The German BVD Control Program: Principles, Progress, Problems and Economic Considerations Klaus Doll Clinic for Ruminants, Faculty of Veterinary Medicine, Justus-Liebig-University Giessen, Germany
BVDVeradicationstrategyin Germany Principles 1. Legal basics: Official Federal BVD regulation(bvd-verordnung), in forcesincejanuary1, 2011 2. Aim: Reduction of PI-prevalence Establishing of unsuspicious(virus free) animals and farms(certified) Finally freedom of BVDV of the German cattle population (within 3 4 years)
BVDVeradicationstrategyin Germany Principles Antibody status (individual animals, herd) remains unconsidered. Controltarget: PI animal Transient infections not considered, since it was assumed that they do not play a significant role in the spread of BVDV infections.
BVDVeradicationstrategyin Germany Principles 3. Way: Obligatoryinvestigationof all calves up to 6 th monthof life for BVDV antigen / genome Elimination of pi-animals(immediately) Only trade with certified unsuspicious animals Prevention of reinfections by qualified measures and vaccination(voluntarily)
BVDV Eradication in Europe Vaccination prohibited Vaccination allowed
Cattle imported to Germany in 2010 from Countries without mandatory BVDV Control EU guideline 64/432: Free trade of cattle with unknown BVDV status not restricted
Calves tradein the EU 2012: The Top 5 Calves < 80 kg live weight BVDV type 2 -Doll & Holsteg
BVDV EradicationStrategyin Germany Key point: Testingof all newborncalves (< 6 monthof age) for BVDV antigene/genome Major test matrix: ear notches Major testmethods: real time RP-PCR ande RNS ELISA in equalparts In contrast to the Scandinavian model: initially no serological tests
BVDV EradicationStrategyin Germany Meanwhile, all calves are tested until 7 th day of life, because: - Regulation (EC) 1760/2000: Calves have to be ear tagged until 7 th days after birth. Advantages of ear notch samples: - Uniqueassignment of the sample / animal - No diagnostic gap - Pooling of samples (real time RT-PCR)
BVDV EradicationStrategyin Germany Collection and dispatch of samples by the farmers Round ear button for2 nd test or older animals
BVDV EradicationStrategyin Germany BVDV-unsuspicious animal: livelong status
BVDV EradicationStrategyin Germany Persistent viraemic(pi) animal: Animal tested 2x positive for BVDV with an officially approved method (interval: 21 60 days) Animal without2 nd checkup Animal with Mucosal Disease -Case Definition - Descendant of a persistent infected mother ("derivative status ) Only cattle once tested negative - i.e. BVDV unsuspicious - are allowed to leave the farm (exceptions: slaughter, export)
CompensationsforCullingof PI-Calves Land Amont per PI-Calf Special Conditions Baden- Wurttemberg Max. 120 Bavaria 105-230 (depending on breed, sex) If calf is killed within 14 days after 1 st positive testresult If calf is killed until 21 st day of life Brandenburg 100 If calf is euthaniziduntil 28 th day after pos. test by a vet. Hessen 90 If calf is killed within 14 days after 1 st positive testresult LowerSaxony 190 If calf is euthanized until 28 th day of life by a vet. Rhineland Palatinate 50 (+30 foreuthan., vet. ) If calf is killed within 14 days after 1 st positive testresult
Progress of the German BVD Eradication Number of PI animals 17,410 Proportion of PI in the cattle population 0.14% Proportion of PI in the calves born in 2011 0.36% Number of farms with PI animals 6,016 Proportion of farms with PI animals 4,1% Schirrmeier & Strebelow(2012)
Characterization of 445 German BVD Isolates (5 ntr-phylogeny) 76.2% of all isolates belongto BVDV-1b or1d 2.2% BVDV-1a 5.1% BVDV-2 Schirrmeier, Strebelow Beer (2012)
BVD Controlin Germany Numberof PI animals Period from January 2011 to July 2013 Number of PI animals 7000 6661 6303 6338 6000 5000 4869 4000 3000 3575 3037 2959 2614 2000 2066 1668 1000 0 Q1 2011 Total number of PI animals since Jan. 2011: 40,090 Q2 2011 Q3 2011 Q4 2011 Q1 2012 Q2 2012 Q3 2012 Q4 2012 Q1 2013 Q2 2013 Q3 2013
Cumulative PI-Prevalence in German Laender (Percentages relating to the number of birth) Germany: 2011: 0.50% 2012: 0.24%
BVD controlin Germany Further Development of PI Numbers Number of PI animals 7000 6000 6661 6303 6338 5000 4869 Trendline (linear) 4000 3000 2000 3575 30372959 2614 2066 1668 1000 0
BVD controlin Germany Further Development of PI Numbers Number of PI animals 7000 6000 6661 6303 6338 5000 4869 Trendline (exponential) 4000 3000 2000 3575 30372959 2614 2066 1668 1000 0
BVDV PI-Calves in formerly negative Herds Seeger et al. (2013): BVD control in Baden-Württemberg Number of herds, in which the respective first PI-calf was born Start of the eradication program End ofthe 1 st year Herds with new PI-calves BVD-neg. in the1 st year Nearly two years after the start of the compulsory BVD eradication programme first successes become evident in Baden-Württemberg. The number of calves persistently infected with BVD-virus has decreased by more then the half. However BVDV still occurs in formerly negative cattle herds.
BVDV Eradication: Consequences and Problems Drasticdeclinein the numberof PI animals(but not to zero) Increase in the number of seronegative animals and herds Reduction in the number of vaccinations (farmers and veterinarians perceive BVD no longer as a threat) Animals with missed during 1st testing (false negative results) Insufficient biosecurity measures Severe BVD outbreaks caused by highly virulent BVD strains (Importance of transient infections should not be underestimated) Pestivirus infections of other ruminants, atypical BVD strains?
BVDV Eradication: Consequences and Problems Prevention of Introduction of BVD Virus in Noninfected Herds Biosecurity measures as a central part! Compliance of the farmers (and veterinarians)
BVDV Eradication: Consequences and Problems Onlycattleabsolutelyfreeof BVDV is allowed to leavethe farm Onlycattleabsolutelyfreeof BVDV is allowed to enterthe farm Pregnant (Trojan) cows! Stringent hygiene measures (isolation facilities, contact to other livestock, animal traders, veterinarians, etc. ) BVDV type 2 -Doll & Holsteg
Biosecurity Measures- Reality
Dairy herd with 1.100 cows in Saxony, BVDV-unsuspicious: Vaccinate against BVDV or not? Introduction of virulent BVDV into a naive diary herd ends in a disaster German veterinary authorities recommend vaccinations, based on experiences with recent BVD outbreaks
Consequences Freedom of BVDV on a national levelwithin 4 years?? The duration (and costs) of such eradication programs are usually underestimated Surveilanceprogram after becoming BVDV-free (Serology?)
EstimatedCostsof BVD Eradication in Germany (Total 12.3 Mio. cattle, 4.9 Miocows) Year 2011 2012 Tests: Numbers / Costs PI animals: Number/ Compensations 6.0 Mio. 42.0Mio. 4.6 Mio. 32 Mio. 24.171 2.5 Mio 12.1285 1.2 Mio. Total Costsper Year 44.5 Mio 33.2 Mio Switzerland: Estimated costs of BVD eradication: 55 Mio. CHF (45 Mio. ) Convertedto German animal numbers-> 360 Mio.
Fundingof BVD Eradication in Germany Government - Logistics, laboratory analyzers, personnel costs Tierseuchenkasse(Animal Diseases Fund; financed by contibutions of all farm animal owners plus Government subsidies) - Test costs, material, compensations, (vaccinations) Farmers - Additional tests, working time, vaccinations
BVD Eradication EconomicAspects Eradication of BVDV infections only costeffective, if it can be completed within a few years (Schaller et al., 1997; Valle et al., 2005). Eradication of BVDV is very easy: All you need is enough money and motified farmers (S. Alenius) BVDV type 2 -Doll & Holsteg
In Danger and Deep Distress, The Middleway Spells Certain Death (In Gefahr und größter Not bringt der Mittelweg den Tod) Alexander Kluge