通过呼吸道感染的微生物

The microbes infected via respiratory tract,Main pathogenic microbes (Bacteria),Mycobacterium tuberculosis 结核分枝杆菌 Streptococcus pneumoniae肺炎链球菌 Corynebacterium diphtheriae白喉棒状杆菌 B. pertusis百日咳鲍特菌,Main pathogenic microbes (virus),Influenza virus流行性感冒病毒 Varicella-Zoster virus, VZV水痘-带状疱疹病毒 Mumps virus 腮腺炎病毒 Measles virus麻疹病毒 Rubella virus风疹病毒,Other main pathogenic microbes,Mycoplasma pneumoniae 肺炎支原体 Chlamydia pneuminiae 肺炎衣原体,1、 Mycobacterium tuberculosis,acid-fast rods capsulate obligate aerobe doubling time about 1824h Lowenstein-Jensen medium variation,resistance drying acids and alkalies dyes (malachite green) sensitive moist heat 70% ethyl alcohol ultraviolet light,1) Biologic properties:,Mycobacterium tuberculosis,2) Pathogenicity,capsule lipids cord factor(索状因子) , damage mitochondria membrane phosphatides(磷脂), tubercules sulfatides(硫酸脑苷脂), inhibit phagosome-lysosome fusion waxes(蜡质D) adjuvant proteins tuberculin,Infectious reservoirs patients,carriers transmitted ways: respiratory tract 、alimentary tract、skin pulmonary tuberculosis primary infection secondary infection extra-lung infection,3) Diseases caused,M.Tuberculosis in lung,4) Immunity,infectious immunity T cell-mediated immunity immunity and hypersensitivity Koch phenomenon,5) Tuberculin Test,principium reagent old tuberculin, OT purified protein derivative, PPD method significance,prevention vaccination: BCG treatment rifampin (利福平) isoniazid (异烟肼) ethambutol(乙胺丁醇) streptomycin(链霉素),6) prevention & treatment,2、 treptococcus pneumoniae,Gram-positive lancet-shaped In pairs capsulate autolysis,1) Biologic properties:,Capsule,anti-phagocytic serotyping,2) Pathogenicity,Autolysis - identification,Bile,peptidoglycan,cell membrane,teichoic acid -choline,autolysin,lobar pneumonia(大叶性肺炎) particularly young and old after damage to upper respiratory tract e.g. following viral infection Meningitis(children)(脑膜炎） otitis media(中耳炎）,3) Diseases caused,3、Corynebacterium diphtheriae,rod shape Gram positive metachromatic granule aerobe growth in Loefflers medium tellurite agar,1) Biologic properties:,Corynebacterium diphtheriae,Corynebacterium diphtheriae,metachromatic granule,Diptheria toxin,B binds to host cell A inhibits protein synthesis inactive elongation factor 2 coded by b-bacteriophage tox gene,2) Pathogenicity,Diphtheria,infection upper respiratory tract (pharynx) pseudomembrane chocking bacteria do not spread systemically,菌,鼻咽部繁殖,局部炎症：假膜,早期致死,外毒素,心肌炎 软腭麻痹 声嘶 肾上腺功能障碍,晚期致死,入血,3) Diseases caused,This child has diphtheria resulting in a thick gray coating over back of throat. This coating can eventually expand down through airway and, if not treated, the child could die from suffocation CDC,4、Influenza virus,type A antigenic highly variable worldwide epidemics (eg. 1918) type B antigenic change somestimes epidemics type C antigenic stable mild illness,Structure,core (-)ss RNA, separated segments seven（type C)or eight (type A, B) helical nucleoprotein (NP) envelope: 2 layers M1 protein: coded by virus lipid bilayer membrame: from host hemagglutinin (HA) neuraminidase (NA),1) Biologic properties:,hemagglutinin (HA) absorption, penetration hemagglutination antibody to the HA protein (HIAb) neutralize the virus prevent infection neuraminidase (NA) release,spread antibody to the NA protein slow the spread of the virus & no protection,antigenic drift minor changes in HA or NA variance ratio1% point mutation Limited spread antigenic shift major changes in HA variance ratio:20%50% new subtype Worldwide spread,variation,2) Pathogenesis,person to person via small particle aerosols via contact infects the epithelial cells of the respiratory tract uncomplicated influenzapneumonia major causes of influenza-associated death bacterial pneumonia cardiac failure,prevention vaccine:multivalent two strains of influenza A and one of influenza B treatment amantadine Chinese traditional medicine IFN-alfa,3) prevention & treatment,5、Mycoplasmal pneumoniae,primary atypical pneumonia via aerosolized droplets in confined populations families, schools, army barracks in persons 5-20 years of age,Laboratory Diagnosis Culture Sputum or throat washings ELISA PCR Treatment tetracyclines,6、Chlamdia pneumoniae,pathogenesis via respiratory droplets ca