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BAM:CampylobacterReturntoBAMtableofcontents1January2001BacteriologicalAnalyticalManualChapter7CampylobacterAuthors:JanM.Hunt,CarlosAbeytaandTonyTranRevisionHistory:Updatedandrevised:2000-DEC-29MediaInstructionsModifiedon2001-MAR-08IsolationofCampylobacterSpeciesfromFoodandWaterCampylobacterisconsideredbymanytobetheleadingcauseofentericillnessintheUnitedStates(20,26).Campylobacterspeciescancausemildtoseverediarrhea,withloose,waterystoolsoftenfollowedbybloodydiarrhea(7,20).C.jejuni,C.coli,andC.lariaccountformorethan99%ofthehumanisolates(C.jejuni90%).Otherspecieshavebeenassociatedwithhumanillnessinrecentyears(7,17,18,23,26,27).Campylobacterspeciesarehighlyinfective.TheinfectivedoseofC.jejunirangesfrom500to10,000cells,dependingonthestrain,damagetocellsfromenvironmentalstresses,andthesusceptibilityofthehost(4,6,7,20,27).OnlythemesophilicC.fetusisnormallyinvasive.Thermophilicspecies(optimum42°C)suchasC.jejuniareoccasionallyinvasive.Theinfectionsaremanifestedasmeningitis,pneumonia,miscarriage,andasevereformofGuillain-Barrésyndrome(6,20).ThermotolerantstrainsofC.fetusthatgrowat42°Chavebeenisolatedfrompatients(17).Campylobactersarecarriedintheintestinaltractofawidevarietyofwildanddomesticanimals,especiallybirds.Theycanestablishatemporaryasymptomaticcarrierstate,aswellasillness,inhumans.Thisisespeciallyprevalentindevelopingcountries(20).Consumptionoffoodandwatercontaminatedwithuntreatedanimalorhumanwasteaccountsfor70%ofCampylobacter-relatedillnesseseachyear.Thefoodsincludeunpasteurizedmilk,meats,poultry,shellfish,fruits,andvegetables,(1,8-11,17,19,20,22,25,26).C.jejunicansurvive2-4weeksundermoist,reduced-oxygenconditionsat4°C,oftenoutlastingtheshelflifeoftheproduct(exceptinrawmilkproducts).Theycanalsosurvive2-5monthsat-20°C,butonlyafewdaysatroomtemperature(5,8-11,20).Environmentalstresses,suchasexposuretoair,drying,lowpH,heating,freezing,andprolongedstorage,damagecellsandhinderrecoverytoagreaterdegreethanformostbacteria.Olderandstressedorganismsgraduallybecomecoccoidalandincreasinglydifficulttoculture(5,20).Oxygenquenchingagentsinmediasuchasheminandcharcoalaswellasamicroaerobicatmosphereandpreenrichmentcansignificantlyimproverecovery(2,14-16,21,25,28).Campylobactersaremicroaerophilic,verysmall,curved,thin,Gram-negativerods(1.5-5µm),withcorkscrewmotility.Theyoftenjointoformzigzagshapes(20,24).Campylobacterspp.arecurrentlyidentifiedbytestsdescribedbyHarvey(13)andBarretetal.(3).PCRgenusandspeciesidentificationmethodshavebeenpublished(12,18,30).ForadditionalinformationcontactCarlosAbeyta,FDA,PRLNW,Bothell,WA98041-3012.Phonenumber:(425)483-4890.SAMPLEPREPARATIONFLOWCHARTFORVARIOUSFOODSANDWATER(SECTIONC.2.a-h)*forsamplesproducedorprocessed<10dayspreviously.†forfrozensamplesorsamplesproducedorprocessed≥10dayspreviously.A.Equipmentandmaterials1.Balances,6000gcapacity,accurateto0.1g;and200gcapacity,accurateto0.0001g2.Sterilestomacherbags,400and3500mlbagsand400mlfilterbags(otherbagtypesandsizesdescribedinrefs.16,21,and22)3.Whirl-pakbagracksandstainlesssteelbaskets4.Benchtopshaker5.Centrifuge,refrigerated,capableof20,000xg6.Polypropyleneorstainlesssteel250mlcentrifugebottlesand50mlcentrifugetubes,sterile7.Largefunnelswithcheeseclothlinings,sterile(forwholeseafoodandmeatsamplesoriffilterbagsareunavailable)8.Whiteororangegreasepencilstomarkblood-freeagarplates9.50mlsterileconicalc...