Medical Microbiology

418 8 VirusesasHumanPathogen

cientlysterilizedophthalmologicalinstruments.Theenteralinfectionsare

alsotransmittedbythefecal-oralroute,mainlybycontactratherthanin

waterorfood.Adenovirusesarethesecondmostfrequentdiarrheapathogen

inchildrenafterrotaviruses(p.456f.).

Herpesviruses

&Thevirusesinthisfamilyallfeatureapracticallyidenticalmorphology,

butshowlittleuniformitywhenitcomestotheirbiologyandtheclinical

picturesresultingfrominfections.Onethingsharedbyallherpesvirusesis

theabilitytoreactivateafteraperiodoflatency.

&Theherpessimplexvirus(HSV,twoserotypes)isthepathogenthat

causesavesicularexanthem(feverblisters,herpeslabialis,orgenitalis),

encephalitis,andageneralizedinfectioninnewborns(herpesneonatorum).

&Thevaricella-zostervirus(VZV)causestheprimaryinfectionchickenpox,

whichcanthenrecidivateaszoster(shingles).

&Cytomegalovirus(CMV)infectionsremaininapparentorharmlessin

theimmunologicallyhealthy,butcancausegeneralized,fatalinfectionsin

immunocompromisedindividuals.

&TheEpstein-Barrvirus(EBV)isthepathogenininfectiousmononucleosis

andisalsoimplicatedinlymphomas(includingBurkittlymphoma)andna-

sopharyngealcarcinomas.

&Humanherpesvirus 6 (HHV6)isthepathogenthatcausesthree-day

fever(exanthemasubitum,roseolainfantum).

Humanherpesvirus 8 (HHV8)causestheAIDS-associatedKaposisarcoma.

Diagnosis.Isolation,amplificationculture,ordirectdetectioncanbeused

todiagnoseherpessimplex,varicella-zoster,andcytomegaloviruses;anti-

bodyassayscanbeusedforEpstein-Barr,humanherpes 6 and8,andvari-

cella-zosterviruses;PCRcandetectherpessimplex,varicella-zostervirus,

cytomegalovirus,andhumanherpesvirus6.

Therapy.Effectiveandwell-toleratedchemotherapeuticsareavailableto

treatherpessimplex,varicella-zostervirus,andcytomegalovirus(acyclovir,

ganciclovir). &

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Kayser, Medical Microbiology © 2005 Thieme