传染病学Chapter25 肝炎病毒.ppt

Chapter 25Hepatitis viruses EB virusCMVRubella virusyellow fever virushepatitis viruses Type of Hepatitis VirusesitemHAVHBVHCVHDVHEVClassificationPicorna-viridaeHepadna-viridaeFlavi-viridaeDefective virusHepeviridaeDiameter(nm)274255-653632Nucleic acid+ssRNADsDNA+ssRNA-ssRNA+ssRNA Source ofvirusfecesblood/blood-derivedbody fluidsblood/blood-derivedbody fluidsblood/blood-derivedbody fluidsfecesRoute oftransmissionfecal-oralBlood transfusion,VerticalBloodtransfusion,Verticalfecal-oralChronicInfectionCarcinomaNoNoYesYesYesYesYes------NoNoPrevention inactivated vaccineAttenuated livingvaccine subunit vaccine blood donorscreening;risk behaviormodification Abrisk behaviormodificationensure safedrinkingwaterType of Hepatitis VirusesABCDEBloodtransfusion,Vertical Section 1Hepatitis A virus ( HAV ) HAV:A Picornavirus, now classified as a HeptoVirus, Formerly known as EnteroVirus 72. I. BIOLOGICAL PROPERTIESShape: sphericalSize: 27~32nm Symmetry: icosahedralNon-enveloped+ssRNA, 7500 bp One serotype Hepatitis A Virus Chimpanzee and marmoset are susceptible. Culture: Difficult, no CPE, grow slowly. Stable: resistance to 60℃ 4h, pH=3. inactivated at 100℃ 5min. Source of infection: Patients, subclinical infected Persons. Transmission: fecal-oral route. ( from fecally contaminated water or food ). Children are the most frequently infected group.Pathogenic mechanism: HAV Mouth Intestine Blood LiverPathogenesis Diagrammatic Representation CLINICAL FEATURES Incubation Period: Average 30 days Range 15-50 daysJaundice by age group: <6yrs <10% 6-14yrs 40%-50% >14yrs 70%-80% Outcome: Fulminant hepatitis Acute hepatitis Chronic sequel: None SHANGHAI 1988Over 300,000 people were infected with the virus resulted from eating clams obtained from a polluted water MICROBIAL DETECTION Detect anti-HAV Ig:Acute infection is diagnose