HomeMenuNotifiableDiseasesPublicationsEPI-InsightTopicsA-ZCOVID-19(NovelCoronavirus)SearchSearchCOVID-19InformationHomeA-ZMicrobiology/AntimicrobialResistancemcrpositiveEnterobacteriaceaeCaseDefinitionmcr-positiveEnterobacteriaceae*infectionorcolonisationClinicalcriteriaNotrelevantforsurveillancepurposes.LaboratorycriteriaTheidentificationofEnterobacteriaceae*carryingoneormoreofthemcrfamilyofgenesfromanyspecimen,whetheradiagnostic(invasive,non-invasiveinfectionorcolonisation,alsoknownascarriage)orscreeningspecimen(colonisation,alsoknownascarriage).mcrpositiveEnterobacteriaceaearebacteriaofthefamilyEnterobacteriaceaeconfirmedtohaveoneofthefamilyofmcrgenes.Confirmationofthepresenceofthemcrgeneshouldbebyareliablemethod,suchasamolecularmethod.EpidemiologicalcriteriaNotrelevantforsurveillancepurposes.Caseclassification-Possiblecase:Notapplicable-Probablecase:Notapplicable-Confirmedcase:AnypersonmeetingthelaboratorycriteriaOutbreakAnoutbreakofmcr-positiveEnterobacteriaceaeisdefinedastwoormoreconfirmedcasesofmcr-positiveEnterobacteriaceae(causinganyofinvasiveornon-invasiveinfectionorcolonisation)thatarelinkedepidemiologicallyintimeandplace.Note:Giventhatchainsofmcr-positiveEnterobacteriaceaetransmissionaregenerallysilentatthetimeoftransmissionandmayinvolvemultiplespeciesofEnterobacteriaceae,assessmentoflinkageischallenging.Ifthereisanyconcern,anoutbreakcontrolteamshouldbeconvenedtoassesswhetherthereisanoutbreakandwhatactionisrequired.Definitionsmcrgene:mcrisanacronymformobilisedcolistinresistance.ThemcrgeneencodesfortheproductionofanenzymewhichalterstheGram-negativebacterialcellmembrane,sothattheantimicrobialcolistincannotdamageit,renderingcolistininactiveandenablingthebacteriatobecomeresistanttocolistin.Themcrgeneiscarriedonaplasmid,whichisamobilegeneticelementreadilytransferrablebetweenbacteria. Enterobacteriaceae:Thisisafamilyofbacteria.DuetorecenttechnicalchangesinbacterialclassificationthestrictmeaningofthetermEnterobacteriaceaehasbeennarrowed.ThetermEnterobacteralesn