Medical Microbiology

404 7 GeneralVirology

afteraninfectionorinsituationsinvolvingahighriskofinfection,e.g.,

toprotectagainsthepatitisBandrabies(locally,bitewound).Table 1. 13

(p. 3 3)andTable8. 7 (rabies,p. 47 0)listthemostimportantvaccines.

Chemotherapy

&Inhibitorsofcertainstepsinviralreplicationcanbeusedaschemo-

therapeuticagentstotreatviralinfections.Inpracticalterms,itismuch

moreimportanttoinhibitthesynthesisofviralnucleicacidthanofviral

proteins.Themainobstaclesinvolvedarethelowlevelofspecificityof

theagentsinsomecases(toxiceffectsbecausecellularmetabolismisalso

affected)andthenecessityofcommencingtherapyveryearlyintheinfection

cycle. &

Problemsofchemotherapy.Asdescribedonp. 381 ,viralreplicationiscom-

pletelyintegratedincellmetabolism.Thevirussuppliesonlythegeneticin-

Table 7. 4 TheMostImportantAntiviralChemotherapeutics

Chemotherapeuticagent Effect/indication

Adamantanamin

(amantadine)

Inhibitionofuncoatingininfluenzaviruses

Acycloguanosine

(acyclovir,Zovirax)

InhibitionofDNAsynthesisinHSVandVZV

Dihydropropoxymethylguanosine

(DHPG,ganciclovir,Cymevene)

InhibitionofDNAsynthesisinCMV

Ribavirin InhibitionofmRNAsynthesisandcapping.

InfectionswithLassavirusandperhapsin

severeparamyxovirusandmyxovirusinfec-

tions

NucleosideRTinhibitors(NRTI) InhibitionofRTinHIV(p.454)

Phosphonoformate

(foscarnet)

InhibitionofDNAsynthesisinherpesviruses,

HIV,HBV

Proteaseinhibitors InhibitionofviralmaturationinHIV

Neuraminidaseinhibitors Inhibitionofreleaseofinfluenzaviruses

AntisenseRNA ComplementarytoviralmRNA,whichit

blocksbymeansofhybridization(duplexing)

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Kayser, Medical Microbiology © 2005 Thieme