Foot and Mouth Disease
There is a limited vaccine for foot and mouth disease. The vaccine consists of killed viruses. The viruses are unable to cause the disease, but stimulate the immune system to form the antibodies that will help protect a vaccinated animal from developing the disease. The full promise of a foot and mouth vaccine has not yet been fulfilled, however. This is because there are seven different types of the foot and mouth disease virus. Furthermore, these types have multiple subtle differences. As of 2002, a single vaccine that is capable of stimulating immunity to all these different versions of the virus does not exist.
Vaccination against foot and mouth disease must be accomplished each year to confer protection to the virus. The cost of an annual vaccination of the domestic cattle, sheep, and swine of any country would run to the many millions of dollars. And the vaccine protects an animal from developing symptoms, but not from acquiring the virus. Thus, a vaccinated animal could acquire the virus and pass the virus on to other animals that were not vaccinated.
For the reasons of cost and the possible contribution of vaccination to the spread of the disease, the widespread use of foot and mouth vaccine has not been sanctioned. It is conceivable that future versions of the vaccine will be modified using the tools of biotechnology to provide long lasting immunity.
United States Food and Drug Administration, Veterinary Services Emergency Programs, 4700 River Road, Unit 41, Riverdale, Maryland 20737–1231. January 2002 [cited November 6, 2002]. <http://www.aphis.usda.gov/oa/pubs/fsfmd vac.html.>.