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PRACTICAL ASPECTS OF LSD CONTROL FILED EXPERIENCE & DILEMMAS
Dr Nadav Galon and Dr Eeva S.M. Tuppurainen
CATTLE POPULATION (2012)
Farm size Heads (~) Herds Type
40-1,100 250,000 828 Dairy Farms
50-6,000 200,000 457 Feedlots
20- 1,000 60,000 596 Pasture
500,000 2,000 Total ~
3
DAIRY - ZERO GRAZING BEEF -ZERO HOUSING
Density maps- E. Klement
LSD IN ISRAEL OUTBREAK TIMELINE
Estimated introduction
26/07/2012 ?/06/2012
Vaccination Pox-1
1st dairy case 1st Dx
by VS- KVI Vaccination
Non-mandatory
Mandatory Vaccination Neethling
Pox-10
03/2013
24/10/2012
28/07/2012 06/2016
Last case
08/2013
1989 2006 2007
PREVIOUS LSD OUTBREAKS IN ISRAEL
6
1989 2006 2007
2012 1989- total Stamping Out (SO) 2006/2007- Partial SO 2012- minimal SO
28 -07-2012
Lebanon
Israel
Syria
7
2
19
Initial picture
28.07.2012
~ 40 Beef herds
4,000 cows
Mutual grazing
Poor pasture
Mountains, forests
Over crowding
10-60% morbidity
10
LEBANON
SYRIA
EARLY DETECTION
In continent, in country, in region
Preparedness; knowledge, awareness
Remote border areas
Few farmers, part time farmers, intensive/ extensive
Few official inspectors, few clinicians, no mandatory visits
Cattle gathering abilities; paddocks, cattle chutes, workers
Sampling , shipment; incorrect – false negative
Israel; Window gap- infection to detection ~ 6-8 weeks (skin scars support estimation)
MONITORING & SURVEILLANCE
Knowledge & training (“exotic/ tropical… diseases”- terms of the past!)
The 3 R’s: Routine, Records, Reports
Same principles; adapted to specific task & conditions
Multi-disease approach
Resources; prevention cheaper than control
Mandatory visits to each herd; useful yet leaves large time gaps
Non official players – other interests
Advanced technology; IR, Pedometry, GPS…? Dairy vs beef
DIAGNOSIS IN THE FIELD
Awareness & knowledge
difficult first ; new country, new region, not learnt
easy- once you have seen it
Mild… moderate cases can be missed, ignored- intentionally/ non intentionally
Twilight zone – edge of outbreak region - vaccination of incubating cattle
Lab submission
Important in early, new herds/regions, unclear cases, monitoring outbreak boundaries
Avoid lab swamping
Important post outbreak; suspicions, passive/ active surveillance
GSP - Good Sampling Practice – especially filed personnel
VACCINE & VACCINATION
The homologues vaccines (OBP) and JOVAC 10X Sheep Pox – protect
All available vaccines are non-GMP
Purity- Contaminants
Potency - alters
Field safety trial 2013 - no adverse reaction
“Neethling response” < 1%
Handling, application; many causes for failure
Coverage; partial / insufficiency- outbreaks
Incentive / cost-benefit to farmer/ private vet
50% of infected animals sub-clinical - multiuse needle – excellent transmission
Incubating herds/ less than 3 weeks prior to incursion
Regional & Preemptive vaccination approach
Cost-Benefit analysis
STAMPING OUT- PRO’S
Total stamping-out can be effective and practical when;
the first incursion to a country or a defined region is detected and notified early enough
the infection to detection period is short
the threat of repeated incursions is low
Epi’ unit can be well defined and isolated
When it works;
quick & effective
Regaining freedom of LSD
back to normal business
ISRAEL LSD CONTROL POLICY: 1989- total Stamping-Out 2006/2007- Partial SO 2012- limited SO
STAMPING OUT- CON’S
Different countries – different scenarios
Expensive ( 500- 2,500 Euro / cow vs 2-3 Euro/cow - vaccination)
Indirect losses
Very expensive when ineffective … when to give up ?
Demands much more personnel, time and resources than vaccination
Destructive to farmers livelihood, economy and sustainability
public perception and media / political interference
“No one solution fits all” – adapt policy to reality
EFSA statement 2016 – “if vaccination coverage is high enough- S.O. has minor effect”
CARCASS DISPOSAL
Legislation & Environmental factors; water, land…
Amount of carcasses to dispose
Availability on farm/ near farm, equipment, cost
Is a carcass an important source of LSD spread?
Cover, repellent spray
Distance to incineration plant/ rendering plant (Israel -1)
Vehicles route- entering non-infected farms
Special vehicles/ special routes - extra costs
Mobile incineration plant
FARM BIOSECURITY
Most infections caused and spread by F.B.I= Flying Biting Insects
Definition of farm boundaries; grazing, non-grazing
Difficulties
Herd size- Backyard herds; 1-10 heads
Herd density
Free roaming, nomadic
Communal grazing
General disinfection mostly ineffective
PPE- reduce inter-herd transmission
Post outbreak cleansing and disinfection? Cost-Benefit Analysis
SPREAD OF LSD
Slow & sure (compared to BT, BEF, EHD)
Efficient; all herds, all cattle
Mostly by F.B.I
Non specific
FBI move with cattle
Move without cattle – 1-2 km
Infected cattle move- meeting FBI on the way, at new site – sales, abattoirs…
Milk tankers, carcass disposal, hides, meat ?? – no practical proof ~ negligible
Halt farm commercial activities; Difficult to impossible ; sales, Vet, AI, suppliers
No wildlife involvement
Musca Stomoxys Haematobia
NB Players in Israel
VECTOR CONTROL
Various vectors; different breeding sites, season, housing…
Repellents vs insecticides
Registration; on animals, environment, effect on other fauna
May reduces intra-herd spread
Hardly effects inter-herd and inter-region spread
Short effect. Reduced by rain, summer cooling by water (3-6X day)
Mild winter (Mediterranean) – FBI active in winter
Colder winter; over-wintering and burst in spring
Research; valuable , limited contribution to control
Cost- Benefit ?
Where there is cattle - there are FBI
Horn flies
CATTLE MOVEMENTS CONTROL
legislation, regulation, “green Police”
Permit prior to movement
Inspection, enforcement – limited recourses
Remote areas, roads accessibility
Holidays effect; Eid Al Adha, Ramadan… (FMD as well)
Longer period/ stricter measures - reduce compliance
Private vet “clinical freedom certificate”- problematic
In long and wide epidemic- long distance spread will occur
RISK PERCEPTION & ANIMAL WELFARE
Farmers: commercial vs traditional
Politicians & legislators response to farmers, media… regulators
“why destroy healthy cattle” / can recover/ recovered ?
Recovery price; economical, social, quitters
Euthanasia
Salvage, severe cases – acceptable
Techniques; legal, available means, sedation
Tolerance; farmer, media, vets/ inspectors, animal activists
WHEN THE OUTBREAK ENDS
LSD has a sweeping mode
Exposed Population protected ; by infection / by vaccination (after 3 weeks)
Repopulation; a.s.a.p (vaccinated herds- no empty farms)
Replacement rate:
Dairy – 20-30% annually
Beef dams- 10-20% annually
Feedlot- months
Vaccinate for several (?) years
Minimize trade disruptions – increase restrictions - increase non-compliance
Active surveillance- expensive and complex
SIGNIFICANCE TO OTHER TAD’S
“Out of Africa”/ Asia…
Through the Middle East
Other cross-Mediterranean routes
“ASF route”
Vertical (BTV 8)
Stop it at the earliest convenient point
Reservoir behind the border
“the facts of today are the fallacies of tomorrow” EFSA Journal 2015; 13(1):3986
Live bovine movements 2008-2014
EPILOGUE
Professionalism; Theory - knowledge , Practice- the small details
Solidarity; communication- collaboration- sharing
Transparency and risk communication with all relevant stake holders
Flexible strategy and adjustments of tactics during the outbreak
“It’s tough at the top” – applause to decision makers and executors at all levels & tasks