Blogging About Critters Since 2007

Tuesday, August 7, 2007

Foot and Mouth Disease

As you may have read, there is an outbreak of foot and mouth disease in the UK. The last time this happpened, as many as 10 million animals were slaughtered. Foot and Mouth Disease is not always fatal.

But, it can lead to debilitation, loss of milk, followed by the dreaded....import bans. That in turn, leads to the mass killing of livestock to excise this pox upon livestock economics. For those of you not familiar with the disease, (which included me), here is part of the USDA APHIS fact sheet on foot and mouth disease:

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 other types.

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 susceptible animals.
* Contaminated vehicles are used to move susceptible animals.
* Raw or improperly cooked garbage containing infected meat or animal products is fed to susceptible animals.
* Susceptible animals are exposed to materials such as hay, feedstuffs, hides, or biologics contaminated with the virus.
* Susceptible animals drink common source contaminated water.
* A susceptible cow is inseminated by semen from an infected bull.

No comments: