A heifer imported from Switzerland managed to jump England’s barriers to bovine spongiform encephalopathy (BSE), but that isolated incident does not mean the United Kingdom’s Mad Cow defenses aren’t in place.
A routine Aug. 23 crosscheck of slaughter and BSE test data found the system missed the Swiss heifer.
Discovering that the heifer slipped through the system came just as “Bite,” the quarterly magazine of the UK’s Food Standards Agency, published, “Whatever happened to mad cow disease?”
Written by FSA’s David Carruthers, the article steps back to 1996 when a fatal brain disease in young adults was linked to a variant of Creutzfeldt Jacob disease caused by BSE exposure.
For the media, it was Mad Cow Disease; for British beef, it was the end of exports; and for Her Majesty’s government, it was the worst-ever food scandal.
The recent heifer incident pales by comparison to the Mad Cow uproar that occurred almost 20 years ago.
FSA says it is very unlikely that the heifer was infected with BSE, and the specified risk material (SRM)–such as the spinal cord–was removed, making any risk to human health extremely low.
Meat from the heifer, which was just over 42 months old, did enter the food supply without BSE testing.
The heifer was imported in December 2009, and was slaughtered at Woolley Bros (Wholesale Meats) Ltd’s abattoir in Holbrook, Sheffield last July 14.
BSE testing is mandatory for cattle born in Switzerland if slaughtered for human consumption at over 30 months of age.
After crosschecks discovered the problem, officials said BSE regulations required that the animal slaughtered before the untested heifer, and the two animals slaughtered after it, should have been removed from the food chain. However, by that time, all the carcasses had been shipped.
FSA has contacted the Netherlands, where three of the four carcasses were shipped. Meat from the other carcass is no longer in the food supply chain.
The Netherlands, coincidentally, recently found through testing its first BSE-infected cow since May 2008.
At the peak of the BSE problem in 1992, there were 37,000 head of cattle in the UK infected with it. That number was cut to 1,400 in 2000, and just 12 last year.
In his newly published article, Carruthers says the “key BSE controls” are the feed ban, SRM controls, and the over 30-month rule banning the sale of older cattle at slaughter.
FSA lifted the OTM rule in 2005.
“Over recent years it has become increasingly clear that the crisis caused by BSE is behind us and that the risk is very low and well controlled,” Carruthers writes in Bite. “The continued decline in risk has enabled further reductions in the controls to be made–for example the age at which cattle must be tested was raised to 48 months from January 2009–and this process is likely to continue in coming years.”
The FSA publication also reports that vCJD deaths peaked in 2000 at 28. Future increases in vCJD deaths are possible due to past BSE exposure. The high-end estimate for vCJD deaths is 136,000, according to modeling forecasts, but those worst-case scenarios appear to be overblown.
“BSE is, however, still with us,” Carruthers cautions. “Cases in cattle continue to be found (12 in the UK last year, and 6 so far this year). Up to three young people per year still, sadly, die of vCJD.
“Recent findings of rare, different forms of BSE risk in older animals suggest sporadic, spontaneous forms of BSE may arise,” he added.
Carruthers says “FSA’s great achievement” was restoring public confidence in food safety, and added that “…we have been very fortunate that BSE does not transmit more easily from cattle to humans.”
The National Prion Disease Pathology Surveillance Center at Case Western Reserve University in Cleveland says one to three million cattle in the UK might have been infected with BSE before it was recognized in 1986.
“The origin of the first case of BSE is unknown, but the epidemic was caused by recycling processed waste parts of cattle, some of which were infected with the BSE agent and given to cattle in feed,” according NPDPSC. Infected cattle and feed exported from the UK led to smaller epidemics in other European countries.
“Compelling evidence indicates that BSE can be transmitted to humans through the consumption of prion contaminated meat. BSE-infected individuals eventually develop vCJD with an incubation time believed to be on average 10 years,” NPDPSC adds.
There has only been one case of vCJD in the United States, but that patient most likely acquired the disease in the UK.© Food Safety News