms a spore, which makes it extremely stable.
• Presence of somatic and capsular antigen which is of diagnostic importance in the formulation of Ascoli reaction;
• The presence of a complex toxin that consists of 3 components: the OB - factor of swelling, the action of which is based on accumulation in cAMP cells - activation of this cascade reaction explains the release of Na and Cl from the cell, and after them of water into the intercellular space,there are swelling. PA-protective antigen, the fall of which causes the formation of immunity, the LF-lethal factor causes a lethal outcome, having a cytotoxic effect and summing up the edema factor, by forming a pulmonary edema.

Vegetative forms of anthrax have the same degree of resistance as other bacteria without bacteria, at a temperature above 75 ° C perish in 5-10 minutes, in corpses of animals under the influence of the products of vital activity of putrefactive bacteria and enzymatic factors - death occurs within 7 days. Also, the causative agent quickly perishes under the action of boiling and disinfecting solutions for several minutes.

The situation is different with the spore forming form, which has time to form from the part of the pathogens that have fallen under the conditions of unfavorable factors: in the soil they remain for decades( about 60 years) after the owner's death and, when they again fall into another organism, begin to grow into vegetative formsand again become active. Resistant to boiling - perish for 30-60 minutes. When autoclavable( the effect of steam 100 ° C) - after 40 minutes. Dry heat with a temperature of 140 ° C kills spore forms within 3 hours. Direct UFIs are destroyed for 20 or more days. Disinfection solutions( chloramine, hot formaldehyde, hydrogen peroxide) kill spores within 2 hours.

Susceptibility is universal and is associated with infection routes, the magnitude of the infectious dose and the factors of macroorganism resistance. Geographic prevalence is not limited, but episodic outbreaks are most often recorded in countries with a temperate climate, and mainly in livestock regions in the spring-autumn period. As a result of the repetition of biological cycles( burial of infected animals → entry of pathogens into the soil → formation of spores → eating by other animals of infected grass → infection), the causative agent of anthrax contributes to the creation of long-term active soil foci, ie potentially damaging areas - "damned fields".As such there are no geographical foci, there is a conditional division of the centers: professional-agricultural, professional-industrial and household.

Causes of anthrax

The source of infection is soil( it is a natural reservoir, which is why the disease is called saprozonosis), large and small cattle, horses, camels, wild animals - these animals excrete the pathogen with their biological fluids. Transmission routes are contact( through infected objects of everyday life by the products of animals' vital activity or soil), alimentary( through infected food), air-dust( through air), transmissible( through ectoparasites).

Symptoms of anthrax

The incubation period - the time from the moment of introduction of the pathogen into the macroorganism and up to the first clinical manifestations, can last for anthrax from several hours to 8 days, but more often 2-3 days. The duration of this period will depend on the pathways and the infectious dose of the pathogen. So, for example, when the contact mechanism of transmission occurs, the dermal form develops, and the incubation period is 2-14 days, and in case of aerogenic or alimentary infection a generalized form occurs, in which the incubation period lasts only a few hours, and death occurs on day 2-3.But the contact path does not exclude generalization, the chances of the onset of such a lightning course of the disease as during generalization are simply reduced.

At the site of the pathogen the toxin acts and this indicates the beginning of the next period, because at this place there is a modification of tissues. The period of clinical manifestations is characterized by a sharp onset and depending on the entrance gate there is either skin or generalized form. But in any case, wherever the pathogen has penetrated, there will always be the same mechanism - under the influence of exotoxin damage of the vascular endothelium occurs, as a result of which their permeability is violated, serous hemorrhagic edema, inflammation, hemorrhagic infiltrates and loss of sensitivity in the infection gates:

With a dermal form, a reddish or bluish speck develops at the site of introduction, which resembles a bite of an insect. → A few hours later, this speck is regenerated into a pimple( a virulent bladder- papule) copper-red color → then this pimple turns into a vesicle with serous-hemorrhagic contents, and next - the daughter small bubbles. At the same time, all this skin formation is accompanied by burning and itching, and when combed this bubbles are opened with the formation of an ulcer covered with a dark brown scab( resembles a coal, hence the name of the disease antrax- charcoal) - this indicates the formation of carbuncle( skin inflammation andsubcutaneous fat around the group of hair follicles).Around this formation - hyperemia( redness), edema and loss of pain sensitivity. Not far from the carbuncle, regional lymphadenitis is recorded( an increase in the most closely located lymph nodes - they are dense, mobile, slightly sensitive) and lymphangitis( enlarged lymph vessels located not far from the carbuncle).The presence of lymphadenitis is a sign of drift by macrophages of the pathogen into these lymph nodes. Skin changes occur against the background of general intestinal and fever conditions( 38-40 ° C), as a chill, weakness, headache and low blood pressure. On the 8-10th day of the disease, with proper and timely treatment, there are processes of scarring and epithelization of the ulcer, with a sharp decrease in temperature and an improvement in the overall background state. After another 10-30 days, the scab is rejected and the ulcer heals.

Skin form of anthrax in case of localization on the neck face

Scab in the Siberian anthrax

So the ulcer looks like on the 10th day of the

disease • The generalized form can be either primary, i.e. in case of infection by alimentary or aerogenic pathway, or secondary as a result of occurrencesepticemia due to the spread of the pathogen by lymphogenous and hematogenous pathways. This form is characterized by a violent onset, tremendous chills, acute symptoms of intoxication, headache, vomiting, tachycardia, progressive hypotension( decrease in systemic pressure), deafness of cardiac tones.
When airborne infection occurs the pulmonary form of the generalized course and, in addition, characteristic of the generalized form are the following symptoms: asthma, chest pain when breathing, dyspnea, cough with bloody sputum which almost immediately acquires a jelly-like consistency, weakening of breathing and shorteningpercussion sound speaks about the developed pleurisy( inflammation of the pleural / pulmonary leaves), at a distance different variegated wet rales are heard. With this form, death occurs in 90% of cases and within 2-3 days even during treatment.
When infected with alimentary tract, the intestinal form of the generalized course develops, for which, in addition to general symptoms, the following symptoms are inherent: from the first day of illness, cutting pains in the lower abdomen, bloody vomiting and frequent loose stools with a trace of blood, the intestinal paresis and peritonitis develop rapidly. Anthrax Diagnosis

1. According to the epidemiological data - the study of the place of work( caring for livestock, cutting carcasses, working with skins and skins), conditions and place of residence( countryside), consumption of contaminated products( consumption of meat not passed veterinary and sanitary control, forced slaughter of patientsanimals), etc.

2. According to clinical data - the presence of a black scab with a corolla of hyperemia( "black coal on a red background").This skin formation is cut with a needle and, if the sensitivity is reduced or absent, this gives a chance to confirm the preliminary diagnosis.

3. Laboratory data:
- bacteriological examination by microscopy of smears from the patient's biological material: blood, urine, vomit, bowel movements, sputum
- genetic method( determination of DNA of the pathogen by PCR method, ie polymerase chain reaction)
- serological method: RIF( immunofluorescence reaction) and RNGA( indirect hemagglutination reaction) - these two expert-methods are aimed at determining the antigen. ELISA( enzyme immunoassay) - determines the intensity of immunity.
- immunohistochemical method
- skin and allergic test with anthraxin

4. Additional methods of investigation for suspected generalized form: ultrasound, lumbar puncture, OAB, OAM - they are applicable only to determine the degree of compensation from the organs and the system being examined, to resolve furtherdrawing up a treatment plan.

Treatment of anthrax

Treatment is a complex, consisting of etiotropic, pathogenetic and symptomatic therapies. It is also necessary to comply with bed rest for the period of the disease and adhere to the therapeutic diet - table number 13, and in severe cases go to enteral-parenteral nutrition( ie, partially normal feeding, and in part - intravenous drip).

1. Etiotropic therapy is aimed at the destruction of the pathogen, with the use of such drugs as ampicillin, doxycycline, rifampicin, pefloxacin, ciprofloxacin, gentamicin, amikacin - they are combined with each other and used in appropriate age-related dosages for 7 days, and for severe currents -for 14 days.
2. Pathogenetic therapy consists in the management of anti-STI immunoglobulin.
3. Local treatment consists only in the treatment of affected skin with solutions of antiseptics. Bandages do not impose, surgical treatment is not applied, because it can provoke generalization of the infection.
4. When developing life threatening complications( ITT - infectious toxicity shock), prednisolone( the strongest SCS) is used, detoxification therapy is used to control hemodynamic disorders - polyionic solutions are applied with the addition of polyglucin, rheopolyglucin or hemodesum.

An extract of convalescent patients with dermal form is carried out after the removal of the scab and formation of a scar. In generalized forms, complete clinical recovery and a double negative result of bacteriological studies with a 5-day interval are prescribed. The management of such patients in a home hospital is unacceptable.

Anthrax complications

ITH, sepsis, meningitis, ODN( acute respiratory failure)

Anthrax prevention

Veterinary: detection and timely diagnosis, followed by treatment or slaughter of sick animals, epizootic examination of the outbreak, disinfection of corpses, destruction of meat / skins / wool of deadanimals, current and final disinfection in the outbreak, recovery of cattle grazing / pasture / unfavorable territories, as well as routine immunization with live anthraxaktsinoy farm animals in disadvantaged areas. Medical and sanitary measures:

• control over observance of general sanitary norms in the procurement, storage, transportation and processing of raw materials of animal origin;

• Vaccine prophylaxis with live spore dry capsule vaccine - twice planned( in potentially dangerous areas) or unplanned( according to epidemiological indications followed by revaccination annually);

• timely diagnosis, hospitalization and treatment of patients;

• epidemiological examination of the outbreak, followed by current and final disinfection;

• prohibition of autopsies due to high risk of contagion;

• people who come into contact with sick people or animals are injected with anti-STI immunoglobulin and etiotropic drugs for 5 days, and the contactee is observed for 14 days.

Consultation of an anthrax doctor:

Question: Is a sick person dangerous?
Answer: Sick people do not pose a danger to others, but in contact with them for prevention purposes, they still passive immunization.

Question: Is immunity formed after the transferred disease?
Answer: it is formed, but not prolonged and not resistant, there are cases of repeated diseases.

Question: What does vaccine prevention give?
Answer: The vaccine is considered highly effective and dramatically reduces the risk of morbidity.

Doctor therapist Shabanova IE