Download Spread of Porcine Epidemic Diarrhea virus

SwineHealthMonitoringProject
PEDvUpdate
SpreadofPorcineEpidemicDiarrheavirus
Recently,PEDvhasspreadtofarͲreachingpigpopulationsincludingHawaiiandUkraine.
Duringthesummer,Hawaiitightenedbiosecuritybyimpartingmorestrictimportrequirementsforlivepigs.Therequirements
includedPEDvtestingandabanonallinfectedpigs,butthoserequirementsaswellasanoceanofseparationdidnotprevent
transmissiontoa150ͲheadfarmontheislandofOahu.InthecontinentalUS,manyroutesoftransmissionofPEDvhavebeen
suspectedoridentifiedbyepidemiologicstudiesincludingfomitessuchasmarket,cullanimal,andcarcassdisposaltransportation
methods;wildlifeasamechanicalvector,porcineplasmaandotherfeedproducts;andaerosoltransmission.Itisstillunclearhow
PEDventeredHawaii,butitisunlikelythatwildlifeoraerosolizedvirusfromthemainlandwasthesource.Thestringent
requirementsforimportingshouldhavehelpedtoreducetheriskoftransmissionviaanyhogͲrelatedtransportationmethods
overseas.FeedͲrelatedcontaminationseemstobeapossibilityfortheoriginofspread.Itwasreportedthattheinfectedfarm
didn’tuseanyporcineplasmainitsfeedingredients.PersonͲrelatedfomitessuchasbootsorclothingcouldbeapossiblerouteof
transmissionStateofficialsarepreventinganymovementofpigstootherislandsofHawaiifromOahuinhopesofpreventing
furtherspreadofvirus.
UkrainehasalsorecentlyexperiencedseverePEDinmultipleherdsaccordingtoDr.JohnCarr.Hedescribedthediseaseassevere,
similartotheChineseorAmericanexperienceratherthanthemilder,earlierͲdiscoveredEuropeanoutbreaks.Carrdescribesthe
farmers’responsetoinfectionintheUkrainealongthelinesofaslipperyslope.Hereportsthatproducersmayletpigsfinish longer
whichmaybedetrimentaltopigflowandbiosecurityalike.Thismaycreateconditionsforlateraltransmissionofthevirustoother
farms.Dr.Carrspecificallyidentifiedfalteringtruckdisinfectionasapossibleculpritoftransmission.Transportationhasbeen
identifiedasalikelyrouteoftransmissioninmarketpigandcarcasshaulingvehiclesinUnitedStates.Dr.Carrexpectedthis virusto
spreadtootherfarmsnotonlyintheUkraine,butacrossborderswithinEurope.
Thesereportsarediscouraging.OurnumbersinthemonitoredherdswithinourSwineHealthMonitoringProjectshowthatinthe
first1.5yearsofmonitoringintheUS,approximately55%oftheherdswereinfected.Sofarthiswinterwehaveseensporadic
outbreakswithonly7herdsbeingreportedasreͲinfectedsincethebeginningofJuly.Partofthisreductioninincidencemaybedue
toimmunityintheUSsowpopulation.Ifthatisthecase,onewouldexpectlowincidenceofspreadwithinEuropeduetopreͲ
existingherdimmunitycausedbyPEDvstrainsthatapparentlyareoflowvirulence.Werecentlycompletedasowchallenge
experimentwherewereportedatleastpartialcrossprotectionbetweenalowvirulencestrainandthemoresevere,originalPEDv
strain(https://docs.google.com/a/umn.edu/file/d/0BzGsnfsQ28heNmJCbXZhRm9XYjQ/edit).
HawaiiarticlebyTomPolansek(Reuters),“DeadlypigvirusjumpstoHawaii,animalfeedtested”12/1/2014
http://www.reuters.com/article/2014/12/01/pigͲvirusͲhawaiiͲidUSL2N0TL1UA20141201
UkrainereportbyHarrySiemens“AnoutbreakofPEDvintheUkrainecouldbethestartofmajoroutbreakinEurope”11/26/2014
http://www.siemenssays.com/2014/11/26/outbreakͲpedvͲukraineͲstartͲmajorͲoutbreakͲeurope/
12/12/2014