What Is the Risk of vCJD From the Administration of a Vaccine?
Question
What is the risk of transmitting variant Creutzfeldt-Jakob disease from vaccines that use bovine-derived materials from countries where bovine spongiform encephalopathy exists?
N. Indich, MD
Response
from Robert W. Steele, MD, 03/20/01
Bovine spongiform encephalopathy (BSE) is a progressively degenerative neurologic disorder of cattle. Now commonly referred to as "mad cow disease," this disease was first recognized in England in the 1980s. In 1996, human transmissible spongiform encephalopathy, also known as variant Creutzfeldt-Jakob Disease (vCJD), was recognized in the United Kingdom.[1] Further epidemiologic evidence suggested that vCJD was associated with the ingestion of beef products from cattle containing the BSE agent.[2]
In 1993 and again in 1996, the US Food and Drug Administration (FDA) stated its recommendations that vaccine manufacturers not use materials derived from cattle born, raised, or slaughtered in countries where BSE is known to exist. A list of these countries, as well as countries where import requirements and surveillance are considered inadequate, is kept by the US Department of Agriculture (USDA; Table 1).[3]
Despite this recommendation, bovine-derived materials are used in multiple pharmaceutical products, and, this year, the Center for Biologics Evaluation and Research of the FDA discovered several vaccines were being produced using bovine materials from animals on the USDA's list (Table 2).[1] However, there have been no reports of vCJD associated with administration of biological and pharmaceutical products containing these bovine-derived materials.[4]
Nonetheless, realizing that contamination of these products is a potential problem, the FDA requested all vaccine manufacturers replace their products made with bovine-derived materials from unknown sources or on the USDA's list with bovine-derived materials from countries not on the USDA's list as a precautionary measure.[5] All manufacturers have agreed to do this, and full replacement is anticipated within the year.
To assess the potential risk of transmitting the BSE agent through vaccines, several factors have to be considered:[1]
The time period, country of origin, specific herd, and animal husbandry procedures that were used with the cattle
How infective the materials are that were used in production
How much bovine-derived material was present in the final vaccine product
These issues were discussed in a recent joint meeting with the Transmissible Spongiform Encephalopathy Advisory Committee and the Vaccines and Related Biological Products Advisory Committee, where it was concluded that the risk of transmitting vCJD through vaccines is theoretical and remote.[1] At this time, benefits of vaccination are considered much greater than the remote risk of contracting vCJD through immunization.[1,6]
Table 1. Countries That Have Reported Bovine Spongiform Encephalopathy
Great Britain
Belgium
Denmark
France
Germany
Ireland
Italy
Luxembourg
Liechtenstein
The Netherlands
Northern Ireland
Portugal
Spain
Switzerland
Oman
The Falkland Islands
Canada
The Azores
Table 2. Current List of Vaccines Using Bovine-Derived Materials From Countries on the USDA's BSE List or From Unknown Countries
Vaccines that use bovine-derived materials from countries on the USDA's list:
Aventis Pasteur, S.A.'s Haemophilus influenzae type b conjugate vaccine, ActHIB
(ActHIB is also marketed as OmniHIB by SmithKline Beecham Pharmaceuticals)
North American Vaccine Inc.'s diphtheria and tetanus toxoids and acellular pertussis
(DTaP) vaccine, Certiva
References
Center for Biologics Evaluation and Research. Bovine spongiform encephalopathy (BSE). Available at: http://www.fda.gov/cber/BSE/BSE.htm#usda
Spongiform Encephalopathy Advisory Committee of UK statement of 20 March 1996. Available at: http://www.maff.gov.uk/animalh/bse/index.html
USDA Code of Federal Regulations, title 9, part 94 (9 C.F.R. part 94).
Minor PD, Will RG, Salisbury D. Vaccines and variant CJD. Vaccine. 2000;19:409-410.
Notice to readers: public health service recommendations for the use of vaccines manufactured with bovine-derived materials. MMWR Morb Mortal Wkly Rep. WeeklyDecember 22, 2000;49:1137-1138.
Centers for Disease Control and Prevention. Update: vaccines and bovine spongiform encephalopathy (BSE). Available at: http://www.cdc.gov/nip/vacsafe/concerns/bse/default.htm
Call me paranoid but I wonder about BSE being covered up here in the US. This resonates of the same sort of propaganda that we have already been bombarded with concerning autism. Or is it just me?