Tularemia

Overview tularemia (tularemia) called tularaemia disease or deer fly fever, is a zoonosis of natural foci of sexually transmitted diseases. The main clinical manifestations are fever, enlarged lymph nodes, skin ulcers, conjunctival hyperemia, ulcers, respiratory and digestive tract and lead to inflammation. Of the disease in 1907 by Mortin in the United States found that in 1921 named Francis tularaemia disease. China's Qinghai, Xinjiang, Tibet, Heilongjiang and other provinces have reported cases. Rafah pathogenic soil bacillus is a small (0.3 ~ 0.7 × 0.2μm) no activities of the ball Gram-negative bacteria, and could in the medium with pleomorphic, within the organization can be formed Clostridium. In general growth medium is not easy, a commonly used serum glucose and serum homocysteine 1 medium egg yolk medium. Bacteria type can be divided into : 1. American variant (A), glycerol can decomposition of rabbits strong toxicity; 2. European varieties (B), glycerol decomposition of rabbit poisoning weak. The fungus has three antigens : ?٠polysaccharide antigen, can speed recovery in patients allergic hairstyle; ?ڠcell wall and membrane, which is the original, autoimmune and endotoxin; ?۠protein antigen may have delayed hypersensitivity. Francisella bacilli to survive in nature is quite strong, but the physical and chemical factors is not strong resistance, heating 55 ~ 60 ° C, 10 minutes of death, the ordinary disinfectants can be inactivated, but the arrival of warm, dry stronger resistance. The corpses survive 133 days. Epidemiology (1) the source of infection of nature over 100 species of wild animals, farm animals, birds, fish and amphibians have unearthed separation tularaemia. But the main source of infection is the hare, voles. 1 -2 lamb and sheep-year-old David after infection, can also be used as the source of infection. Man-to-man transmission is not reported. (2) The main mode of transmission for direct contact, insect bites and gastrointestinal infection intake. Aerosol can from respiratory or eye by combining membrane enter the body. The bacteria transmission power and no damage through the skin or mucosa, human hunting, agriculture, labor, Field activities and handle the animals to pay attention to. (3) susceptibility of different age groups, gender and occupation of the population are susceptible. Hunters, slaughtering and meat processing fur, deer mice feeding, laboratory workers and peasants and herdsmen from contact with more opportunities, infection and the incidence is higher. The disease infected more recessive disease can have lasting immunity, and occasionally infected. The disease can be popular throughout the year, more cases have occurred in the summer. Principle and the incidence pathological changes pathogens by different channels after invading the human body through the lymphatic vessels entered a nearby lymph node, caused lymph node inflammation and swelling of lymph nodes in the partial reproduction of bacteria were part of the eradication of phagocytes, part from the lymph nodes into the blood circulation, invasive body of the organizations, liver, spleen, lymph nodes, Bone marrow reticuloendothelial system such as bacteria particularly perturbed over. Francisella bacilli in organizations large growth and reproduction, and releases toxins within, leading to the onset of clinical symptoms. Clinical symptoms after the resumption, and some patients in long-term bone marrow or lymph nodes infected. Pathology revealed lymph node congestion, swelling, microscopic examination found serous infiltration and lymph tissue necrotic lesions centers and suppuration, known as the primary ulcer. With the progress of the disease or chronic, liver, spleen and lymph node inflammation occurred secondary, the performance of the tuberculosis - like granuloma formation. Granuloma from epithelial cells, peripheral lymphocytes, plasma cells and neutrophils siege, centers often necrosis and suppurative. But no bleeding granuloma is different from the important signs of plague.