Foot and Mouth disease (FMD) is one of the most infectious virus diseases known. It is a disease of cloven-hoofed animals, such as cattle, pigs, sheep, goats, and deer. It causes blisters or vesicles of the mouth and of the coronary band at the top of the hoof. The virus is capable of rapidly infecting large numbers of animals, but death rates are generally low. Animals with FMD usually recover uneventfully, but the highly infectious nature and rapid spread of the virus have profound economic consequences.

Part of the economic impact stems from production losses in intensive production systems, such as the dairy industry, where cattle may experience chronic mastitis, poor growth, and permanent hoof damage. An FMD outbreak leads to international economic sanctions, including the loss of export markets. In addition, an outbreak of FMD can severely affect other industries, such as the tourist industry, as restrictions are placed on the movement of people and animals. This was the case in the 2001 outbreak in the United Kingdom.

FMD can spread through contact with contaminated objects, such as clothing and equipment; inhalation of airborne virus; and contact with carrier animals, including birds and rodents. An important mode of entry into an uninfected country such as the United States is through illegal importation of animal products. These products are sometimes fed to animals such as pigs as food waste. The virus multiplies in the new host and an outbreak begins.

Contaminated food scraps are believed to be the cause of the disease outbreaks in the United Kingdomand Taiwan,costing both countries billions of dollars.

Endemic Areas

Asia, Africa, and parts of Europe and South America. The United States and Canada are considered free of this disease. The last outbreak in the U.S. was in 1929.

Clinical Signs

• Blisters/vesicles on the muzzle, tongue and nose
• Blisters/vesicles at hoof/foot junction (coronary band)or between the digits
• Excessive salivation
• Anorexia (poor appetite)
• Lameness
• Abortion
• Decreased milk production
• Sudden death in newborns from inflammation of heart muscle (myocarditis)

Pigs are considered amplifiers of FMD because they exhale large amounts of virus, which can spread by air movement over large distances. Cattle are considered a sentinel species because they exhibit textbook clinical signs of FMD. Sheep are considered a maintenance species because they often have very mild, if any, clinical signs of the disease, but serve to keep the outbreak active.

Treatment

There is no specific treatment for FMD. Any animal suspected of having FMD should be reported to the State Veterinarians or USDA Area Veterinarian in Charge immediately. In the event of a positive FMD diagnosis, the United States will begin eradication plans that include stamping out and/or ring vaccination procedures. Under the stamping-out procedure, all premises with infected livestock will be placed under quarantine with animal movement restricted. To prevent the spread of the disease, all infected animals and animals in contact with infected animals will be slaughtered, and the owner will receive financial compensation from the federal government.

Prevention

The main protection against FMD entering the United States is vigilance at the borders. This includes quarantine of live animals and inspection and source verification of meat and dairy products that could carry the virus into the country. An important facet of disease security is education of travelers who may illegally import animal products purchased overseas; these products could enter the animal feed supply.

Spread of FMD within the U.S. may be prevented by following basic farm biosecurity procedures. These procedures include quarantine for any animal coming into the herd and control of animal, vehicle, and human movement onto the farm. In states where it is legal to feed food waste to pigs, regulations for processing garbage by boiling must be followed.

The United States does not conduct preventative vaccination against FMD. In part, this is because animals' antibodies to the vaccine could be confused with antibodies from a disease outbreak, making identification of infected animals difficult. However, vaccination is an option during a disease outbreak to help confine the outbreak to as small a geographic area as possible. Stockpiling vaccines for future use is complicated by the large number of strains of FMD virus and inability to predict which strain will cause the next outbreak.

Public Health

Transmission of the disease from animals to humans is exceptionally rare (one reported case in the UK in 1966) and is not considered a public health threat by the Center for Disease Control and Prevention (CDC). Foot and Mouth Disease is not the same as Hand, Foot, and Mouth Disease in humans.

Links

Iowa State University-FMD Fact Sheet

USDA-APHIS-FMD FAQs

OIE-Foot and Mouth Disease

EDEN-Foot and Mouth Disease Issues Page

Foot and Mouth Disease Photos

CDC-Hand, Foot and Mouth Disease