The Anthrax is an acute infection caused by the bacterium “Bacillus anthracis” which affects, primarily, to animals, which can then transmit it to the man (it is therefore a zoonosis). Also called malignant carbuncle or malignant pustule.
This microorganism has a worldwide distribution. It mainly affects domestic herbivorous animals (mainly cattle and sheep) and, therefore, people in contact with them (shepherds, shearers, butchers, veterinarians, furriers, etc.).
There are between 200 and 300 cases of anthrax a year in humans in Spain. The most frequent form of affectation is cutaneous (95% of cases).
Why is it produced?
The cause of this disease is a gram-positive, aerobic or facultative anaerobic bacillus, encapsulated and large, called Bacillus anthracis, which forms spores and a type of toxin.
Animals become infected by ingesting pastures contaminated with the spores of the bacillus, subsequently causing infection to humans. This is mainly cutaneous (by contact with the animal or by insect bites), although there are also cases of inhalation (wool carder disease) or ingestion (by consumption of undercooked infected animal meat).
The spores enter the body and, after a short incubation period (2-5 days), give rise to the growth of bacteria that produce the toxin, which causes the disease. In the case of cutaneous anthrax , tissue necrosis , hemorrhage, and an inflammatory reaction occur , with significant edema.
In inhalational anthrax, the spores reach the lungs, from where they pass into the mediastinum, causing hemorrhagic mediastinitis. Digestive anthrax is mainly characterized by intestinal involvement.
In these last two cases, the disease is much more serious than in the cutaneous one, having a high mortality. It can cause bacteremia (bacteria in the blood), which can be fulminant, and is more frequent in respiratory and digestive cases.
As we have already said, the most common type of anthrax affects the skin, usually in bare areas, such as the head, face, neck or extremities.
This is characterized by the appearance (after the incubation period), at the place of inoculation (entry) of the spores, of a reddish macula (spot) that causes itching (itching); it becomes a painless papule and later a vesicle or ring of vesicles; These rupture and a clear exudate (fluid) emerges.
Later, the lesion turns into a pustule. After a week, the lesion ulcerates and turns into a painless, necrotic black eschar, surrounded by a very characteristic intense hard edema.
Painful regional lymphadenitis is common. In general, there is no fever or systemic symptoms. There may be bacterial superinfections. Spontaneous healing occurs in 1 to 3 weeks in 80-90% of cases (leaving a scar); however, in 10-20% of those not treated, the infection progresses to septic shock and death.
In some cases, the so-called malignant edema may appear, in which the edema prevails over the eschar, and which occurs with general affectation and a picture reminiscent of erysipelas (although it is more serious).
With regard to inhalational anthrax, the disease (hemorrhagic mediastinitis) progresses rapidly: after 1 to 3 days there is increasing fever, dyspnea (shortness of breath), hemoptysis (blood with cough), hypoxia ( decreased oxygen) and hypotension (lowering of blood pressure), with death occurring within 24 hours in most cases.
The digestive anthrax usually manifests with fever, nausea, vomiting, abdominal pain, bloody diarrhea (sometimes massive) and, sometimes, ascites (liquid in the gut). As we have already reviewed, respiratory and digestive disorders are extremely rare.
In order to reach the diagnosis of this infection, a medical history must first be carried out (with an emphasis, above all, on the profession of the patient and its possible relationship with animals) and a physical examination.
Samples of the lesion should be taken for Gram or fluorescent antibody staining or culture; Sometimes it is advisable, depending on the symptoms, to do more cultures, such as blood (blood cultures), cerebrospinal fluid (it will be positive in case of carbuncle meningitis ), sputum, stool, pleural fluid, etc. In severe cases, a neutrophil leukocytosis is seen in the blood test .
Indirect diagnosis is achieved by serological tests (detection of antibodies).
In addition, we must avoid confusing anthrax with other diseases with similar characteristics, such as plague , staphylococcal anthrax, pneumonia (in the case of lung involvement), tularemia , milkers’ nodule, and so on.
The treatment of choice for anthrax is penicillin; If there is an allergy to this antibiotic, another can be administered, such as erythromycin, tetracyclines or chloramphenicol.
Cutaneous anthrax we have already said that it cures without treatment in most cases, so the prognosis of treated patients is very good. The same does not happen with the other types, in which, even with treatment, there is usually no solution.
For exposed people, there are vaccines. These, however, are being improved today, as they provide only incomplete protection at the moment.
In addition, it is necessary to protect yourself with masks and gloves. Infected animals should be isolated and carcasses incinerated after covering with lime. These should not be quartered or necropsied to avoid sporulation; spores can be tried to destroy with cobalt 60, ethylene oxide, formaldehyde, or bleach.
It is also indicated to vaccinate animals in endemic areas.
Hello Readers, I am Nikki Bella a Psychology student. I have always been concerned about human behavior and the mental processes that lead us to act and think the way we do. My collaboration as an editor in the psychology area of Well Being Pole has allowed me to investigate further and expand my knowledge in the field of mental health; I have also acquired great knowledge about physical health and well-being, two fundamental bases that are directly related and are part of all mental health.