Mad, Mad Cow Disease
Pet Care Corner   by Becky E. Marks, DVM

Mad Cow Disease is a current topic, especially in the Northwest. The Disease has potential to be very dangerous. Appropriate steps can ensure your safety. Help is on the way.
The recent identification of Mad Cow Disease on the dairy in Washington put a scare in all of us meat eaters.  The source has been identified. We rest easy again. As with many public health issues the concerns get blown out of proportion. The facts get twisted and the public panics. Soon you have an outbreak of panic.  Mad Cow Disease or Bovine Spongiform  Encephalopathy (BSE) is a unique virus containing an abnormal self replicating  protein called a prion. It is unique because it contains no nucleic acid . Once it enters the host      ( innocent cows in this case) it can change form. The host then becomes protected by the hosts own protein. BSE is one of the encephalopathies(brain diseases) belonging to a family known as the Transmissible Spongiform Encephalopathies (TSE). This includes several individual viruses affecting its own species eg. Sheep , deer and elk, cats , mink and humans.  One syndrome causes a fatal insomnia- and you thought you had it bad?

All of these viruses have five common characteristics :
a.  A long incubation (pre-symptomatic) period from months up to 8 years
b.  The disease progressively causes fatal neurologic damage.
c.   A unique structure called scrapie associated fibrils (SAF) is seen under electron microscope
d.   One of the changes includes vacuolation (holes) in the brain tissue
e.   To date no immune system response is stimulated .

Until now.  Just January 6th this month a new Live blood test has been commercially introduced. Live is emphasized because testing has been performed but the animals had to be slaughtered in order to retrieve specimens for testing. The Gene Thera Inc.  company has developed a test that will begin use this spring. What a break through! The condemnation of uninfected  animals will cease.


The reality is that in the worst case scenario the disease can be spread. It is transmitted through the consumption of BSE-contaminated meat and bone meal supplements in cattle feed. BSE has not been scientifically linked to the Human disease form. It is highly likely but there is still some doubt. However the human disease risk is  death. The sheep disease has been around for over 300 years and thus has never shown to be a human health risk. There have been 180,000 cattle  cases abroad since 1986 with the highest concentration in the United Kingdom. The number of cases peaked 10 years ago. Currently abroad less than 100 cases are reported a week. It is difficult to determine how human cases have resulted from eating animal protein.

In the meantime cattle are not permitted to be fed mammalian protein.  The importing of cattle comes from countries of low risk.  Certain animal product used in the cosmetics industry can not be imported. Any cattle presented with neurologic signs are not used in human food. The USDA has a high level of surveillance in place. Meat, blood and milk are not known to carry the disease. Brain  tissue can be infected.

The virus does exist in the cattle industry. With the new testing available the USDA will have a scientific grasp on diagnosing the disease. Our surveillance of the meat industry continues to protect us here in the United States. For now avoid eating any brain tissue.