Anthrax is an acute infectious disease caused by the bacterium Bacillus anthracis (BA). BA is especially dangerous because it typically occurs in the environment (such as soil) as microscopic endospores.
These spores, as they are commonly called, are dormant structures that can survive for many years, even when exposed to very hot or cold temperatures, dry conditions, chemicals, radiation or other factors. Contact with anthrax bacteria or viable spores can result in severe infection in both humans and animals.
Although anthrax is a very serious illness, it is not contagious like the cold or flu. People and animals can become infected in a variety of ways: through the skin, inhalation or ingestion, contact with anthrax-infected animals, contaminated animal products, or other sources of anthrax spores.
Biological agents, such as anthrax, have a direct impact on worker safety, and biological assessments are used to determine the extent of exposure.
Routes of infection with anthrax
Anthrax is very rare. However, cases have been observed in travelers from countries with higher prevalence rates and in workers who handle livestock products from areas where anthrax is endemic (i.e. regularly detected).
The last episode of anthrax infection in the Republic of Belarus was detected in August 2021 - in a horse from the Stolin region; in 1997, 6 people became infected.
There are three most common forms of anthrax, which result from three ways through which someone can be exposed to Bacillus anthracis (BA) or its spores:
- Skin infection from contact exposure;
- Infection associated with inhalation exposure (eg, inhalation of bacteria or spores);
- A gastrointestinal infection associated with ingestion of contaminated materials, such as raw or undercooked meat from an anthrax-infected animal.
Two other types of anthrax, oropharyngeal (infects the mouth and throat) anthrax and meningeal (infects the membranes covering the brain and spinal cord) anthrax, are secondary complications of the three main types of anthrax listed above. Less common than the gastrointestinal form, oropharyngeal anthrax is also associated with the consumption of contaminated meat, but is generally milder than the classic gastrointestinal disease, with a better prognosis.
Meningeal anthrax is a rare complication of anthrax (usually cutaneous anthrax) in which the bacteria spread to the central nervous system. Despite intensive antibiotic therapy, meningeal ulcers are almost always fatal.
Injection anthrax has been identified among heroin drug users in Northern Europe. Injection anthrax is not typically associated with the work tasks that lead to this type of occupational exposure.
Classification
Anthrax is divided into two types - cutaneous and general (generalized). In turn, each of these varieties has several more forms.
There are three types of skin forms of the disease:
- Carbunculous - manifestations on the skin change from red spots to nodules, and then to dark ulcers. The patient is worried about weakness, chills, fever .
- Edematous - in the first days of the disease, large swelling appears on the skin. Later, a scab is observed, around which the skin turns red.
- Bullous - the disease begins with the appearance of blisters on the skin. Later they burst, resulting in extensive ulcers. Later, a characteristic black crust appears on their bottom.
The general (generalized) form is divided into three types:
- Pulmonary – the respiratory organs are affected. With this form of the disease, the prognosis is most often unfavorable.
- Intestinal - very difficult, there are signs of gastrointestinal damage and general intoxication. High risk of death, even if the patient is provided with adequate treatment.
- Septic – sometimes develops immediately, sometimes as complications of other forms. There is general intoxication and bleeding in the internal organs. Inflammation of the membranes of the brain and failure of internal organs often occur.
Anthrax and professional activity
Contact with infected animals or people can cause anthrax. The following is known about the routes of infection:
- Most anthrax infections are cutaneous and result from Bacillus anthracis spores entering cuts or abrasions on the skin, such as when handling contaminated fur, animal skins, skin, or hair products from infected animals. In some cases, such as when working with active bacteria in laboratories, contact with active bacteria can cause infection.
- Inhalation anthrax can occur when a person inhales airborne spores produced by handling animal skins, fur, or hair contaminated with the spores . In laboratories, processes in which BA or its spores are sprayed, or activities that are not carried out with adequate controls (for example, in biosafety cabinets) can lead to exposure.
- Gastrointestinal anthrax can occur after eating contaminated meat and other foods.
Anthrax (synonyms: malignant carbuncle; anthrax - English) is a particularly dangerous infectious disease of agricultural and wild animals of all types, as well as humans.
The causative agent of anthrax, Bacillus anthracis, exists in two forms: bacillary (vegetative) and spore. The spore form is resistant to external influences and can maintain the viability and virulence of the pathogen in the soil for several decades.
A permanently unfavorable locality is a populated area, a livestock farm, a pasture, a tract on the territory of which anthrax disease has been recorded among animals, an outbreak, regardless of the statute of limitations.
Soil foci are considered to be cattle burial grounds, biothermal pits and other places where the corpses of animals that died from anthrax are buried.
A sanitary protection zone is established around soil foci of anthrax, the size of which is determined taking into account the characteristics of the area and the type of proposed work.
All species of mammals are susceptible to anthrax. Sheep, cattle, horses, goats, buffaloes, camels and reindeer are most often affected; donkeys and mules can become infected. Pigs are less sensitive. Among wild animals, all herbivores are susceptible. There are known cases of the disease in dogs, wolves, foxes, arctic foxes, and among birds - ducks and ostriches.
VARIETIES OF ANTHRAX
There are three forms of this disease: pulmonary, intestinal and cutaneous. The first two are extremely rare, but they are the most terrible: usually the disease with these forms of anthrax ends in death.
YOU CAN GET INFECTED WITH ANTHRAX
- upon contact - direct contact with sick livestock, when the microbe gets into microtraumas of the outer skin (scratches, abrasions, small cuts) during the care of animals, when opening their corpses, skinning and cutting up carcasses,
- through contaminated objects - through wounds and cracks on the hands,
- when eating contaminated meat and water that has not been thermally processed sufficiently,
- by airborne droplets when inhaling bacilli.
A sick person does not pose an epidemiological danger.
The Brest region is classified as an anthrax-prone area. There are 67 soil burials of animals that died from anthrax in different years.
The presence of animals and people on the territory of such a soil burial ground that are not vaccinated against anthrax can lead to infection.
Among animals, the alimentary route of infection is of important epizootological importance - through food and water contaminated with anthrax spores; aerosol, vector-borne infection through milk and dairy products are of less importance. The pathogen can be transmitted by horseflies and burner flies, in whose mouthparts the pathogen can survive for up to 5 days.
The greatest epizootic and epidemiological danger is posed by grazing animals in areas near undeveloped anthrax cattle burial grounds, as well as in pastures where there have been deaths of livestock and unauthorized burials of animal corpses. Mostly unvaccinated animals become ill with anthrax.
SYMPTOMS OF THE DISEASE
With the cutaneous form of anthrax, at the site where the infection has occurred, the skin first appears itchy, a purulent spot appears, which then begins to bubble, after 2-6 days it turns into an ulcer, covered with a black scab. At the same time, the patient’s temperature rises, his head hurts, and his body aches. A complication in the absence of specific treatment is septicemia.
With pulmonary anthrax, the first symptoms are similar to the flu: the temperature rises, the person is very chilly, and sputum begins to be produced abundantly from the chest. After 3-5 days, acute pulmonary failure develops, leading to shock and death.
With the intestinal form of anthrax, severe abdominal pain, vomiting, and loose stools with blood begin.
The incubation period of the disease can be from several hours to 8 days, more often it is 2-3 days.
HEALTH CARE
At the first signs of illness, you should consult a doctor who will determine the course of treatment.
Antibiotics have been successfully used to treat anthrax.
HOW TO PREVENT ANTHRAX INFECTION?
- It is mandatory to invite a veterinary specialist to conduct a pre-mortem examination of the animal.
- Immediately report all suspected cases of illness and death in livestock to veterinary institutions.
- Isolate identified sick animals and burn their corpses. Burying animals that have died from anthrax is strictly prohibited.
- In case of forced slaughter, it is prohibited to sell meat and other products for human consumption and animal feeding without laboratory testing. This measure is provided for by the veterinary and sanitary rules for the examination of meat and meat products in all cases of forced slaughter and in anthrax-free areas. Citizens, individual entrepreneurs, legal entities processing and selling meat, meat products, hides and other livestock raw materials are required to comply with requirements aimed at ensuring their safety for the population.
- The use of personal protective equipment (mask, respirator, gloves) when cleaning livestock premises, working with skins, wool, down, etc. in stationary areas affected by anthrax.
- Equipping soil foci of anthrax burials with a fence impenetrable to animals and people.
- Prohibition of any work on the area of the soil outbreak and in the sanitary protection zone. Mandatory approval of agro-reclamation, construction and other work related to the excavation and movement of soil from anthrax burials is carried out with the bodies authorized to carry out state sanitary and epidemiological supervision.
- Prohibition of the use of territories located in the sanitary protection zone of the anthrax cattle burial ground for any economic activity (organization of pastures, arable land, vegetable gardens, watering places, work related to the excavation and movement of soil, construction of residential, public, industrial or agricultural buildings and structures ).
Routine immunization of farm animals in hospital-prone areas is carried out by the veterinary service.
Department of Epidemiology of the General Public Institution of the State Institution "Brest Regional Center for Geology and Health"
Health and Safety Measures to Protect Against Anthrax
Historically, Bacillus anthracis (BA), which causes anthrax, was an occupational hazard most commonly encountered in animal handling and related occupations. However, the potential for accidental or intentional release of BA and ongoing laboratory research to improve preparedness to respond to and counteract such releases mean that a wider range of workers may be at risk of occupational exposure.
The level of risk in any particular workplace depends on factors such as:
- Possibility of contracting BA in the workplace;
- Proximity of the workplace or workplace to areas known to be contaminated with anthrax spores;
- The likelihood of receiving items from a contaminated facility at the workplace;
- Type of workplace.
The first step for any employer in recognizing the potential hazards of BA exposure that its employees may face is to conduct a hazard and risk analysis of the job. Job hazard analysis is a process that focuses on job tasks to identify inherent hazards and implement control measures to protect workers.
Diet
Diet 13 table
- Efficacy: therapeutic effect after 4 days
- Time frame: no more than 2 weeks
- Cost of products: 1500-1600 rubles per week
Patients are recommended to follow Diet 13 table . Recommended dishes include lean meat and fish, slimy soups and low-fat broths, dairy products, eggs, cereal porridges, vegetables, fruits, tea, rose hip decoction, etc.
A number of products are prohibited from consumption. This list includes:
- Spicy dishes.
- Fat meat.
- Fresh bread and pastries.
- Sausages and canned food.
- Fat cheeses and sour cream.
- Products that increase gas formation - legumes, cabbage.
- Coffee, alcohol.
More detailed information is contained in the “diet” presentation.
Consequences and complications
Anthrax can lead to serious complications, including:
- Brain swelling.
- Inflammation of the membranes of the brain.
- Bleeding in internal organs.
- Intestinal paresis.
- Inflammatory process in the intestines and abdominal cavity.
- Pneumonia.
- Pulmonary edema.
- A drop in blood pressure to a state incompatible with life.
Diagnostics
The result of simple microscopy helps to establish a preliminary diagnosis. The method of inoculating biological material on nutrient media is a classic method for determining the causative agent of anthrax. Results are obtained within 36 – 48 hours. To carry it out, discharge from the carbuncle, blood from a vein, sputum, urine, feces, and cerebrospinal fluid are used. The biological method is based on the isolation and identification of pathogens from the tissues of animals infected with anthrax bacteria. A skin allergy test is carried out to determine antibodies to the pathogen in the patient’s body.
Rice. 16. The photo shows the causative agents of anthrax. On the left is a view under a microscope. On the right is the culture of the pathogen.
Disease prognosis
Cutaneous form of the disease . Mortality rate is up to 2% if treatment is not started in a timely manner. Up to 20% - in the absence of treatment.
Pulmonary form of the disease . Mortality is high. Even with timely and adequate treatment it is 90 – 95%.
Intestinal form of the disease . The mortality rate reaches 50%. Anthrax meningitis. The mortality rate reaches 90%.
Septic form . The prognosis is unfavorable even with timely and adequate treatment.
Prevention
Prevention of the disease is carried out in close contact with the veterinary service.
Epidemiological surveillance
Anthrax surveillance activities include:
- identification of a population at high risk of disease,
- establishing the time of the incident;
- identification and strict accounting of disadvantaged settlements, livestock farms and pastures;
- identification and strict registration of cattle burial grounds and other burial places of sick animals;
- examination of soil samples during the construction of buildings for children;
- conducting active monitoring and analysis of morbidity rates in animals and people;
- carrying out work on the exchange of information between veterinary and medical services.
Veterinary and sanitary supervision
Activities for veterinary and sanitary surveillance of anthrax include:
- identification and elimination of epizootic foci;
- imposition of veterinary quarantine;
- vaccination of livestock;
- carrying out bacteriological research of cattle burial grounds, pastures and reservoirs.
Rice. 18. Veterinary service specialists, at the slightest suspicion of anthrax, go to the scene of the incident and take samples of biological material, which are sent to the veterinary laboratory.
Rice. 19. Carcasses and skins of sick animals are burned and the area is disinfected.
Rice. 20. Burning the corpses of sick animals.
Rice. 21. Declaration of quarantine in the outbreak of the disease.
Epidemiology of the disease
Anthrax has been registered in the North Caucasus, Southern and Siberian federal regions of the Russian Federation over the past five years. In total, 40 people fell ill. This number exceeded the identified patients over the previous five years by 43%.
Humans become infected from domestic herbivores - sheep, large and small cattle, horses, camels, donkeys, deer and pigs. Pathogenic bacteria are released into the external environment through urine, saliva, feces, milk and discharge from wounds. In animals, the disease occurs in the form of a septic form. After their death, all organs remain contagious, even skin, wool and bones. In a spore-like state, anthrax pathogens persist for decades in manure and soil.
Rice. 3. The photo shows anthrax in a cow.
Rice. 4. The photo shows anthrax. Carbuncle on the face.
Treatment and prevention
Anthrax is treated with antibiotics. It is aimed at combating the pathogen and increasing the patient’s body’s defenses. If the course of the disease is favorable, after 5-7 days the temperature drops sharply, and a scar forms in place of the scab. If the outcome is unfavorable, secondary sepsis and death may develop.
Anthrax is a very dangerous disease, so the veterinary service takes preventive measures to prevent an epidemic. In areas where it is detected, quarantine is introduced, and the population is evacuated to safe places.
Animals with anthrax are isolated and their corpses are burned. Disinfection of infected objects is also carried out.
Vaccination of people and animals is of great importance for the prevention of anthrax.
