Medical Microbiology

464 8 VirusesasHumanPathogen

Diagnosis.Intheacutestage,arenavirusescanbeisolatedfromthepatient’s

blood.Postmortemisolationisbestdonefromlivertissue.Inthehemorrhagic

fevers,especiallyLassafever,thebloodishighlyinfectiousandhandlingit

requiresproperprecautionsandutmostcare(aerosolformation!).Isolation

ofthevirusisrelativelyeasyincellcultures.Forreasonsofsafety,onlyspecial

high-securitylaboratoriesarequalifiedtohandletheseorganisms(e.g.,atthe

CentersforDiseaseControlandPreventioninAtlanta,GA,USA).

Serodiagnosisisalsofeasibleusingstandardserologicaltechniques.

Epidemiologyandprevention.Allarenavirusesareendemictorodentsand

aretransmittedtohumansbytheseanimals.

Nospecificimmunoprophylactictoolshavebeendevelopedforanyof

theseviruses.Asfarasexposureprophylaxisisconcerned,itmustberemem-

beredthattheLCM,Junin,andMachupovirusesarenottransmittedamong

humans,butthattheLassavirusistransmittedbythisroute.Themoststrin-

gentprecautionsarethereforecalledforwhentreatingLassa patients.

Healthcarestaffmustwearspecialclothingandfacemasksandspecialre-

duced-pressureplastictentsarerecommendedaspatientcubicles.The

therapeutictoolsavailablefortreatmentareribavirinandhumanimmuno-

globulin.

Paramyxoviruses

&Thisfamilyincludesthegenera:

&Parmyxoviruswiththeparainfluenzaviruses.

&Rubulaviruswiththemumpsvirus.

&Morbilliviruswiththemeaslesvirus.

&Pneumoviruswiththerespiratorysyncytialvirus(RS).

&Nonclassifiedparamyxoviruses(Hendra,Nipah).

Theclinicalmanifestationsincluderespiratoryinfections(parainfluenza,

pseudocroup,mumps,RS,Nipah,Hendra),parotitis,andinfectionsofother

glandularorgans(mumps),exanthem(measles),andCNSinfections(mumps,

measles,Nipah,Hendra).

Prevention:livevaccinesareusedtoprotectagainstmeaslesandmumps;

noimmunoprophylactictoolsareavailableagainsttheotherparamyxo-

viruses. &

Pathogen.ThefamilyParamyxoviridaeisaheterogeneousone,bothinits

biologyandpathogenicproperties.Itisdividedintotwosubfamilies:

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Kayser, Medical Microbiology © 2005 Thieme