Myth: BSE is a Common Threat to Animal and Human Health
The incidence of Bovine spongiform encephalopathy (BSE) worldwide has decreased significantly to a fraction of their peak levels in the early 1990s. Back then, there were tens of thousands of animal cases in the UK alone.1 In 2013, worldwide there were seven reported cases, none in the U.S. and none in Canada.2 In fact the World Organization for Animal Health designated U.S. BSE status as negligible risk the lowest risk classification.3
The U.S. has a multiple firewalls strategy to prevent BSE.4 The FDA has banned feeding cattle protein derived from ruminant animals because this was identified as a risk factor for BSE. When cattle arrive at a processing facility, they are inspected by veterinarians looking for signs of the disease. If an animal shows any potential sign of the infection, it is not processed for meat. And when cattle are slaughtered, tissues or organs are removed that could carry disease are removed by trained personnel. These include skull, brain, trigeminal ganglia, eyes, spinal cord and the dorsal root ganglia from cattle 30 months of age and older as well as small intestine and tonsils from cattle of all ages.
The most recent U.S. BSE cases were considered to be the atypical variety. Typical is used to describe a case of BSE when an animal has contracted the disease through one of the common risk factors such as transmission through feed. Atypical cases may be a distinct strain of prion disease. Unlike typical BSE, cases of atypical BSE may occur spontaneously and they are very sporadic, similarly to how dementia occurs in humans.
There have been only 60 cases of atypical BSE worldwide and only among older cattle A World Organization for Animal Health review panel studied atypical BSE and concluded that the risk was no different than for BSE and no changes were needed in the measures that protect animal and human health from this disease.4
If beef from an infected animal did get through the multiple firewalls designed to prevent BSE, people would not be at risk from eating it. The BSE agent accumulates primarily in brain and spinal cord tissue in infected cattle. Evidence suggests that the same agent causes BSE and variant Creutzfeldt - Jakob Disease, the neurological disorder that affects humans. However, vCJD is not the same as so-called “sporadic” CJD, which strikes older people worldwide at a rate of about one in every million people for unknown reasons. About 200 cases of variant CJD have been identified worldwide since BSE was first recognized in 1986. Most have occurred within the United Kingdom. It is widely believed consumption of BSE infected tissue is the cause of BSE. This underscores how rare the disease is and lends support to the theory that development of variant CJD may require a combination of exposure to the BSE agent and a certain genetic predisposition. In the United States, brain, spinal cord and other specified risk materials are banned for human consumption.