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Draft Disease Control Policy Statement

Control Strategy

In agreement with a core group of industry stakeholders, the UK remains

committed to a disease control approach which aims to contain disease until

vaccination is an available disease control option, in line with ‘Phase 1’ of the

UK Bluetongue Control Strategy. This is taking into account:

· the epidemiological situation (i.e. cases of Bluetongue (BTV8) currently

remain contained to the East and South Eastern parts of England);

· the time of year (i.e. in advance of the 2008 vector season);

· cost benefit analysis of disease control measures and its likely

economic impacts; and

· the development (and order) of BTV 8 vaccine for England.

This assessment remains under constant review, and recognises that the

disease situation could change at any time (e.g. in advance of vaccine

becoming available to use). Further cases of Bluetongue a significant

distance from the existing Protection Zone may lead to a change in strategy.

Annex A sets out more detail on the rationale behind specific controls.

Winter 07/08

We are currently in the “seasonally vector free period” as set out in EU

legislation – a period during which midge activity, and therefore transmission

of disease, are greatly reduced, or stopped, and movement controls are

adjusted to allow some moves out of zones under specific pre-movement

testing conditions.

Historical data suggests such a period may run into March, but this is

dependent upon meteorological conditions and midge activity. More

information will be published shortly on the likely criteria and process for

declaring an end to this year’s vector free period.

The winter period provides a vital opportunity in which to review the disease

situation and the control strategy for 2008. Disease surveillance work is

therefore being undertaken to evaluate the full extent of disease spread in

2007, alongside data from reports of disease from farmers.

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n the meantime, this statement sets out the broad aims and intentions of the

control policy for the Spring and Summer of 2008.

Pre-Vaccination Policy (Winter – Spring)

A suitable inactivated vaccine for BTV8 has only very recently been

developed. Defra placed a firm order of 22.5 million doses (2.5 million of

which are reserved for potential use in Wales) from Intervet in December,

after a detailed competitive tender process designed to ensure best value,

that vaccine is currently being manufactured. This is a lengthy process which

is not expected to be fully completed before May 2008 at the earliest. Until

this vaccine is available, tight controls will be maintained to contain disease

within existing zones as much as is possible. In the meantime, we have been

developing a detailed plan as to how that vaccination will be delivered which

will shortly be published and submitted to the European Commission for

approval and consideration of funding.

Once the vector free period ends (and we enter the 2008 vector season),

movement controls will revert to the strictest default regime, with movement

out of zones permitted only in very limited circumstances. This will be

reviewed as the disease situation develops.

Vaccination Policy (Spring – Summer)

Once a vaccine bank has been delivered, livestock keepers will be given the

opportunity to purchase from this bank.

There are a number of constraints as far as the implementation of vaccine is

concerned:

· Intervet aim to start delivering vaccine in stages from May 2008,

although it will take time for the whole amount to be delivered;

· Based on experience on the continent, disease could begin reemerging

and circulating before then;

· Vaccination is only allowed under EU rules in the Protection Zone (PZ);

· The PZ would need to be extended to allow people currently outside

the PZ to vaccinate.

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n agreement with the core group, the vaccination plan and wider control

policy will therefore have the following aims:

· A simple mass vaccination programme, with farmers purchasing

vaccine and using it voluntarily;

· To prioritise the initial availability of vaccine to the existing PZ.

· To make vaccine available as widely as possible, and rapidly, after

those in the existing PZ have been given sufficient opportunity to

purchase, and as vaccine is delivered by Intervet.

· To expand the PZ as soon as possible to facilitate vaccine availability

(to the extent of the SZ boundary as soon as vaccine delivery allows,

possibly staged with some further prioritisation on a risk basis if

vaccine is not delivered quickly enough).

· To expand the PZ to the whole of England as soon as sufficient

vaccine is available to allow opportunity to vaccinate across this area.

· To implement an industry-led campaign to promote the benefits of

vaccination and encourage pre-ordering, to increase uptake.

To achieve the above aims, assessment of the location of zone boundaries

will be carried out throughout the period with the core group, taking into

account vaccine uptake and availability; disease situation and movement

risks; economic impact etc.

Annex A

Current disease control strategy - rationale

The current strategy is being delivered using disease control measures such

as controlling the movements of susceptible animals, as set out in EU

legislation. The rationale for this approach is set out below:

Vectors

o Bluetongue is spread between animals by a midge vector (Culicoides

spp.). Infected midges have the potential to spread disease in a local

area (up to 1.5-2km a day in some cases)

o It is neither possible nor proportionate to attempt to eradicate or control

populations to an extent that would mitigate against or have a desired

controlling effect on the spread of Bluetongue.

Susceptible animals

o Susceptible animals (i.e. all ruminants and camelids) potentially are a

‘reservoir’ for disease for up to 60 days when infected. Movements of

infected animals has the potential to spread disease a much further

distance than midges.

o It is extremely difficult/impractical to completely protect an infected

animal from attack by midges. Therefore an infected animal provides a

source of virus for a local midge population wherever it is located (and

potentially further disease transmission in that local area)

o While it is not possible to stop the local spread of disease through

movement of midges. It is possible to control the spread of disease

through the control of movements of infected and potentially infected

animals.

Disease control measures

Protection Zone

o A Protection zone is established in order to try to contain disease within

an area around an infected premises. The Protection zone boundary

should always be at least 20km away from any infected premises.

o Movements of animals and midges may still spread disease within the

zone, however, sufficient surveillance and reporting of signs of disease

should monitor the levels of spread, and new infected premises are

most likely to be found within this zone.

o Even so, given the nature of the disease, it can be assumed that there

will always be a level of undetected infection in the Protection Zone i.e.

as clinical signs of disease are not always apparent.

o Therefore, any movement of susceptible animals out of the Protection

zone has the potential to spread disease to a new and previously

uninfected part of the country.

o Animals can move freely within a PZ, so any decision to extend a PZ

geographically (e.g. to allow vaccination in a wider area) must be

balanced against the risk of wider movement of potentially infected

animals.

Surveillance Zone

o A Surveillance zone is established in order to maintain a buffer area

around the Protection zone. This size of the zone is set in EU

legislation at at least 150km radius from any infected premises.

o Due to the nature of the spread of Bluetongue, new cases can be

found outside of the Protection Zone.

o Any movement of susceptible animals out of the Surveillance zone

(although a lesser risk than the Protection zone) has the potential to

spread disease to a new and previously uninfected part of the country.

o Therefore the zone, and the movement restrictions within provide a

vital buffer against further, and wider spread of disease.

Moves to Slaughter

o Given the nature of the UK farming industry, there is an economic need

to allow moves to slaughter, potentially long distances and moving out

of zones.

o As infected animals (showing no symptoms) can potentially move to

slaughter out of the restricted zones, there is potential for midges at the

abattoir of destination to bite them and become infected. This can

potentially lead to the creation of a local infection in a previously

uninfected area.

o Therefore there is a need to mitigate against the risk of midges biting

potentially infectious animals in abattoirs, through licence conditions.

As such the following measures are required for moves to slaughter

(outside the “vector free period”, VFP).

o A requirement for animals to arrive at abattoirs after dawn, and

slaughter animals of the before dusk each day. This minimises

the risk of potentially infectious animals being bitten at abattoirs

during peak times of midge activity i.e. dawn and dusk.

o Similarly, potentially infectious animals should not be present in

abattoirs overnight, as midges are still fairly active at night, and

would be particularly attracted by lighting at the abattoirs (as

opposed to during the day)

o Vehicles used to transport animals should be treated with

authorised insecticides prior to the movement. This will reduce

the likelihood of potentially infected midges entering the vehicles

and moving with the animals out of the zones.

o Insecticide treatment of the animals to mitigate the same risk is

not possible due to the withdrawal periods.

o During the period of low vector activity is has been possible to relax

these time constraints and allow movements of livestock to slaughter

from the restricted areas through dedicated slaughter markets.

Moves to Live

o Due to the nature of the disease, all animals in the Protection and

Surveillance Zones must be considered as potentially infected

(although there is a higher risk in the PZ).

o Therefore, any moves of animals outside of the Restricted Zones can

potentially lead to the creation of a local infection in a previously

uninfected area.

o In the current period of low vector activity moves to live are being

allowed out of the current Restricted Zone, providing the livestock

meets specific criteria and has a pre-movement test, but such moves

will only be allowed after the VFP ends under very specific criteria (e.g.

naturally immune animals). Moves out of zones to slaughter will

however be allowed (see above).

Transiting zones

o All movements of animals from and to a lower risk area through a

higher risk area provide a level of risk to the transiting animals of being

bitten by potentially infected midges while in transit, and transferring

infection to a previously uninfected area.

o Therefore conditions are required for such moves (outside the VFP) to

mitigate against the risk of animals being bitten in transit.

o Moves from free area to free area through a SZ, are subject to

the vehicle and animals being treated with insecticides prior to

entering the SZ. No stops, apart from required rest periods or

for welfare reasons are permitted.