FMD: Alternatives to Scorched Earth Policy

Transcription

1 FMD: Alternatives to Scorched Earth Policy Albert Paszek, Ph.D. Cargill, Inc. 57 th Reciprocal Meat Conference University of Kentucky Lexington, Kentucky June 23, 2004

2 Foot-and-Mouth Disease (FMD) extremely contagious viral disease fever, vesicular lesions subsequent erosions of the epithelium of the mouth, tongue, nares, muzzle, feet, teats

3 Foot-and-Mouth Disease (FMD) Incubation: 1-5 days Duration: 1-3 weeks Morbidity: Extremely high ( 100%) Mortality: Low in adults (1-5%) In young animals: Very high (up to 90+%) Carriers: cattle, pigs, humans? Water buffalo, pigs - shedders Zoonotic significance: None

4 THREAT TO ANIMAL PROTEIN/ FOOD INDUSTRY

5 Natural incidence OR possibly...

6 ...Bio-/Agro-/Food-terror

7 Could mean the 9/11 for Livestock and Meat Industry

8 FMD Transmission Aerosols Direct contact Meat products Except deboned, aged beef (ph <5.7) Humans

9 FMD Epidemic Control QUARANTINE: disruption of food supply and trade KILL AND BURN: many healthy animals destroyed in UK - ~ 4 mln livestock slaughtered within a year (80% sheep) cost in US >$13B for single outbreak national US outbreak cost >$100B RING VACCINATE and hope we have the right vaccine for the strain causing the outbreak

10 Vaccination is a partial solution to FMD control Does US have an effective response to a nationwide FMD epidemic? Too many strains of FMD Not enough veterinarians to administer vaccine nationwide Vaccine produces same antibodies as FMD, therefore vaccinated animal and its products are not exportable

11 FMD Virus Serotypes Picornavirus (FMDV Poliovirus) 7 Types (with > 60 Subtypes) A (A5, A24, etc) O (O1, etc) C (C3, etc) SAT-1 SAT-2 SAT-3 Asia-1 (Courtesy of Dr. Alfonso Torres, Cornell University)

12 Vaccination is a partial solution to FMD control Does US have an effective response to a nationwide FMD epidemic? Too many strains of FMD for universal vaccine Not enough veterinarians to administer vaccine nationwide High density of herds at some regions Vaccine produces same antibodies as FMD, therefore vaccinated animal and its products are not exportable

13 WHAT IF. Agro-/Foodterror Simultaneous introduction at multiple sites (sale lots, farms, ranches, feedlots, parks, zoos ) Possible infection of the entire/large part of US livestock population Full cost/damage estimation is impossible Lack of preparation/readiness concluded at multiple bio-terror exercises/simulations

14 FMD in the Americas 1870 FMD introduced to: USA Argentina Brazil Eradicated in: USA 1929 Canada 1952 Mexico (Courtesy of Dr. Alfonso Torres, Cornell University)

15 FMD Status by 2000 FMD-free countries Chile (1988) Argentina (1999) Uruguay (1994) Guyanas FMD free with vaccination Paraguay Areas in Colombia Areas in Brazil (Courtesy of Dr. Alfonso Torres, Cornell University)

16 But then - FMD outbreaks * * To August 2003 Venezuela: Colombia: Guyana: Ecuador: Peru: Brasil: Bolívia: Paraguay: Chile: Uruguay: (Courtesy of Dr. Alfonso Torres, Cornell University) Argentina:

17 FMD Control Programs in South America Limited stamping-out Vaccination programs Vaccines are type or sub-type specific Focused, ring and national vaccination campaigns Routine vaccination of cattle only (every 6 months for 1 st 2-3 vaccinations and annually afterwards) Emergency vaccination of cattle, sheep and swine

18 Contrast of 2001 FMD UK Uruguay Outbreaks 2030 outbreaks Culled 5.7M 36 weeks long No vaccination 2057 outbreaks Culled 6.9K 18 weeks long Vaccination (Courtesy of Dr. Alfonso Torres, Cornell University)

19 THERE MAY BE A BETTER WAY Rapid, safe, affordable, easily implemented, efficacious treatment responding to an FMD outbreak and/or to other contagious animal diseases? Interferon α (IFNα) is known to enhance the mammalian immune system and can increase immune resistance to various diseases including FMD

20 ORAL INTERFERON (IFNα)

21 IFNα POTENTIAL for FMD prevention and control Can be administered to livestock in feed Raises immunity against all strains Low cost to animal producer ~25 cents/animal/day Low/specific dose... but medium and higher doses also need study No skilled labor needed No antibodies that confuse infected with protected/ treated animals National pre-emptive responsive program feasible

22 IFNα POTENTIAL for FMD prevention and control Available well-defined human interferon (HuIFNα) HuIFNα is stable in anhydrous crystalline maltose HuIFNα to be approved by Japanese Government for oral use in cattle Mouse and swine studies on efficacy of oral HuIFNα against FMD (latest swine studies at Plum Island)

23 Concept on FMD Prevention and Epidemic Control Quarantine Ring vaccinate Provide IFNα with feed to livestock within quarantine ring(s) and beyond Minimize animal destruction Use the network and daily connection of feed mills to farms/ranches/livestock for rapid distribution of feed with interferon

24 Concept on FMD Prevention and Epidemic Control Setup strategically located storage of IFNα During times of suspected or known FMD outbreak commercial feed mills mix IFNα with animal feed and sell to livestock producers for immediate feeding Feed sold and delivered to producers on credit secured by the US Government Continue animal feeding with IFNα until the risk of further epidemic spread is eliminated

25 Other applications of oral Interferon Possible expansion of concept: Other cattle diseases Other beneficiaries: Swine (swine fever, PRRS) Poultry (Avian Influenza, )

26 Acknowledgements Dr. Joseph Cummins Amarillo BioSciences Dr. Alfonso Torres Cornell University