and of course a little FMD info...
Top 10 causes of foot and mouth disease (FMD) transfer and other biosecurity tidbits
On Friday August 3rd 2007, Foot and Mouth Disease (FMD) was confirmed on a beef farm near Guildford, in Surrey in the United Kingdom. The strain of foot-and-mouth disease used at the Pirbright laboratory research complex in Surrey is reported to be identical to that found on the nearby farm. With this recent outbreak of FMD in Britain, it seemed timely to review the ways FMD can be transmitted between animals, herds, and species. Many of the ways FMD is transmitted also apply to other infectious diseases. Now may be a good time to review your own herd biosecurity plan.
Foot and mouth disease can be transferred to susceptible animals when:
1) Animals carrying the virus are introduced into susceptible herds.
2) Contaminated facilities are used to hold susceptible animals.
3) Contaminated vehicles are used to move susceptible animals.
4) Raw or improperly cooked byproducts containing infected meat or animal products is fed to susceptible animals.
5) People wearing contaminated clothes or footwear, or using contaminated equipment pass the virus to susceptible animals.
6) Susceptible animals are exposed to materials such as hay, feedstuffs, hides, or biologics contaminated with the virus.
7) Susceptible animals drink common source contaminated water.
8) A susceptible animal is inseminated by semen from an infected animal
9) FMD can be transmitted by accidental release from a vaccine laboratory.
10) FMD can be released intentionally by bioterrorists.
FMD is a highly contagious viral disease that can rapidly spread throughout the animal population of an area. The disease primarily infects cloven-hoofed animals, including cattle, pigs, sheep, goats, deer, and water buffalo. Other susceptible species include hedgehogs, armadillos and rodents such as rats and mice. The disease is not transferable to people.
FMD is concerning to cattle producers because it can have sizeable economic consequences. Severe economic loss and international trade embargoes can result from an outbreak of FMD. Producers need to know how to recognize the signs of FMD and what they can do to prevent an outbreak.
Consider FMD in animals exhibiting excessive salivation and lameness along with vesicular lesions (blisters) in the mouth, nasal passage, muzzle, feet, and teats. Often the vesicles progress to erosions that can be found in these areas. Other clinical signs are fever, depression, anorexia, watery nasal discharges, decreased milk production, lameness, and reluctance to move.
Sheep and goats are considered maintenance hosts. They exhibit mild disease symptoms. Consequently, the diagnosis may be delayed allowing time for the virus to spread. Pigs are considered amplifying hosts because of the higher concentration of virus particles in aerosols when compared to other species. Consequently, in pigs the disease spreads rapidly. Cattle are considered indicators of the disease because they are generally the first species to show signs of infection, their lesions are more severe and they progress more rapidly. Cattle can carry the FMD virus in their nasal and respiratory tissues for long periods – they can be healthy carriers for 6 to 24 months. Sheep can be carriers for 4-6 months. Pigs are not carriers.
The virus is in the family Picornaviridae and there are 7 immunologically distinct serotypes and over 60 subtypes. In other words, the virus is fairly resilient. In milk, it can survive regular pasteurization, but not ultra high pasteurization. It can survive freezing in tissues and drying in organic material, such as serum. It can remain active for days and even weeks on organic rich material in moist, cool conditions. It is inactivated on dry surfaces and by sunlight.
Aerosol transmission has occurred from bulk milk trucks as well as the human respiratory tract. FMD virus can survive for 24 hours in the human respiratory tract. Humans are not affected by the disease, but they can transfer it. Feeding of infected animal products can transmit the virus by direct contact. Exposure to contaminated objects such as boots, hands or clothing can result in indirect transmission of the disease. The disease can also be transmitted by artificial insemination, contaminated biological and hormone preparations.
The FMD virus is distributed worldwide, and is endemic in Asia, Africa, Middle East, and parts of South America. Epidemics have recently occurred in Taiwan, South Korea, Japan, Mongolia, Britain, France and the Netherlands. North America, Central America, Australia, and New Zealand have been FMD free for many years. There has not been a case of FMD in the United States since 1929.
A quick response is vitally important in containing an outbreak of FMD. State and Federal veterinarians should be immediately informed of any suspected vesicular disease. Keep in mind that animals can begin spreading the virus before visible signs of the disease emerge. For this reason, know who is on you property at all times and make sure people wash their clothes and footwear before traveling to another farm/ranch/property.