醫(yī)學微生物學課件：13 人畜共患菌

1、Animal Source Bacteria(動物源性細菌)Zoonosis (動物源性疾病) are human diseases caused by organisms that are acquired from animals. There are bacterial, viral, fungal, and parasitic zoonosis. Some zoonotic organisms are acquired directly from the animal reservoir（宿主）, whereas others are transmitted by vectors, s

2、uch as mosquitoes, fleas, or ticks.Zoonosis (動物源性疾病)from animalsdirectly from the animal reservoirIndirectly by vectors, such as mosquitoes, fleas, or ticks There are bacterial, viral, fungal, and parasitic zoonosisZoonosisBacillus anthracis (炭疽芽胞桿菌) Yersinia pestis (鼠疫耶爾森菌) Brucella abortus ( 牛布魯菌)

3、Brucella (布魯菌屬) Brucella (布魯菌屬)G-, small rodsfacultative intracellular pathogens (兼性胞內(nèi)寄生桿菌)Pathogenic strains for human beingB. melitenisis(羊布魯菌)B. abortus(牛布魯菌)B. suis(豬布魯菌)Infectious routesMucous membranes-(ingestion/inhalation routes, or through the conjunctiva. ), such as, ingestion of milk or m

4、ilk products. Skin-contact with infected tissues of animalsPathogenesisPathogenic factorsCapsuleHyaluroniase (透明質(zhì)酸酶)Anti-phagocytosis, intracellular pathogens , repeat bacteremia, lesions of many organsenterotoxinFever, hypersensitivity reactionDiseaseAnimals: abortionBrucellosis is primarily a dise

5、ase of animals and it affects organs rich in the sugar erythritol(赤藻糖醇) (breast, uterus, epididymis副睪, etc.). The organism localizes in these animal organs and cause infertility(不孕 ), sterility(不育), mastitis(乳腺炎), abortion or resides as carriage. Human being: Brucellosis (undulant fever)Humans in cl

6、osed contact with infected animals are at risk of developing undulant fever.The symptoms in brucellosis are due to the presence of the organism and appear 2 - 4 weeks (sometimes up to 2 months) after exposure. B. melitensis(羊布魯菌 ) is the cause of most severe prolonged recurring disease. The intracel

7、lular persistence of bacteria results in granuloma(肉芽腫) formation in the reticuloendothelial system organs and tissue damage due to hypersensitivity reactions, mostly type-IV.The bacteria are engulfed by neutrophils and monocytes and localize in the regional lymph nodes, where they proliferate intra

8、cellularly. The organisms migrate to other lympho-reticular organs (spleen, bone marrow, liver, testes) producing granulomas and/or micro abscesses.Symptoms include fever, chills, sweats, fatigue(疲勞), myalgia(肌痛), profound muscle weakness, and anorexia(厭食). Prevention and TreatmentThe control measur

9、es include animal vaccination and avoidance of infected material.Prolonged treatment with rifampin, which penetrates cells with streptomycin or tetracyclin is used to treat human Brucella infections. Bacillus 芽胞桿菌屬aerobic, G+ spore-forming large bacillusPathogenic bacilliB. anthracis (炭疽芽胞桿菌)zoonosi

10、s-Anthrax (炭疽)B. cereus (蠟樣芽胞桿菌) food borne infectionenterotoxinVomitive form caused by heat stable enterotoxin Diarrheal formcaused by heat labile enterotoxin B. Anthracis (炭疽芽胞桿菌)The first bacterium(1877), first attenuated live vaccineSpores are in nature (soil, animal coat)Infections by wound or

11、inhalation(一)Biological characteristicsMorphology Pure culture, gram stain, stained blood smearcultureaerobicColonies:R type curled edge(under CM)Ground glass(毛玻璃) appearance(二)Pathogenesis and immunityPathogenic factorscapsuleexotoxins (A-B type toxin)protective antigen, PA (保護性抗原)- antitoxinedema

12、factor, EF (水腫因子)lethal factor, LF (致死因子)Diseases- anthraxCutaneous anthrax (95%)Gastrointestinal anthrax (5%) Pulmonary anthrax (very rare)4d5d6d8d11d13d皮膚炭疽(三) Diagnosis and prevention & treatmentdiagnosisSmear, microscopic examinationCulture串珠試驗(+)Prevention and treatmentvaccinepenicillin二.Yersin

13、ia 耶爾森菌屬G- small bacillusPathogenic Yersinia for human beingYersinia pestis 鼠疫耶爾森菌Y. enterocolitica 小腸結(jié)腸炎耶爾森菌Y. pseudotuberculosis 假結(jié)核耶爾森菌Yersinia pestis 鼠疫耶爾森菌G-, short and wide rodsYersinia pestis 鼠疫耶爾森菌characteristicsenterobacteriaceaefacultatively aerobicfacultative intracellular pathogens (兼性細胞

14、內(nèi)寄生), bipolar staining (兩端濃染)Yersinia pestis grows well on most standard laboratory media, after 48-72 hours, grey-white to slightly yellow opaque raised, irregular “fried egg” morphology; alternatively colonies may have a “hammered copper” shiny surface Yersinia pestis 鼠疫耶爾森菌Ag and pathogenic facto

15、rsF1 Ag (fraction 1 Ag) : Capsule Ag, protective AgV/W Ag: coded by a plasmid, be associated rapid proliferation and septicemia.Yersinia outer membrane proteins(Yop):A group of 11 proteins, which are coded by plasmids, are essential for rodent pathogenesis and are responsible for cytotoxicity, inhib

16、ition of phagocyte migration and engulfment and platelet aggregation.endotoxin murine toxin(MT) : blood vessel, toxoid, one is lethal for mice in amount of 1mg.Infectious source and routesCarrier: rodent(嚙齒動物) fleasBy bite (mice-flea-human being)by contact with infected animalsby respiratory tractDi

17、seasePlaque (鼠疫)- black deathbubonic plague (腺鼠疫)Septicemia plague (敗血癥型鼠疫)pneumonic plague (肺鼠疫): 100%mortalitySeveral bacteria can cause diseasePlague patient displaying a swollen axillary lymph nodePrevention and treatmentDestroy mice and fleaHospitalization and strict isolation are the ruleVacci

18、ne- murine toxoidAntibiotics - 慶大霉素、鏈霉素或強力霉素 Other bacteriaNonfermentative gram-negative bacilli Pseudomonas aeruginosa (銅綠假單胞菌) Pseudomonas (假單胞菌屬)G- bacillus, polar flagellastrictly aerobicwater-solubility (水溶性) pigment strong resistance, resistance to various antibiotics pathogenesisVirulent fact

19、orsinvasivenesspili, micro-capsuleproteinasestoxinsendotoxinexotoxin A (similar to Diphtheria toxin)pathogenesisOpportunistics pathogen-Nosocomial infections (院內(nèi)感染) fatal pneumonia-especially in Cystic fibrosis (囊狀纖維化)patients Cutaneous infections-in burn, wound septicemia (敗血癥)urinary tract infecti

20、on-as a result of catheter use or surgery Helicobacter pylori, HP (幽門螺桿菌)2005年10月3日，巴里馬歇爾（右）與羅賓沃倫得知自己獲得2005年諾貝爾生理學或醫(yī)學獎后，舉杯互相慶賀。 1997年9月2日，沃倫（右）和馬歇爾在澳大利亞珀斯市 Helicobacter pylori, HP (幽門螺桿菌)G-, curved or spiral shaped , S, or gull-wing shaped, multiple flagella at a polar and is actively motileHelicoba

21、cter pylori, HP(幽門螺桿菌)G-Gastric biopsy (Giemsa stain)p226G-, spiral shaped , S, or gull-wing shaped , polar flagellaHelicobacter pylori, HP (幽門螺桿菌)Urease(+), oxidase and catalase (+)Diagnosis vivo tests for urease activity urea（C14-labeled urea）urease（脲酶） NH3+ CO2* Helicobacter pylori, HP (幽門螺桿菌)Chr

22、onic gastritis, ulcers, gastric carcinomaBacteria infected through respiratory tractBacteria infected through respiratory tractLegionella (軍團菌屬)L. pneumophila (嗜肺軍團菌)Haemophilus (嗜血桿菌屬)H. influenzae (流感嗜血桿菌)Bordetella (鮑特菌屬)B. pertussis (百日咳鮑特菌)Legionella pneumophila (嗜肺軍團菌)facultative intracellular

23、 pathogens (兼性細胞內(nèi)寄生), G- bacilus, stain poorly by Gramp 229Legionella pneumophila (嗜肺軍團菌)Be ubiquitous in warm moist environments, aerosol inhalation (氣溶膠吸入) Virulent factorspili, flagellum, micro-capsule, enzymesenterotoxin, cytotoxindisease-legionellosis (軍團病)diagnosisSmear, staining and microscop

24、yfluorescence Ab testSilver staindiagnosiscultureBCYE agar（活性炭-酵母浸出液瓊脂, buffered charcoal-yeast extract agar）Antibody testsBCYE(3-5d)二. Haemophilus influenzae (流感嗜血桿菌)Biological characteristicsG- small bacillus, pleomorphic (多形性)can be grown on chocolate agar (heated blood) and requires factor and f

25、actor (hemin ) satellite phenomenon (衛(wèi)星現(xiàn)象)二. H. influenzae (流感嗜血桿菌)Virulent factorspili, capsule, IgA proteinase, LOS(脂寡糖)Disease-depend on bacterial capsulePrimary infection-suppurate infection (化膿性感染, caused by bacteria with capsule) Secondary infection- Endogenous infection (內(nèi)源性感染, without capsule )三. Bordetella pertussis (百日咳鮑特菌) Biological characteristicsG- small bacillus, strictly aerobic, B-G media (bordet-Gengou media, 鮑-金培養(yǎng)基)Virulent factors-capsule, pili, endotoxin etcPertussis toxin (pertussigen, PT,百日咳毒素)Adenylcyclase toxin (腺苷酸環(huán)化酶毒素)Tracheal cytotoxin (氣管細胞毒素)Dermon