Foot-and-mouth disease (FMD) is a severe,
highly communicable viral disease of cattle
and swine. It also affects sheep, goats, deer,
and other cloven-hooved ruminants. FMD is
not recognized as a zoonotic disease.
This country has been free of FMD since 1929,
when the last of nine U.S. outbreaks was eradicated.
The disease is characterized by fever and
blister-like lesions followed by erosions
on the tongue and lips, in the mouth, on the
teats, and between the hooves. Many affected
animals recover, but the disease leaves them
debilitated. It causes severe losses in the
production of meat and milk.
Because it spreads widely and rapidly and
because it has grave economic as well as clinical
consequences, FMD is one of the animal diseases
that livestock owners dread most.
What Causes It
The disease is caused by a virus. The virus
survives in lymph nodes and bone marrow at
neutral pH, but destroyed in muscle when in
pH<6.0 i.e. after rigor mortis. The virus
can persist in contaminated fodder and the
environment for up to 1 month, depending on
the temperature and pH conditions.
There are at least seven separate types and
many subtypes of the FMD virus. Immunity to
one type does not protect an animal against
How It Spreads
FMD viruses can be spread by animals, people,
or materials that bring the virus into physical
contact with susceptible animals. An outbreak
can occur when:
* People wearing contaminated clothes or
footwear or using contaminated equipment pass
the virus to susceptible animals.
* Animals carrying the virus are introduced
into susceptible herds
* Contaminated facilities are used to hold
* Contaminated vehicles are used to move
* Raw or improperly cooked garbage containing
infected meat or animal products is fed to
* Susceptible animals are exposed to materials
such as hay, feedstuffs, hides, or biologics
contaminated with the virus.
* Susceptible animals drink common source
* A susceptible cow is inseminated by semen
from an infected bull.
Vesicles (blisters) followed by erosions
in the mouth or on the feet and the resulting
excessive salivating or lameness are the best
known signs of the disease. Often blisters
may not be observed because they easily rupture,
leading to erosions.
Some of these other signs may appear in affected
animals during an FMD outbreak:
* Temperatures rise markedly, then usually
fall in about 2 to 3 days.
* Ruptured vesicles discharge either clear
or cloudy fluid and leave raw, eroded areas
surrounded by ragged fragments of loose tissue.
* Sticky, foamy, stringy saliva is produced.
* Consumption of feed is reduced because
of painful tongue and mouth lesions.
* Lameness with reluctance to move is often
* Abortions often occur.
* Milk flow of infected cows drops abruptly.
* Conception rates may be low.
Meat animals do not normally regain lost
weight for many months. Recovered cows seldom
produce milk at their former rates. FMD can
lead to myocarditis (inflammation of the muscular
walls of the heart) and death, especially
in newborn animals.
Confusion With Other Diseases
FMD can be confused with several similar,
but less harmful, diseases, such as vesicular
stomatitis, bluetongue, bovine viral diarrhea,
and foot rot in cattle, vesicular exanthema
of swine, and swine vesicular disease. Whenever
mouth or feet blisters or other typical signs
are observed and reported, laboratory tests
must be completed to determine whether the
disease causing them is FMD.
Where FMD Occurs
While the disease is widespread around the
world, North America, Central America, Australia,
New Zealand, Chile, and some countries in
Europe are considered free of FMD. Various
types of FMD virus have been identified in
Africa, South America, Asia, and part of Europe.
Prevention and Control
FMD is one of the most difficult animal infections
to control. Because the disease occurs in
many parts of the world, there is always a
chance of its accidental introduction into
the United States.
Animals and animal byproducts from areas
known to be infected are prohibited entry
into this country.
Livestock animals in this country are highly
susceptible to FMD viruses. If an outbreak
occurred in the United States, this disease
could spread rapidly to all sections of the
country by routine livestock movements unless
it was detected early and eradicated immediately.
If FMD were to spread unchecked, the economic
impact could reach billions of dollars in
the first year. Deer and wildlife populations
could become infected rapidly and could be
a source for reinfection of livestock.
What You Can Do
You can support U.S. efforts against FMD
* Watching for excessive salivating, lameness,
and other signs of FMD in your herd; and
* Immediately reporting any unusual or suspicious
signs of disease to your veterinarian, to
State or Federal animal disease control officials,
or to your county agricultural agent.
If FMD should appear in your animals, your
report will set in motion an effective State
and Federal eradication program.
Your participation is vital. Both the early
recognition of disease signs and the prompt
notification of veterinary officials are essential
if eradication is to be carried out successfully.
Your warning may prevent FMD from becoming
established in the United States, or, if it
does spread, reduce the time and money needed
to wipe it out.
For more information about FMD, contact
USDA, APHIS, Veterinary Services
4700 River Road, Unit 41
Riverdale, MD 20737–1231
Telephone (301) 734–8073
Fax (301) 734–7817
The APHIS Emergency Operations Center
Current information on animal diseases and
suspected outbreaks is also available on the
Internet at http://www.aphis.usda.gov.