传染病学英文版课件：multan-mushtaq

H.I.V.WHATISHIV??“HumanImmunodeficiencyVirus”Auniquetypeofvirus(aretrovirus)InvadesthehelperTcells(CD4cells)inthebodyofthehost(defensemechanismofaperson)Threateningaglobalepidemic.Preventable,managablebutnotcurable.OTHERNAMESFORHIVFormernamesofthevirusinclude:HumanTcelllymphotrophicvirus(HTLV-III)Lymphadenopathyassociatedvirus(LAV)AIDSassociatedretrovirus(ARV)WHATISAIDS???“AcquiredImmunodeficiencySyndrome”HIVisthevirusthatcausesAIDSDiseaselimitsthebody’sabilitytofightinfectionduetomarkedlyreducedhelperTcells.Patientshaveaveryweakimmunesystem(defensemechanism)Patientspredisposedtomultipleopportunisticinfectionsleadingtodeath.AIDS(definition)Opportunisticinfectionsandmalignanciesthatrarelyoccurintheabsenceofsevereimmunodeficiency(eg,Pneumocystispneumonia,centralnervoussystemlymphoma).PersonswithpositiveHIVserologywhohaveeverhadaCD4lymphocytecountbelow200cells/mcLoraCD4lymphocytepercentagebelow14%areconsideredtohaveAIDS.“THEVIRALGENOME”Icosahedral(20sided),envelopedvirusofthelentivirussubfamilyofretroviruses.RetrovirusestranscribeRNAtoDNA.TwoviralstrandsofRNAfoundincoresurroundedbyproteinoutercoat.Outerenvelopecontainsalipidmatrixwithinwhichspecificviralglycoproteinsareimbedded.Theseknob-likestructuresresponsibleforbindingtotargetcell.ModesofHIV/AIDSTransmissionThroughBodilyFluidsBloodproductsSemenVaginalfluidsIntraVenousDrugAbuseSharingNeedlesWithoutsterilizationIncreasesthechancesofcontractingHIVUnsterilizedbladesThroughSexUnprotectedIntercourseOralAnalMother-to-BabyBeforeBirthDuringBirthMythsabouttransmissionNATURALCOURSEOFHIV/AIDSStage1-PrimaryShort,flu-likeillness-occursonetosixweeksafterinfectionMildsymptomsInfectedpersoncaninfectotherpeopleStage2-AsymptomaticLastsforanaverageoftenyearsThisstageisfreefromsymptomsTheremaybeswollenglandsThelevelofHIVintheblooddropstolowlevelsHIVantibodiesaredetectableinthebloodStage3-SymptomaticTheimmunesystemdeterioratesOpportunisticinfectionsandcancersstarttoappear.Stage4-HIVAIDSTheimmunesystemweakenstoomuchasCD4cellsdecreaseinnumber.OpportunisticInfectionsassociatedwithAIDSCD4<500BacterialinfectionsTuberculosis(TB)HerpesSimplexHerpesZosterVaginalcandidiasisHairyleukoplakiaKaposi’ssarcomaOpportunisticInfectionsassociatedwithAIDSCD4<200PneumocysticcariniiToxoplasmosisCryptococcosisCoccidiodomycosisCryptosporiosisNonhodgkin’slymphomaCD4<50Disseminatedmycobacteriumaviumcomplex(MAC)infectionHistoplasmosisCMVretinitisCNSlymphomaProgressivemultifocalleukoencephalopathyHIVdementiaTB&HIVCO-INFECTIONTBisthemostcommonopportunisticinfectioninHIVandthefirstcauseofmortalityinHIVinfectedpatients(10-30%)10millionpatientsco-infectedintheworld.ImmunosuppressioninducedbyHIVmodifiestheclinicalpresentationofTB:Subnormalclinicalandroentgen

presentationHighrateofMDR/XDRHighrateoftreatmentfailureandrelapse(5%vs<1%inHIV)TestingOptionsforHIVAnonymousTestingNonameisusedUniqueidentifyingnumberResultsissuedonlytotestrecipient23659874515AnonymousBloodDetectionTestsHIVenzyme-linkedimmunosorbentassay(ELISA)ScreeningtestforHIVSensitivity>99.9%WesternblotConfirmatorytestSpeicificity>99.9%(whencombinedwithELIZA)HIVrapidantibodytestScreeningtestforHIVSimpletoperformAbsoluteCD4lymphocytecountPredictorofHIVprogressionRiskofopportunisticinfectionsandAIDSwhen<200HIVviralloadtestsBesttestfordiagnosisofacuteHIVinfectionCorrelateswithdiseaseprogressionandresponsetoHAARTUrineTestingUrineWesternBlotAssensitiveastestingbloodSafewaytoscreenforHIVCancausefalsepositivesincertainpeopleathighriskforHIVOralTestingOrasureTheonlyFDAapprovedHIVantibody.AsaccurateasbloodtestingDrawsblood-derivedfluidsfromthegumtissue.NOTASALIVATEST!TreatmentOptionsHAART=highlyactiveanti-retroviraltreatmentAntiretroviralDrugs(HAART)NucleosideReverseTranscriptaseinhibitorsAZT(Zidovudine)Non-NucleosideTranscriptaseinhibitorsViramune(Nevirapine)ProteaseinhibitorsNorvir(Ritonavir)EFFECTIVENESSOFHAARTINREDUCINGMORTALITYHEALTHCAREFOLLOWUPOFHIVINFECTEDPATIENTSForallHIV-infectedindividuals:

CD4countsevery3–6months

Viralloadtestsevery3–6monthsand1monthfollowingachangeintherapy

PPD

INHforthosewithpositivePPDandnormalchestradiograph

RPRorVDRLforsyphilis

ToxoplasmaIgGserology

CMVIgGserology

Pneumococcalvaccine

Influenzavaccineinseason

HepatitisBvaccineforthosewhoareHBsAb-negative

Haemophilusinfluenzaetypebvaccination

Papanicolaousmearsevery6monthsforwomenForHIV-infectedindividualswithCD4<200cells/mcL:

Pneumocystisjiroveci1prophylaxis

ForHIV-infectedindividualswithCD4<75cells/mcL:

Mycobacteriumaviumcomplexprophylaxis

ForHIV-infectedindividualswithCD4<50cells/mcL:

ConsiderCMVprophylaxisPRIMARYPREVENTION:

Fivewaystoprotectyourself?AbstinenceMonogamousRelationshipProtectedSexSterileneedlesNewshaving/cuttingbladesAbstinenceItisthemosteffectivemethodofnotacquiringHIV/AIDS.Refrainingfromunprotectedsex:oral,anal,orvaginal.RefrainingfromintravenousdruguseMonogamousrelationshipAmutuallymonogamous(onlyonesexpartner)relationshipwithapersonwhoisnotinfectedwithHIVHIVtestingbeforeintercourseisnecessarytoproveyourpartnerisnotinfectedProtectedSexUsecondomseverytimeyouhavesexAlwaysuselatexorpolyurethanecondom(notanaturalskincondom)AlwaysusealatexbarrierduringoralsexWhenUsingACondomRememberTo:MakesurethepackageisnotexpiredMakesuretocheckthepackagefordamagesDonotopenthepackagewithyourteethforriskoftearingNeverusethecondommorethanonceUsewater-basedratherthanoil-basedcondomsGLOBALESTIMATES2008ESCALATINGEPIDEMIC!!!Source:WHO/UNAIDS/UNTheMillenniumDevelopmentGoalsReport,2009,p.32andWHO.HIVPREVALENCEINVARIOUSREGIONSSource:UNAIDS,AIDSEpidemicUpdate,December2004.Total=39.4millionSub-SaharanAfricaSouth/South-EastAsiaOceaniaCaribbeanNorthAfrica/MiddleEastWesternEuropeNorthAmericaEastAsiaEurasiaLatinAmerica<42%NEWLYINFECTEDCASESOFHIVINVARIOUSREGIONSSource:UNAIDS,AIDSEpidemicUpdate,December2004Total=4.9million63%ESTIMATEDHIVBURDENINPAKISTAN0.1%oftheadultpopulationinPakistanTotalPopulation(2008)=180,800,000PeoplelivingwithHIV/AIDS(2008)=96,000Women(aged15+)withHIV/AIDS(2008)=27,000ChildrenwithHIV/AIDS(2008)=ndAdultHIVprevalence(%)(2008)=0.1%AIDSdeaths(2008)=5,100ESCALATINGEPIDEMICOFHIVINHIGHRISKGROUPSINPAKISTANPOTENTIALTHREATSINPAKISTAN100,000commercialsexworkerswithpoorsafesexawarenessinthreemajorcitiesEstimated60,000ivdrugusersinpakistan(1in5infectedwithHIV)38,000homosexualsreportedinlahorein200240%of1.5millionannualblooddonorsnotscreenedforHIV20%ofbloodtransfusionscomefromprofessionaldonorswithhighprevalenceofinfectiousdiseasesSignificantlylargenumberofmigrantsandrefugees.UNDER-REPORTINGUntilSeptember2004,only300casesoffull-blownAIDSandanother2300casesofHIVinfectionwerereportedtotheNationalAIDSControlProgram.Thereasonsforunderreportingare:Socialstigmaattachedtotheinfection,LimitedsurveillanceVoluntarycounselingandtestingsystemsLackofknowledgeamongthegeneralpopulationandhealthpractitioners.NATIONALRESPONSETOHIV/AIDSPakistan’sFederalMinistryofHealthinitiatedaNationalAIDSPreventionandControlProgram(NACP)in1987Initsearlystages,theprogramwasfocusedondiagnosisofcasesthatcametohospitals,butprogressivelybegantoshifttowardacommunityfocusThegovernmenthasindicatedintherecentscalingupofitsresponsetoHIV/AIDS,moreneedstobedone.NONGOVERNMENTALORGANIZATIONS54NGOsareinvolvedinHIV/AIDSpublicawarenessandinthecareandsupportofpersonslivingwithHIV/AIDS.Alsoworkingoneducationandpreventioninterventionstargetingsexworkers,truckdriv