Within the frame of the Swiss Animal Health Strategy 2010+ (www.bvet.admin.ch), the Swiss Federal Veterinary Office initiated a project in order to evaluate a vaccination-to-live strategy against Foot and Mouth Disease (FMD). Within the scope of this project, the benefit of emergency vaccination within 3 km (V3) and 10 km (V10) around an infected premises (IP) was evaluated and the technical feasibility of such an emergency vaccination was analyzed regarding the corresponding EU FMD directive (COUNCIL DIRECTIVE 2003/85/EC). We used the Davis Animal Disease Simulation (DADS) model (Carpenter et al., 2011; Durr et al., 2012) in order to compare the conventional disease control strategy with and without an additional emergency vaccination strategy (V3 and V10, respectively). In a second step, we analyzed the implementation of a vaccination-to-live strategy with regard to its feasibility and economical consequences. It was shown that emergency vaccination in a low-livestock density country like Switzerland would be only beneficial in a situation where the epidemic is already widely distributed (V10 strategy). On the other hand, our feasibility study with respect to the vaccination-to-live strategy revealed that the animal movement restrictions within the vaccination zone would lead to a significant increase in welfare culling especially in the pig production sector due to the long duration of the restrictions. The expected increase in welfare culling due to the long duration of animal movement restrictions within the vaccination zone actually impedes the implementation of a vaccination-to-live strategy for ethical and economic reasons. Therefore, the implementation of animal movement restrictions during the different phases of a vaccination-to-live process has to be re-examined and adjusted accordingly. (c) D. C. Hadorn / EuFMD (eufmd@fao.org)

1. Federal Department of Economic Affairs FDEA
Federal veterinary office FVO
Evaluation of the benefit
and feasibility of a
vaccination-to-live strategy
in FMD free countries
D.C. Hadorn1, S. Dürr2, B. Thür3, L. Perler1, T. Jemmi1
1 Swiss Federal Veterinary Office, 2 Veterinary Public Health Institute,
3 Institute of Virology and Immunoprophylaxis
EuFMD Open Session 2012

2. Evaluation of FMD emergency
vaccination in Switzerland
Basic questions to be answered to adjust contingency
planning:
a) Target species for emergency vaccination (cattle – small
ruminants – pigs)
b) Dimension of vaccination zone (3 km = V3 or 10 km = V10)
c) Time frame for emergency vaccination (immediately after
detection of first case or later)
d) Feasibility of a „vaccination-to-live“ strategy (Council
Directive 2003/85/EC)
…in order to achieve a benefit compared to conventional
disease control only
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3. Materials and Methods
• Simulation of FMD spread (serotype O „middle east“) within and
between herds (local area spread, direct and indirect contacts) with
Davis Animal Disease Simulation model1
General input parameters Value1
Initial diagnosis delay (diagnosis delay for index case) 10 days
Second diagnosis delay (diagnosis delay for secondary cases) 4 days
Inputs for emergency vaccination Value1
Application delay for 3 km vaccination zone 3 days
Application delay for 10 km vaccination zone 6 days
Protection delay for vaccination 14 days
Vaccine efficacy on herd level 0.9
1Dürr et al. Evaluation of the benefit of emergency vaccination in a foot-and-mouth disease
free country with low livestock density. Submitted to PVM.
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Evaluation of benefit and feasibility of vaccination-to-live strategy | EuFMD Open Session Oct 2012
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4. Results
a) Target species for emergency vaccination
Cattle Small ruminants Pigs
b) Dimension of vaccination zone and
c) Time frame for emergency vaccination
• No benefit for emergency vaccination under Swiss situation*
if vaccination campaign is started right after detection of first
case (neither 3 km nor 10 km vaccination radius)
* Low animal density (<167 ruminants and pigs / km2)
• If the epidemic becomes extensive, vaccination with radius
of 10 km around IP may be beneficial in terms of reducing
the number of herds infected and the epidemic duration
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5. d) Feasibility of vaccination-to-live strategy
Goal of vaccination-to-live strategy:
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Evaluation of benefit and feasibility of vaccination-to-live strategy | EuFMD Open Session Oct 2012
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6. Restriction Measures in terms of animal movement Minimum duration
zone
Protection No animal movement between holdings within, in At least 15 days plus time for killing &&
At least 15 days plus time for killing
Zone and out of the protection zone disposal & preliminary cleansing and
disinfection
At least 30 days
Surveillance No animal movement out of surveillance zone; At least 30 days
Zone animal movement between holdings permitted
after clinical inspection
Vaccination zone At least 6 months in total
Phase 1 No animal movement between holdings within, in plus 30 days
Time for vaccination plus 30 days
and out of vaccination zone
Phase 2 No animal movement between holdings within, in Time for clinical and serological survey
and out of vaccination zone plus classification of herds
Phase 3 No animal movement out of vaccination zone; 6 months minus time for phase 1 and
animal movement between holdings is subject to phase 2
authorization; unvaccinated animals with
restrictions (testing)
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Evaluation of benefit and feasibility of vaccination-to-live strategy | EuFMD Open Session Oct 2012
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7. d) Feasibility of vaccination-to-live strategy
• Animal movement restriction within vaccination zone
(phase 1 and 2) is as severe as in protection zone but
more than twice as long
Significant increase in welfare culling, mainly in pig
production sector, expected
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8. Discussion
Under Swiss conditions and in terms of the actual legal basis,
the feasibility of a vaccination-to-live strategy is not given.
Points to be discussed:
• Adaptation of restriction measures if vaccination zone is
established outside protection/surveillance zone (different risk)
• Necessary duration of „stand-still“ within vaccination zone (only
during vaccine application phase?)
• Adaptation of restriction measures in holdings with and without
vaccinated animals (target species of vaccination program?)
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Evaluation of benefit and feasibility of vaccination-to-live strategy | EuFMD Open Session Oct 2012
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9. Thank you
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Evaluation of benefit and feasibility of vaccination-to-live strategy | EuFMD Open Session Oct 2012
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