Mad Cow Disease Prevention Efforts : Part 2

by Food and Drug Administration (FDA)

(Page 2 of 4)

The second firewall, the USDA's surveillance program to look for BSE in cows, began in 1990. It was through this program that the BSE-infected cow in Washington was found. The USDA has tested more than 20,000 cows for BSE in each of the last two years, and plans on significantly increasing its testing to test every animal in the high-risk cattle population in 2004 and 2005.

Despite this rigorous surveillance program, some people have called for testing all slaughtered cows. But many of these cows are young and the BSE agent doesn't usually show up in animals until after 30 months of age, says DeHaven. "This is a disease with a very long incubation period — typically three to eight years," he says. "To suggest that we would test all animals regardless of age at slaughter is not consistent with the science and what we know about the disease."

"Animals may get exposed at a very young age," says Linda Detwiler, D.V.M., adjunct professor at the University of Maryland. "During the incubation period, the BSE agent replicates in certain tissues of the body and usually after three years makes its way to the brain." The tests used today can detect the infection only in the brain — not in other tissues or blood, so BSE cannot be diagnosed in very young animals, says Detwiler. "The animal may be infected, but it just can't be detected."

Detwiler uses the analogy of looking for a human disease, such as Alzheimer's, to explain the rationale for the current BSE surveillance system. "If you didn't know that Alzheimer's was in the United States, what population would you concentrate on to be able to find it?" asks Detwiler. "Would you start taking brain biopsies from teen-agers, middle-aged, or older people? Testing older folks with dementias increases your chance of finding the disease."

The FDA's 1997 feed rule, which bans most protein from mammals in ruminant animal feed, is the third BSE firewall. In 2001, the Harvard Center for Risk Analysis concluded that the feed rule provided the nation's major protection against BSE becoming established in the United States. In August 2003, Harvard reaffirmed the findings of its initial study and concluded that if infected animals or feed material entered the United States from Canada, the risk of spreading extensively within U.S. herds was extremely low.

The fourth firewall is the additional protective measures recently taken by the FDA and the USDA, and the fifth firewall is the emergency response plan that the agencies initiated immediately after finding the BSE-positive cow in Washington state.

Some critics have suggested that the federal government take further actions, such as tightening slaughter controls and feed regulations, similar to practices used by European governments in their efforts to combat BSE. "You shouldn't equate the actions that the Europeans had to take with the actions that we need to take because the situation in the two continents was very different when BSE was discovered in each continent," says Murray Lumpkin, M.D., the FDA's deputy commissioner for special programs. "In Europe, BSE was at an epidemic stage in their cattle population with ultimately thousands of cases identified. So they had to put in place measures not only to keep BSE from spreading but to contain an epidemic. Based on their experience, we put many BSE firewalls in place before we had any evidence of disease in this country."

Feed Ban Enforcement

Since the feed rule went into effect in 1997, FDA and state inspectors have conducted more than 26,000 inspections involving more than 13,000 firms that handle animal feed.

"Regulations are only as good as your enforcement activities," says Sundlof. When violations are found, the firm must quickly address them and undergo a prompt follow-up inspection. Depending on the nature of the violation, a firm's products could be recalled, it could receive an FDA warning letter that demands a response from the firm about how it will correct the violations, or it could find itself in court. Renderers, feed mills, and protein blenders that process materials prohibited for ruminants are inspected at least annually, and more frequently if they are not in compliance with the rule, says Sundlof.

From 1997 to the end of 2003, 47 feed firms had recalled a total of 280 feed products, the FDA had issued 63 warning letters, and the court had ordered one permanent injunction against a feed company. The recall track record is improving: Only 12 of the 280 recalls occurred during 2003.

Sundlof says a strong education program on the feed rule for industry and inspectors has contributed to the high rate of compliance, which has climbed from 75 percent when inspections first began in 1997 to more than 99 percent today.

"The compliance rate is the highest of any FDA compliance program in all of the categories of products that we regulate," says Acting Commissioner of Food and Drugs Dr. Lester M. Crawford. "It is probably the most effective regulatory program that FDA has had in its 100-year history."

All of the firms involved in the investigation of the BSE-infected cow in Washington were in compliance with the FDA's feed rule.

The agency is stepping up its inspections of feed facilities to further ensure compliance. The FDA, along with state agencies, plans to conduct 6,600 inspections in 2004, several hundred more than the previous year.

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FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.