Anthrax is an infectious disease. It is characterized by a high probability of death. Causative agent of anthrax - Bacillus anthracis. Farmers are at risk since infection occurs by contact with animals. Disease anthrax, a photo of the results of which can scare anyone, is dangerous for several reasons: it is quite common in the animal world, the spores of the causative agent of the disease are stored for a long time in the soil of a cattle burial ground, the disease is difficult and gives complications.
Description
The causative agent of anthrax is a fixed large bacterium. Being in the human or animal body, it forms a capsule, in the external environment - a spore.
Spores of the causative agent of the disease can last about 10 years in the soil, and in cattle burial grounds - up to five times longer. They are not afraid of frost and heat, they are able to survive in solutions of bleach and chloramine, and they withstand boiling for 7 minutes.
Everyone knows cases where the causative agent of anthrax was used by terrorists and spread in envelopes.
The vegetative form of bacteria quickly dies after disinfection and boiling. The anthrax bacterium is able to go into a sleeping form and become active under favorable environmental conditions.
History
Since ancient times, anthrax has been affecting humanity. Even Homer and Hippocrates referred to it as "sacred coal." In the Middle Ages, this disease claimed the lives of many people and animals in different countries. The disease was first described in the XVII century. Russian scientist S.S. Andreevsky proved that anthrax in animals and humans is the same disease that occurs through self-infection. He also appropriated this ailment with a modern name.
At the end of the 19th century, Louis Pasteur was able to create the first vaccine. He introduced animals to an attenuated anthrax bacterial strain, which led to the development of immunity. Pasteur was able to prove the need for vaccination to prevent the disease.
WHO reports about 20 thousand anthrax cases annually. Research is underway to improve the vaccine and increase its duration. In 2010, US scientists were able to introduce the anthrax gene into the tobacco genome. As a result of these actions, an antigen was produced in plants, which was used to create a new vaccine that practically did not cause side effects.
Epidemiological process
Anthrax is transmitted to humans through livestock. Birds are immune to this disease, but they can carry spores on feathers, claws, and beaks.
An anthrax bacillus in a sick animal is found in the stool, blood, fluid secreted from the nose and mouth. The pathogen enters the soil and water with urine and feces.
The soil at the site of the death of sick cattle becomes infected, and wild animals, pulling out a corpse, can spread the disease for many kilometers.
Infection from one person to another does not occur, therefore, the level of disease in people directly depends on the epidemic in animals.
Infection can occur through soil, in contact with infected livestock products, in caring for sick animals, in opening their bodies, through skin injuries, food and inhaled air.
In African countries, where anthrax in animals is especially common, its transmission to humans can occur through the bite of a blood-sucking insect.
Who is at risk
There are several groups of people who are particularly at risk of infection:
- veterinarians in contact with animals;
- manufacturers, sellers, as well as buyers of products from natural fur and wool brought from regions where the disease is common;
- hunters;
- military personnel and other categories of citizens located in areas of the epidemic;
- people working in laboratories, in direct contact with the causative agent of anthrax.
Prevalence
In no country has anthrax been completely eradicated. Most often it is found in Africa and South America, as well as in countries of the Asian region. In Europe, the epidemic periodically occurs in its southern part, on the Black Sea and Mediterranean coasts. The leaders in the number of anthrax patients are Turkey, Iran and Iraq.
In Russia, this disease is most often found in the North Caucasus region. The main reason for its occurrence in our country is the slaughter of an infected animal without notifying the veterinary service about it and without taking the necessary disinfection measures.
Features of the spread of the disease:
- in developing countries, infection occurs after contact with an animal, caring for it, slaughter;
- in developed countries, the infection is transmitted primarily through industrial raw materials of animal origin.
Classification of ailment
The following forms of anthrax are distinguished:
- skin;
- intestinal;
- pulmonary.
The skin form is most common (approximately 95% of the total number of cases). It can be carbuncleous (the most common), bullous, endematous and erysipeloid.
Pulmonary and intestinal forms are often combined under one name - a generalized or septic ulcer. The intestinal form of the disease is least likely to occur (in less than 1% of cases).
Symptoms and course of the disease
The latent period of the disease can last from several hours to a week. A different amount of time may elapse from the moment a pathogen reaches a person until the first symptoms appear (depending on the route of infection). With the air and food method of infection, the development of the disease occurs with lightning speed, and death can occur in a few days.
Regardless of the form of the anthrax, the mechanism of its development is the same: the toxin damages the vessels, violates their permeability, resulting in edema, inflammation and loss of sensation.
The most common carbuncular anthrax (photo of the causative agent of the disease is presented below).
The onset of the disease is characterized by the appearance of a red spot on the skin at the entry site of the infection, which subsequently turns into a papule, and then into a dark vesicle. Bursting, the vesicle transforms into an ulcer with raised edges, around which new vesicles may appear. After a while, a black scab forms in the ulcer, similar to charred skin. The sensitivity of the integument around the scab disappears. Its external similarity to coal led to the appearance of the old Russian name for anthrax - carbohydrate.
Edema appears around the affected skin. It is dangerous if a carbuncle occurs on the face and can lead to swelling of the respiratory tract and death.
The course of the disease is accompanied by fever, aches, headache. After a few weeks, the ulcer heals and a scar appears.
Endemic anthrax is characterized by edema, the carbuncle appears at a later stage of the disease and is large in size.
With a bullous variety of the disease, blisters appear at the site of infection, which, after opening, turn into ulcers.
The pulmonary form of the disease is often called a disease of wool sorters. The anthrax bacterium with air enters the lungs, and from there into the lymph nodes, which become inflamed. Initially, the patient has a high fever, chest pain and weakness. After several days, shortness of breath and a decrease in the level of oxygen in the blood appear. Once in the lungs, the causative agent of anthrax quickly spreads throughout the human body. Often there is a cough with blood, an x-ray can show the presence of pneumonia, the patient’s body temperature often rises to 41 degrees. There is pulmonary edema and cardiovascular failure, as a result, hemorrhages in the brain are possible.
After the pathogen enters the human body with food and drink, an intestinal form of anthrax develops. The first phase of the disease lasts about 2 days and is accompanied by sore throat, fever, and fever. Subsequently, vomiting with blood, severe abdominal pain, diarrhea are added to these symptoms. Cardiovascular insufficiency appears, the face becomes purple or cyanotic, papules form on the skin. With intestinal anthrax, the probability of death of the patient is high.
With a septic form, the disease proceeds rapidly, intoxication, internal hemorrhages occur. The consequence of such an ailment can be an infectious toxic shock.
Diagnostics
Laboratory diagnosis of anthrax includes the following:
- serological studies ;
- bacteriological studies;
- skin and allergic tests.
With a skin form of the disease, the doctor will make a diagnosis based on changes in the skin of the patient. If there is a suspicion of a pulmonary form, they do fluorography and tomography, take nasal swabs and sputum samples.
The causative agents of infectious diseases can also be determined by taking blood for bacterial cultures, examining samples of abdominal fluid, lumbar puncture, and analysis of skin scrapings.
Possible complications
Anthrax can lead to cerebral, pulmonary edema, gastrointestinal bleeding, meningitis. With generalized forms of the disease, an infectious-toxic shock often develops.
Treatment
Patients should be in the infectious department, with a severe course of the disease - in the intensive care unit. In no case should you open the carbuncle, so dressings should be carried out with extreme caution. With a generalized form of the disease, the patient should be constantly monitored in order to prevent toxic shock in time.
The causative agent of anthrax is destroyed with antibiotics. Apply them for 7-14 days, depending on the severity of the disease. Simultaneously with antibiotic therapy, the patient is given an anti-anthrax immunoglobulin. Affected areas of the skin are treated with antiseptics. At home, treatment for anthrax is not possible.
Forecast
The discharge of patients with a skin form of the disease occurs after scarring of the affected skin, with a generalized form, a complete recovery and a double negative result of bacteriological studies are necessary.
Most often, pulmonary and intestinal forms of the disease lead to death. With skin anthrax, a full recovery occurs if timely medical care is provided.
People in contact with the causative agent of anthrax take antibiotics for 60 days.
Prevention: General Information
Veterinary and health prophylaxis of anthrax is performed.
Veterinary services are required to identify sick animals with subsequent treatment or slaughter. Fallen cattle are disinfected and destroyed, and disinfection is carried out in the outbreak.
Health services should:
- monitor compliance with general sanitary standards;
- timely diagnose and treat the disease;
- examine and disinfect the focus of the disease;
- to vaccinate.
There is an anthrax vaccine that protects animals from this disease. In farms, vaccination is carried out without exception, but not all people who have livestock in their possession understand the need for this procedure.
The main measures for the prevention of anthrax
- annual vaccination of cattle against anthrax;
- clarification by veterinary services of the rules for slaughtering animals that died from anthrax;
- reliable protection of cattle cemeteries and epidemic sites;
- refusal to buy meat that does not have the stigma of veterinary service, as well as leather and fur from the hands;
- burning a dead animal infected with anthrax, burning the land where sick cattle lay, disinfecting rooms with bleach;
- imposing quarantine on the place where the anthrax cattle disease is established;
- vaccination of people whose professional activities are associated with the risk of contracting an illness such as anthrax (the vaccine is effective for a year);
- sanitary supervision at enterprises processing animal raw materials;
- infectious agents can be found in food; therefore, the rules for processing and preparing meat and dairy products should be followed.