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By
Richard H. Bennett, Ph.D.
Expert in Infectious Disease Microbiology
Over the last year, medical professionals and customers alike have
raised questions about the safety of Transfer Factor™ products. Many of the questions are about TSE's. This concern arises from the events
that have taken place in England over the last 14 years.
In 1986 over 160,000 cases of bovine neurological disease were
confirmed in sick cattle. The disease is called Bovine Spongiform Encephalopathy or BSE. The common linkage of this disease outbreak
was the practice of feeding rendered animal waste products back to beef cattle. The infective agent is likely a Prion or a viral-like particle.
The agents that cause TSE's have not been fully identified. Just the same the BSE agents withstand heat processing of normal cooking and
pasteurization. Once ingested they have the ability to infect cells, especially neurological tissues, and reproduce themselves.
The BSE agent is highly species specific as it infects the bovine almost
exclusively. The concern about BSE and human health arose from a statistical linkage that suggested that a variant of the BSE agent was
able to cause the human equivalent of BSE called Creutzfeldt-Jakob Disease or CJD. CJD has a genetic predisposition component and
occurs worldwide at a rate of 1 per million persons. CJD has been linked to the use of Human Growth Hormone (HGH) use and
transplantation of neurological tissue.
In England a variant form of CJD was identified in 14 patients as of
1996. In contrast to typical CJD, this variant affected young patients.
Rigorous scientific review concluded that no definite link between BSE and the CDJ variant could be established. Circumstantial evidence
suggested that consumption of meat containing the BSE agent was the likely cause. Thousands of English and European consumers were
likely exposed, yet only 14 human cases have been confirmed. Milk and dairy products did not appear to be a linkage to the disease and
are considered safe by UK authorities.
Worldwide surveillance for BSE reveals there are a few other countries
that have low incidence of BSE in cattle. THERE HAVE BEEN NO CASES OF BSE IN THE UNITED STATES. Internal surveillance for
BSE is intense due to the potential devastating impact of the disease on the milk and meat industries.
There are TSE's in other animals in the US, including cats, mink, deer,
elk, sheep and goats. There is no evidence of horizontal transmission to humans from these species.
The US meat and milk supply is considered by the USDA and WHO
to be free of the BSE agent. Most importantly protections are now law.
BSE is a noticeable disease and veterinarians are required to report suspect cases. Hundreds of cattle brains in the US are examined each
year for evidence of BSE. There have been no confirmed cases from
this screening process.
In August of 1997 the FDA instituted regulations that prohibit the
refeeding of most animal proteins to cattle and other ruminants. Feeding
animal protein to milk cows has never been recommended and has not been the practice of the dairy producer.
In summary, we should have great confidence that all colostrum and
bovine sources of thymus protein are not contaminated with the BSE agent. The programs and regulations currently in place will work
effectively to ensure product safety for 4Life™ products derived from animal sources.
Sources: WHO Fact Sheet No. 133, Bovine Spongiform Encephalopathy
www.who.int/inf-fs/en/fact113.html
USDA, APHIS, Bovine Spongiform Encephalopathy
www.aphis.usda.gov/oa/bse
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