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					     Foot and Mouth Disease
       Outbreak in Britain
               Nigel B. Cook MRCVS
            University of Wisconsin-Madison



July 2001                                     1
    Wisconsin Biosecurity Workgroup
 The information in this presentation was developed
  through a coordinated project of University of
  Wisconsin-Extension, Cooperative Extension;
  Department of Agriculture, Trade and Consumer
  Protection, Division of Animal Health; University of
  Wisconsin-Madison – College of Agricultural and Life
  Sciences and School of Veterinary Medicine; and
  U.S. Department of Agriculture, APHIS, Veterinary
  Services.




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             What Causes FMD
             ?
Cooking at 72oC
and extremes of
pH kill the virus         A Picornavirus –
                       highly resistant in the
                        environment – lasts
                              months

7 serotypes AOC,
SAT1-3, Asia1
60+ subtypes

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              February 1, 2001
               Slaughterhouse
            Brentwood, Essex, UK
27 pigs found with
  vesicular lesions
First major FMD
  outbreak in UK
  since 1967



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Signs
Pigs show
obvious signs of
lameness and
excrete lots of
virus




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  Incubation
               Incubation is rapid
               at 2-8 days and
               morbidity is near
               100%
               Cows show very
               obvious signs
                Salivation
                Lameness
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            Spread
               • Vesicles contain
                 large numbers of
                 virus particles

               • Spread via saliva
                 and aerosol
                 starting 24-96
                 hours before
                 clinical signs
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     This is not a mild disease which cows
         and pigs recover from easily!




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Signs




            Signs can be subtle initially.
            Infection persists in cattle
            (not pigs) in the pharynx
            (20% > one year)
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Signs




            Sheep show very few noticeable
                   signs of disease
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 Infection rapidly
entered the sheep
    population       Source of
                       the
                     outbreak




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Spread
            Massive
            movement of
            sheep across the
            country for 2-3
            weeks before
            clinical signs were
            recognized.
            Windborne spread
            probably not of
            major significance.
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Spread


How did the virus enter the country
and infect a pig ?




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Spread
• Pan-Asian Type O strain occurred in S.Africa,
  Baltic region, S.America, Greece, Russia, Japan,
  Korea and Mongolia in 2000.
• Virus survives in uncooked meat.
     • Imported meat used in Chinese restaurants
     • Army catering waste
     • Illegally shipped meat through airports
     • Bio-terrorism ?
• Waste meat fed to a pig, containing live virus
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Spread

France       2
Netherlands 26
Ireland      1




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            Options for control




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Control        Slaughter
              animals on
             affected farm
            within 24 hours




             Slaughter animals
               on neighboring
              farms and all in-
             contacts within 48
                   hours
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Control
            Slaughter affected
                 animals




              Vaccinate a ring
             of animals around
                the outbreak

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Vaccination
•Only sub-type specific
•Ends all trade in meat and livestock across borders
•Does not stop excretion in already infected animals
•Vaccinated animals will need to be slaughtered at
      the end of the outbreak to open trade routes
•How do you go about vaccinating large numbers of
     farms without transferring infection?
•What if the virus jumps the vaccination ring?


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The UK control policy

•Banned movement of all livestock in the UK
•Any suspect infected animal reported to MAFF
•Form A prohibits movement of any animal,
person or thing on or off the suspect farm
•If the VO confirms the suspicion a Form C is
imposed, prohibiting the movement of animals
within 8km radius and send samples for testing
(95% affected farms slaughtered based on only
clinical signs)
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The UK control policy
•If positive is confirmed an Infected Area is
imposed 10km around farm. Movement of people
on affected farm controlled by police, disinfect
premises and people, slaughter all animals on
affected farms, destroy feedstuffs
•All dangerous contacts destroyed – neighboring
farms, in contacts via markets and dealers (in
Cumbria all sheep and pigs within a 3km radius)


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The UK control policy
•Milk is collected from
all farms except
       those under
Form A
•Appropriate clothing,
disinfection, filters
and pasteurization
enforced

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            Options for disposal

     •Burn ( risk of spread from fire < 1 in a
     million)
     •Bury ( if born after August 1996)
     •Render




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            The harsh reality of a
              slaughter policy




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Funeral pyres




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Burial
chambers




 July 2001   30
 Will the U.S. get FMD ?


            ?
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    Wisconsin Biosecurity Workgroup

      University of Wisconsin-Extension
      University of Wisconsin-Madison
             CALS/Veterinary Medicine
      University of Wisconsin-River Falls
             Department of Agriculture, Trade and
                    Consumer Protection
      U.S. Department of Agriculture, APHIS,
      Veterinary Services.



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