How Do Foot-And-Mouth Disease (FMD) and Bovine Spongiform Encephalopathy (BSE) Differ?
FMD and BSE are similar in that they both affect livestock. Otherwise, there are major differences between the two animal diseases.
FMD is a highly contagious viral disease that primarily afflicts cloven-hoofed animals (i.e., cattle, pigs, sheep, goats, and deer). Wild ungulates such as buffalo, antelope, and warthogs are also susceptible to the disease. FMD can be debilitating to infected animals, causing losses in meat and milk production. It also can be fatal to young animals.
The principal symptoms of FMD are fever and blisters in the mouth and on the feet, resulting in salivation and lameness. Symptoms are similar in all species, although the severity may vary considerably.
Mortality rates from contracting FMD are generally low. However, an outbreak of the disease can have grave economic consequences for the meat and dairy industry in countries where it occurs. This is primarily due to the imposition of international trade restrictions on affected countries, which often go to great lengths, investing large sums in eradication campaigns, to recover their FMD-free status and resume trade.
FMD is not a public health concern because humans rarely contract the disease, and it causes few or mild symptoms when it occurs in humans. FMD is not a food safety issue because affected animals are easily identified and removed from the food chain, and, additionally, the virus is killed by cooking.
BSE, or “mad cow disease,” on the other hand, has been linked to a fatal brain disease in humans called Creutzfeldt-Jakob disease (CJD). BSE is also a food safety issue in that it appears to result from the consumption of beef products contaminated by central nervous system tissue from infected cattle.
The vast majority of cases of BSE have occurred in the United Kingdom, where, up until 1988, the rendered carcasses of livestock were fed to ruminants and other animals as a protein-rich nutritional supplement. Recognizing that this was a source of infection, the United Kingdom imposed a ban on ruminant protein feed in 1988. Unfortunately the disease had already reached epidemic levels in the United Kingdom and had spread to other countries that imported livestock food supplements or live animals. The incidence of new cases in the United Kingdom has been decreasing in recent years.
BSE, which is also fatal to cattle, has not occurred in the United States or other countries that have historically imported little or no live cattle, beef products, or nutritional supplements from the United Kingdom.
Sources: The Centers for Disease Control and Prevention (CDC) and the Advanced Veterinary Information System (AVIS) Consortium.