Walrond Overview Organism Economic Impact Epidemiology Transmission Prevention Actions to Take Species Affected Domestic pigs Feral swine Wild pigs Eurasian wild boars Warthogs reservoir ID: 908335
Download Presentation The PPT/PDF document "African Swine Fever" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
African Swine Fever
Dwight Walrond
Slide2Overview
OrganismEconomic ImpactEpidemiologyTransmissionPreventionActions to Take
Slide3Species Affected
Domestic pigsFeral swineWild pigsEurasian wild boarsWarthogs (reservoir)Bush pigs (reservoir)Giant forest hogs
Slide4The Organism
Slide5African Swine Fever Virus
Asfarviridae: AsfivirusLarge, envelopedDNA virusOnly arbo-DNA virusMore than 20 genotypesVary in virulenceHigh virulence: up to 100% mortalityLow virulence: seroconversionInfects monocytes and macrophages
Slide6African Swine Fever Virus
Highly resistant in environment, especially at lower temperaturesSurvivalSeveral days in fecesMonth(s) in contaminated pensUp to 18 months in bloodOver 140 days in some pork productsSalted dried hamsYears in frozen carcasses
Slide7Virus Inactivation
Most disinfectants ineffectiveDisinfectants on nonporous surfacesSodium hypochlorite, citric acid, some iodine and quaternary ammonium solutionsMeat/tissue productsHigh temp (70oC/150oF) for 30 minCan be inactivated pH below 3.9 or above 11.5Higher pH needed if serum present
Slide8History and Importance
Slide9History
1921: Discovered in Kenya Today: endemic in most of sub-Saharan Africa including the island of Madagascar
Slide10History
1957: First occurrence outside Africa - Portugal1960s: Portugal and Spain1970-1980s: Spread to Europe The Netherlands, Italy, France, Belgium1990s: Disease eradicated
Remains endemic on the Island of Sardinia
Slide11History: Tick Vector
1963: Virus isolated from soft tick Ornithodoros erraticus1971: Western HemisphereCuba, the Dominican Republic, Haiti, BrazilEradicated
Slide12History
2007: Republic of GeorgiaSpread in CaucasusRegion (Eurasia),including RussiaFederation2015: Eastern EuropeLithuania, Latvia,Poland, RomaniaWild boar in Iran
Slide132018 Outbreaks
China: First time reported, domestic pigsBelgium: Wild boarsHungary, Estonia, Latvia, Lithuania, Russia, Poland, Ukraine, Bulgaria, Romania
Slide14History: Virus Introduction for Outbreaks
Uncooked/undercooked pork products fed to pigs (imported, illegal)Portugal , Spain (1960); Italy (1983); Belgium (1985); Russia (2008); Romania, China (2018)Raw pork waste/garbage at airport or shipping portsLisbon (1957), Malta, Sardinia (1978), Georgia (2007)Movement of infected wild boarsRussia (2008)
Slide15Economic Impact
Animal healthHigh morbidity and mortalityHighly contagiousImport and export bansMovement restrictionsQuarantine and depopulation Required for eradication1971-Cuba: 400,000 pigs2018-Romania: over 120,000 pigs2019- China : excess of 5,000,000Can become prolonged epidemic
Slide16Epidemiology
Slide17Geographic Distribution
EndemicSub-Saharan Africa Island of Sardinia (feral swine)Continued outbreaksCentral and Eastern EuropePoland, Czech Republic, Hungary, Romania, UkraineEurasia: Russia, CaucasusBelgiumNever been reported in United States, Canada, Mexico, Australia, New Zealand
Slide18Morbidity and Mortality
Morbidity up to 100%Previously unexposed herdsMortality varies with genotype virulenceRanges from 5% to 100%All ages affectedSubacute mortality = 30% to 70%May be asymptomatic in wild pigs
Slide19Transmission
Slide20Transmission
Direct contact with infected pigUsually oronasalAll secretions/excretions, blood, tissuesEnvironmental contamination with productsIngestion of contaminated pork products Fed to pigs – swill, waste, garbageCarcasses
Slide21Transmission
FomitesClothing, vehicles, equipmentEnvironmental contaminationBlood, diarrhea, fecesVectorsBiological: Bite from soft ticks OrnithodorosMechanical: Other insectsMosquitoes, biting flies (Stomoxys)
Slide22Humans are not susceptible to African Swine Fever
There is no public health or food safety concern.
Slide23Treatment
No treatment availableNo treatment should be attemptedNo vaccine availableResponse should be directed by animal health authoritiesDepopulationRestrictions on pig movements
Slide24Prevention
Slide25Prevention
Prevent direct transmission between infected and susceptible swineIsolate ill pigsPrevent contact with feral or wild hogs; when possible house pigs indoorsKeep newly acquired pigs separate from the herd for at least 30 days to assure health
Slide26Prevention
Prevent indirect transmissionDo not feed uncooked pork products to pigsSwill, garbage, wasteDisinfectionVehicles, equipment, footwear, clothingAppropriate disposal of manure and carcassesAvoid hunting wild hogs prior to contact with domestic pigsPrevent vector transmissionControl tick and other insect vectorsMay be difficult in endemic areas
Slide27Actions To Be Taken
Stamping out approachDepopulationSurveillance and investigationQuarantine and movement controlWildlife management and control