Anthrax is a zoonotic infectious disease caused by Bacillus anthracis.Anthrax originally herbivores (sheep, cattle, horses, etc.) of infectious diseases, people infected through contact with these sick animals and their products or eating the meat of sick animals.Mainly on anthrax clinical local skin necrosis and specificity of the black scab, or acute infection of the lung, intestinal and meningeal, sometimes accompanied by Bacillus anthracis sepsis.
Anthrax - pathogenAnthrax anthrax bacillus (Bacillus anthracis) is an aerobic or facultative anaerobic, thick bacilli without flagella, length 4 ~ 8μm width 1 ~ 1.5μm; cell ends flat cut was a long chain of bamboo-shaped arrangement of leather Gram staining is positive. Capsule form and with strong pathogenicity in the human body, non-toxic strains do not produce the capsule. Bacillus anthracis life and strong growth in normal medium.Bacillus anthracis in the human and animal body the capsule, spore formation in vitro inappropriate. Resistance of the pathogen propagules with common bacteria at 56 ° C for 2 hours, 75 ° C for 1 minute to kill. Commonly used concentration of the disinfectant can kill quickly. In vitro unsuitable environment can form oval spores. The resistance of Bacillus strong, long-term survival in natural conditions or in the pickled meat, can survive in soil for decades, can survive 90 years in the fur products, exposure to direct sunlight for 100 hours, boil 40 minutes, 140 ° C three hours of hot, 110 ° C high-pressure steam 60 minutes, and soaked in 10% formalin solution for 15 minutes, new with carbolic acid solution (5%) and 20 percent bleach solution for more than a few days before spore kill. The pathogen virulence.
Of antigen of Bacillus anthracis capsular antigen, bacterial antigen, four kinds of protective antigen and Bacillus antigen. Capsular antigen is a peptide, can inhibit the opsonization, and the invasiveness of the bacteria, antiphagocytic; somatic antigen Although there is no toxicity, but with species-specific; protective antigen with strong immunogenicity; Bacillus antigens are immunogenic and serological diagnostic value.Bacillus anthracis breeding physical secretion of anthrax toxin, this toxin by Part I factor (edema factor, EF), Part II factors (protective antigen, the PA) and Part III factor (lethal factor, LF), the composite polymer. The three components of individual injected animals, no toxicity, but the protective antigen plus edema factor or lethal factor can be caused by edema, necrosis, or animal death.
Anthrax - an overview of the content
Anthrax of a plant disease. Anthrax occurs in warm, humid areas, infect a variety of herbaceous and woody plants, some conidia disk the fungi (usually barbed plate spp [Colletotrichum] or plate length spp [Gloeosporium]) due. The symptoms are sunken spots appear in a variety of colors in the leaves, stems, fruit or flowers. The spots often extend a result of wilting, withering, or tissue death. The late 1970s in North America to identify a new type of anthrax ─ ─ dog wood anthrax. With other types of anthrax, this type is more common in cool weather conditions, Dogwood anthracnose first appeared in northwestern North America, the Pacific, and then quickly spread to the eastern United States, finally led to the growth of natural mountain dog wood into piece death. Until 1991 the types of pathogens - devastating the seat plate spore (Disculadestructiva), have been described. The methods of prevention and treatment of anthrax is the remove disease Ministry. Disease-free seed and resistant varieties, application of fungicidal agents to control insect and mite pathogenic fungi in the spread between the plants.
Anthrax is an acute infectious disease of herbivores caused by Bacillus anthracis. A zoonotic acute infectious diseases. Infection due to contact with sick animals and their products or meat eating sick animals. Clinical mainly manifested as skin necrosis, ulceration, eschar and surrounding tissue, extensive edema and toxemia symptoms, and occasionally lead to acute infection of the lung, intestine, and meninges, and can be associated with sepsis.
Bacillus anthracis has four kinds of antigens: (1) capsule peptide antigen, anti-phagocytosis. (2) bacterial polysaccharide antigen, a kind of specificity. ③ spore antigens. The ④ protective antigen, a protein that is an integral part of the anthrax toxin. There are three kinds of strains produce toxins, protective antigen, edema toxin, lethal factor. Anthracis (anthrax) is a zoonotic infectious disease caused by Bacillus anthracis. The original Department of herbivores (sheep, cattle, horses, etc.), infectious diseases, people infected through contact with these sick animals and their products or eating the meat of sick animals. The major clinical manifestations of local skin necrosis and specificity of the black scab, or the performance of the acute infection of the lung, intestinal and meningeal, sometimes accompanied by Bacillus anthracis sepsis.
Anthrax - epidemiology
Anthrax
(A) anthrax source of infection
Sick herbivores such as cattle, sheep, horses, camels, pigs and dogs, they may swallowed Bacterial contamination of food and get sick. Direct or indirect contact with secretions and excretions can infect. Sputum, feces, and lesions of anthrax exudate is contagious.
(B) of anthrax transmission routes
A. Wound through the skin and mucous membranes due to direct contact with the germs of the disease. Bacteria poison strong direct invasion of the intact skin.
Two. By inhalation with anthrax dust, droplets of the disease.
3. Infected by ingestion of contaminated food or drinking water.
(C) of the population susceptibility was susceptible to SARS, but more common in farmers and herdsmen, slaughtering, fur processing, veterinary and laboratory personnel. Incidence or not closely related to the body's resistance.
(D) anthrax epidemic characteristics have a certain relationship between animals and humans disease caused by factors of livestock epidemic and the factors of the popular crowd. The disease throughout the world occur, the incidence of multi-summer.
Plant anthrax when spores enter the skin of a certain number of rupture, the ingestion of the gastrointestinal tract or inhalation, and body resistance weakened pathogens by capsular protection, first in the local breeding, to produce large amounts of toxins, leading to tissue organ hemorrhagic infiltration, necrosis and severe edema, the formation of primary cutaneous anthrax, intestinal anthrax, pulmonary anthrax. When the lower body resistance when pathogens rapidly along the systemic spread of the lymphatic and blood circulation, the formation of sepsis and secondary meningitis. Cutaneous anthrax because of the role of ischemia and toxins, dermal nerve fiber degeneration, the lesion is often no obvious pain. Such as human health, and into the body of Bacillus less or low virulence, and you can not incidence or latent infection.
The pathogenicity of Bacillus anthracis and its toxins in the synergy of the components related to. Anthrax toxin can directly damage the microvascular endothelial cells, so that the increased permeability of the blood vessel wall, leading to effective hypovolemia; coupled with the acute infection, the release of a number of biologically active substances, so that the expansion of small blood vessels, increased vascular permeability, reducing the tissue perfusion; the toxins intimal injury, activate the coagulation system and release of tissue thromboplastin enzyme material, blood hypercoagulable state, the DIC and septic shock are more common in anthrax. In addition, Bacillus anthracis can plug capillaries, tissue hypoxia ischemia and microcirculation, thrombus formation.
Anthrax - Clinical manifestationsLeaves anthrax incubation periodGenerally 1 to 5 days, there are as short as 12 hours and as long as two weeks.Cutaneous anthrax:About 98% of the exposed parts of skin lesions are more common in the face, neck, shoulders, hands and feet. First as a rash or pimples the next day with a blister, containing a yellowish liquid, the surrounding tissue hard and swollen. 3 on the 4th center showing hemorrhagic necrosis slightly sinking, surrounded by groups of small blisters, edema continue to expand. 5 to 7 days necrotic areas of ulceration into shallow ulcers, blood exudate to form a hard and black like charcoal block eschar, granulation tissue formation (ie, anthrax carbuncle) under the scab. Eschar necrotic area diameter of the surrounding skin infiltration and edema range. Local peripheral nerve compression and pain not, and a slight itching, abscess formation, which is the characteristics of the anthrax. Later with edema, black scab in 1 to 2 weeks off, gradually healed into a scar. The onset of fever (38 ~ 39 ° C) headache, joint pain, aches and discomfort as well as the local lymph nodes and spleen enlargement and so on. A few cases, local black scab formation was massive edema (malignant edema), its rapid expansion, can cause large areas of necrosis, common in the loose tissue of the eyelids, neck, thigh and hand. Systemic symptoms are severe, delaying treatment and poor prognosis.
Pulmonary anthrax:Pulmonary anthrax as primary, secondary cutaneous anthrax. Acute onset, the light, chest tightness, chest pain, general malaise, fever, cough, a little mucus in sputum with blood. In severe cases, chills, fever onset, due to the mediastinal lymph node swelling, bleeding and bronchial compression caused by respiratory distress, gas Jichuan Ming, coughing, cyanosis, blood sputum. Lungs could be heard only scattered small moist rales or signs of pleurisy. Pulmonary signs and the disease often do not match. X-ray, see the mediastinal widening, pleural effusion, and lung inflammation.
Intestinal anthrax:Intestinal anthrax may manifest as acute enteritis or acute abdomen-type. Acute enteritis incubation period of 12 to 18 hours. The same food who have the disease, similar to food poisoning. Symptoms of varying severity, sudden onset of nausea, vomiting, abdominal pain, diarrhea. Acute abdomen in patients with symptoms of systemic poisoning is severe, persistent vomiting and diarrhea, the row of bloody stools, abdominal distension, abdominal pain, tenderness, or was peritonitis signs, often complicated by sepsis and septic shock. If not treated can often lead to death.Meningeal anthrax:Meningeal anthrax are mostly secondary. Rapid onset, severe headache, vomiting, coma, convulsions, obvious meningeal irritation, cerebrospinal fluid mostly bloody, a few yellow, the pressure increased, the number of cells increased. The rapid progression of the disease, often misdiagnosed lack of timely treatment and death.
