Viralhepatitis
DefinitionViralhepatitisisakindofinfectiousdiseasecausedbyhepatophilicviruswithliverdamageasthemainperformance.
FivecommonlyrecognizedvirusesthatcausehepatitisinhumansHAVHBVHCVHDVHEV
Classification-Routeoftransmission1.Fecal-oralpathwayHAVHEVAcutehepatitis2.ExtraintestinalpathwayHBVHCVHDVChronicinfectionlivercirrhosislivercancer
EtiologyHAVInthestoolofpatientsintheacutephase,especiallyinthelatentphaseResistanceisstrong,canwithstand56℃,30minutes,roomtemperatureforaweek.25°indryfecescansurvive30days,inshellfish,sewage,freshwater,seawater,soilcansurviveforseveralmonths.
EtiologyHBV
HBV--antigen-antibodysystems1.HBsAganti-HBssystem2.HBcAganti-HBcsystem3.HBeAganti-HBesystem
1.HBsAganti-HBssystemHBsAgSignsofHBVinfectionHasantigenicity,butitselfisnotinfectiousanti-HBsAppearafterthetheclinicalsymptomshavedisappearedItsappearancemarkstherecoveryofHBVinfectionTheonlyprotectiveantibodyafterinfectionofHBV,canresisthomotypevirusinvasion
2.HBcAganti-HBcsystemHBcAginfectiousandantigenicHBVreplicationindicatorsanti-HBcIgM:RecentHBVinfectionorchronicactivityIgG:Acuteinfectionoccurs6to12monthsafteronsetandlastsforseveralyearsorforlifeandisamarkofpreviousinfection
3.HBeAganti-HBesystemHBeAgHBVreplicationindicatorsinfectiousanti-HBeoccurslateintherecoveryperiodConversionfromHBeAgtoanti-HBEoftenresultsinincreasedclinicalsymptoms
SummaryforHBVHBsAg:SignsofHBVinfectionAnti-HBsAg:HepatitisBiscuredandprotectiveantibodiesareproducedHBcAg:HBVreplicationindicatorsAnti-HBcAg:PreviousorpresenthepatitisBvirusinfectionHBeAg:HBVreplicationindicatorsAnti-HBeAg:HepatitisBvirusreplicationislow
EtiologyHCVThemaincauseofhepatitisafterbloodtransfusion
Epidemiology--SourceofinfectionHepatitisA,E:AcutepatientsandsubclinicalinfectionHepatitisB,C,