Anthrax is the sharp, especially dangerous infectious disease arising at the person and animals at Bacillus anthracis infection, proceeding with formation on skin of a specific anthrax or in a septic form. A source of an infection are wild animals and the cattle, infection occurs in the contact way. The incubatory period of anthrax averages 3-5 days. Diagnostics is performed in 3 stages: microscopy of a phlegm or separated skin elements, , biological tests on laboratory animals. Treatment of anthrax is performed by penicillin. At a skin form it is combined with local treatment of ulcers and anthrax.
Anthrax is the sharp, especially dangerous infectious disease arising at the person and animals at Bacillus anthracis infection, proceeding with formation on skin of a specific anthrax or in a septic form.
Characteristic of the activator
Bacillus anthracis represents the large, encapsulated, grampolozhitelny, facultative and anaerobic, sporoobrazuyushchy bacterium of a rhabdoid form with the chopped-off ends. Forms disputes at contact with oxygen, in such look the long time can remain in the environment (several years in water, decades in the soil, sometimes sprouting also forming new disputes). Keeps viability after five minutes of boiling, perishes only after 12-15 minutes of influence of fluid steam, within 5-10 minutes at a temperature of 110 °C. Dry heat with the temperature of 140 °C needs for destruction a dispute of bacteria 3 hours, to disinfectants (1% solution of formalin, 10% of a caustic natr) – 2 hours.
Vegetative forms in the external environment are unstable, perish at boiling and disinfection. The Sibireyazvenny stick allocates three-component (anti-gene, edematous and lethal factors) which is quite unstable, collapses when heating to 60 °C. A source and the tank of anthrax in the habitat are herbivores, in settlements – a livestock (large and small). At animals anthrax proceeds in a generalized form, transmissibility takes place throughout all disease (animals allocate the activator with excrements) and within 7 days after death (without opening and a razdelyvaniye of ink). The skin, wool and products of their processing can keep transmissibility for many years.
Infection of animals occurs at the use of food or water containing anthrax disputes, or at stings of the insects transferring the activator from sick animals, the infected corpses polluted by disputes of objects. Special danger is constituted by the disputes remaining in the soil forming the epidemic center which can be mentioned when carrying out construction, hydromeliorative, geophysical and other works therefore disputes of anthrax come to a surface and can infect animals and the person.
The sick person does not constitute significant epidemiological danger to other people, but can be a source to an infection for animals. The mechanism of transfer of anthrax, as a rule, contact (penetration of the activator happens through the damaged integuments and mucous membranes). Most often people catch at contact with sick animals and processing of hulks, production of objects from animal raw materials, culinary processing of the infected meat. Incidence of anthrax is subdivided on professional and household. Cases of realization of a food way of transfer, and also inhalations of bacteria are extremely rare.
The natural susceptibility of the person to anthrax low, development of a disease occurs at 20% of the persons which had contact with the activator, but at realization of an air and dust way of infection incidence almost absolute. Men of active age, generally in rural areas catch anthrax more often.
Classification of anthrax
Anthrax proceeds in two clinical forms: skin and generalized.
- The skin form which is found in most cases (95% and more) is subdivided into karbunkulezny, bullous and edematozny versions, depending on the nature of skin manifestations.
- The generalized form also happens three types: pulmonary, intestinal and septic.
The incubatory period of anthrax usually takes 3-5 days, but can drag on also about one one or two weeks, and also proceed within several hours. The most common clinical form of anthrax: karbunkulezny. At the same time on skin in the place of introduction of the activator the anthrax is formed, passing consistently stages of a spot, a papule, a vesicle and an ulcer. At first the red painless spot which is quickly transformed in copper-colored (sometimes crimson), raised over the surface of skin, a papule is formed. At this stage of patients the itch and some burning of an affected area usually disturbs.
Several hours later the papule progresses in the vesicle filled with serous liquid about 2-4 mm in the diameter. Vesicle contents soon get dark, sometimes crimson-violet, a shade as a result of a gemorragiya. Being opened (independently or when combing), the vesicle forms an ulcer with a dark brown bottom, raised edges and separated serous and hemorrhagic character. At a typical current primary ulcer is surrounded with new vesicles which when opening merge and increase ulcer defect.
Several days later (sometimes up to two weeks) in the center of an ulcer the black necrotic scab is formed, gradually replacing all its bottom. By sight the anthrax reminds the burned crust, painless, is surrounded with the purple-red inflammatory roller towering over not affected skin. To fabric around an anthrax it is expressed are edematous, quite often hypostasis occupies the considerable site (in particular in case of localization in places with friable hypodermic cellulose, on an example, on a face). At an anthrax arrangement on a face the probability of distribution of puffiness on the top airways and development of life-endangering asphyxia is high.
The disease from the very beginning is followed by considerable intoxication (the headache, weakness, an adinamiya, an ache in muscles, a waist, is possible belly-ache), fever. In five-six days body temperature sharply decreases, there is a regress of the general and local clinical manifestations. The scab is torn away 2-3 weeks later, the ulcer gradually heals, leaving a rough hem.
As a rule, the anthrax is formed in a single copy, in rare instances their quantity can reach 10 and more that considerably makes heavier the course of a disease. The greatest danger is constituted by the anthrax on the head, a neck, mucous membranes of a mouth and a nose considerably worsening a current and threatening to be complicated by sepsis.
The Edematozny form at the first stage is limited to puffiness of fabrics, the anthrax is formed later and differs in quite large sizes. The bullous version is characterized by formation in the field of entrance gate of an infection of the bubbles filled with hemorrhagic contents which are transformed after opening to the extensive ulcers progressing in an anthrax.
At generalized forms of anthrax primary damage of respiratory organs (a pulmonary form) is characteristic. Clinical manifestations remind those at flu: symptoms of intoxication are followed by cough, cold, dacryagogue, breath increase, tachycardia, short wind is noted. This phase of a disease can proceed from several hours to two days then there is a considerable increase of symptoms of intoxication, fever reaches critical figures (39-40 degrees), the fever is expressed. Sometimes during this period pains and constraint in a thorax are noted, at cough the plentiful phlegm with bloody impurity is allocated, when folding reminding cherry jelly. In the subsequent there is an increase of an oliguriya, signs of cardiovascular insufficiency, hypostasis of lungs. Duration of the last phase of a disease does not exceed 12 hours, patients are in consciousness.
Most hard the intestinal kind of a generalized form of anthrax having extremely a failure proceeds. The first phase as well as in other cases it is characterized by fever and the expressed intoxication, the followed burning and morbidity in a throat, and proceeds up to one and a half days, then the expressed cutting belly-ache, nausea, vomiting with blood, diarrhea joins this symptomatology. In kalovy masses blood also visually is defined. In the third phase the accruing warm decompensation takes place, the person gets a crimson or cyanotic-pink shade, injections a skler are noted, on skin there can be petekhialny or hemorrhagic rashes. Patients are disturbing, feel fear.
The septic kind of a generalized form proceeds in the form of primary or secondary (been a complication of other form of anthrax) sepsis. At the same time very bystry increase of symptomatology of intoxication, numerous gemorragiya on skin is noted and mucous, brain covers often are surprised. This form, often, progresses with development of infectious and toxic shock.
Anthrax can be complicated by meningitis, meningoentsefalita, hypostasis and swelling of a brain, hypostasis of lungs, asphyxia, peritonitis, gastrointestinal bleedings and paresis of intestines. Generalized forms easily develop into sepsis and infectious and toxic shock.
Diagnosis of anthrax
Specific diagnosis of anthrax includes three stages: a microscopic research of biological materials (a phlegm, separated skin elements, a pleural exudate, kcal), allocation of culture by a bakposev on nutrient mediums and biological tests on laboratory animals. As serological methods of diagnostics apply reaction of a termopretsipitation across Askoli, the luminescent serological analysis, some other techniques. The patient make skin and allergic test with antraksiny.
The X-ray analysis of lungs at a pulmonary generalized form shows a picture of pneumonia or pleurisy. In such cases additional consultation of the pulmonologist is necessary for the patient with anthrax. If necessary carry out a pleural puncture. At the beginning of a disease differentiation of skin displays of anthrax requires consultation of the dermatologist. All researches with a sibireyazvenny stick are made in the specialized equipped laboratories in connection with special danger of this disease.
Treatment of anthrax
Etiotropny treatment of anthrax is performed penicillin, appointing it intramuscularly to 7-8 days or more, before removal of symptoms of intoxication. Inside it is possible to appoint doxycycline or . At a heavy current apply intravenous injections of ciprofloxacin. Along with antibiotic treatment appoint introduction of protivosibireyazvenny immunoglobulin (it is entered warmed up in half an hour after Prednisolonum injection).
Dezintoksikatsionny therapy – infusional introduction of dezintoksikatsionny solutions with Prednisolonum and speeding up of a diuresis is shown to patients with anthrax. Heavy complications treat according to the developed techniques of intensive therapy. Aseptic bandages are applied ulcers and an anthrax. Expeditious removal of an anthrax is categorically contraindicated in view of possible generalization of an infection.
Forecast and prevention of anthrax
The favorable forecast have the skin forms of anthrax, generalized forms quite often come to an end with a lethal outcome. Modern methods of treatment promote considerable decrease in failures of this disease therefore the timely request for medical care is extremely important.
Sanitary and hygienic actions for prevention of incidence of anthrax I include veterinary and medical and sanitary measures which problem is identification, control and sanitation of the epidemiological centers, tracking of a condition of pastures, water sources, livestock farms, planned inoculations of animals, hygienic rationing when processing animal raw materials, its storage and transportation, burial of the fallen cattle.
Individual prevention consists in observance of sanitary and hygienic rules during the work with animals, specific vaccinal prevention for persons with high professional risks of infection. The revealed centers are subject to disinfection. The emergency prevention is performed no later than 5 days after contact with suspicious objects, represents a course of preventive antibiotic treatment.