What is the safest way to dispose of a diseased cow carcassand what does it have to do with the public health?
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AT FIRST BLUSH, THE MATTER of the Texas Natural Resources Conservation Commission v. Dr. Mike Vickers seemed to be much ado about very little. In a hearing held in Austin this past February, the TNRCC, Texas’ environmental protection agency, asserted that Vickers should be fined $9,000 because, on two occasions in 1999, he had illegally burned animal carcasses, animal excrement, and medical materials used in the animals’ care in a pit behind his veterinary clinic outside Falfurrias. Vickers explained that, as the main vet in a multicounty ranching area, he had to dispose of a lot of animals that died, many from zoonotic diseases (infections like anthrax or rabies that can be communicated from animals to humans), and he had always burned them to protect the public health. The hearing was so dull that when an environmental investigator from the TNRCC described the “smoldering bag of feces” he had observed in Vickers’ pit, I thought he’d hit upon an apt metaphor for the whole proceeding.
But the more I listened, the more I realized that the hearing was providing a window onto how complicated the business of protecting the public health has become these days. To begin with, none of this would have shown up on the radar if Vickers, a garrulous 52-year-old with white hair and a matching mustache, had been just any rural vet. But he happened to be the vet who had treated the heifer that had died of the anthrax that was the source of the microbes used in last fall’s bioterrorist attacks.
The way Vickers tells it, he was as shocked as anyone this past January when his friends at the Texas Veterinary Medical Diagnostic Laboratory at Texas A&M called to inform him that government investigators believed the anthrax that killed five people last fall—the so-called Ames strain—had not come from the National Veterinary Services Laboratories in Ames, Iowa, after all but was derived from a cow that had died in Vickers’ care in 1981.
Vickers recalled that he had sent a tissue sample from the dead heifer to the A&M lab—standard operating procedure among Texas vets to verify dangerous contagions like anthrax. He hadn’t given it a second thought for two decades and was unaware that A&M had subsequently sent a culture of that anthrax to the Army’s biodefense lab at Fort Detrick, Maryland, where biologists testing the military’s anthrax vaccine needed fresh germs. The “Ames” confusion arose because a clerk at A&M apparently had added the Fort Detrick address to a preprinted mailing label bearing the address of the Ames veterinary lab (with which A&M corresponded frequently) in such a way that the Ames address appeared to be the return address.
Because this strain of anthrax had been shared with as many as fifty other labs over the intervening years, the revised etiology provided no firm leads to the identity of the bioterrorist. But it did make a minor celebrity of Mike Vickers. Newspapers and TV stations from Houston, Dallas, and Austin called him; so did the Washington Post and the New York Times. And Vickers had more than reminiscences of a dead heifer to share. He had an agenda, most of which concerned his legal clash with the TNRCC. Vickers might have been accused of using his newfound notoriety to get off the hook except that, in the wake of the anthrax mailings, his legal problems raised important questions: What were the established procedures for disposing of this sort of biohazardous waste and were they stringent enough, considering that we now know zoonotic diseases can be effectively weaponized and deployed? And bioterrorism aside, how well were we dealing with the dangers posed by these diseases in plain old peacetime?
The answers seemed especially important in Texas, which probably has more zoonotic diseases floating around than does any other state (although it’s hard to know for sure, since they usually occur in the wild, where statistics aren’t kept). Even those diseases that occur among livestock are hard to track here because the ranches are so large. According to Dr. Max Coats of the Texas Animal Health Commission, “The numbers we have for anthrax and rabies aren’t really that reliable.”
More troubling is the fact that such diseases don’t necessarily disappear when the infected animal dies and decomposes, which is why Vickers was burning the carcasses in the first place. Anthrax spores, for example, can survive in the soil for up to 150 years after an animal has decomposed. The Centers for Disease Control and Prevention has warned of 35 other zoonotic diseases that could pose a danger to humans—everything from brucellosis to hantavirus. According to Vickers, who says he regularly works with animals infected with any one of a dozen of them, simply burying the bodies, whether on private property or in a landfill, isn’t safe “because the germs outlive the carcass.” Even carcasses of animals that died of noninfectious causes can prove hazardous, he adds, since they are frequently incubators for anaerobic microbes, which can live without oxygen and cause infections like botulism and tetanus. “Burning is the only way to make sure all the germs are dead,” says Vickers.
Other authorities I talked to agreed. But as the testimony at Vickers’ hearing revealed, it’s not that simple. The TNRCC considers animal carcasses—diseased or not—to be solid waste that can be, and frequently is, accepted at landfills as long as it is immediately buried beneath at least three feet of soil. But Vickers says that after he was cited for burning in 1999, he checked with nearby landfills to show the TNRCC that he was acting in good faith. None would take diseased carcasses. “It’s one catch-22 after another,” he says.
Indeed. A private rancher can burn a diseased carcass on his own property, no questions asked; but as the owner of a commercial concern—a veterinary clinic—Vickers could not, at least not at the time the citations were issued. However, thanks to an exception to the TNRCC burn code that Senator Judith Zaffirini of Laredo and Representative Rick Green of Dripping Springs pushed through the Legislature last session—in part at Vickers’ urging—rural vets in counties with fewer than 10,000 residents can now burn animal carcasses. But the exception does not cover the burning of animal excrement or the materials used in the animals’ care, which Vickers says are just as hazardous. Finally, it leaves vets in more-populous rural counties with the same unsavory choices: burn diseased carcasses and break the law; send them to a landfill and risk endangering the public health; or give them back to the owner for burial.
At the heart of this matter is the unlikeliest of conflicts between two natural allies: the agencies charged with protecting the environment and those that protect the public health. As recently as thirty years ago, outdoor burning was the primary means of solid-waste disposal in Texas. In the late seventies the federal government banned such burning to protect the air quality, and since then, with a few exceptions, all solid waste has been sent to landfills. No doubt about it, outdoor burning can represent a public-health threat. Last year, when I investigated health care in the border colonias—settlements of immigrants on unincorporated county lands—residents complained bitterly about the burning of everything from tires to animal carcasses near their homes. The fumes from such fires are especially noxious to children in these poor areas, many of whom suffer from asthma caused by exposure to air pollution and dust mites.
At the same time, it’s hard not to sympathize with Vickers’ burn-now-and-ask-questions-later approach. It may be environmentally incorrect, but it is the only way to kill all the germs. The perfect solution, of course, would be to burn animal carcasses in a “clean” way—i.e., in incinerators. The state’s municipal animal control agencies and humane societies have begun doing just that with dog and cat carcasses, according to Coy Willis, the president of the Texas Animal Control Association. Unfortunately, the incinerators they use are too small for horses and cows, and even the TNRCC admits that none of the commercial incinerators in the state are large enough. Beyond that, for vets like Vickers, the cost of buying one is prohibitive.
Senator Zaffirini thinks the next step should be to investigate taking the entire problem of animal disposal out of the hands of the TNRCC and making it the joint responsibility of the Texas Department of Health and the Texas Animal Health Commission. It would then be up to them to ensure that dangerous animal carcasses are disposed of in a way that doesn’t threaten either the public health or the environment.
In June an administrative law judge upheld Vickers’ $9,000 fine from the TNRCC, ruling that he had been entitled to burn the animal carcasses but not the surgical gloves and other materials used in the animals’ care. Even though he had at least partly made his point, Vickers vowed to continue the fight. “I’m going to take them to the mat,” he says.
To that end, he has agreed to testify in a lawsuit filed by McAllen attorney J. W. Dyer in behalf of owners of homes and businesses near a Rio Grande Valley landfill whose owners want to expand it. Flocks of seagulls, egrets, and buzzards pick over the landfill’s garbage—which Dyer believes includes animal carcasses—and then leave their droppings in a nearby reservoir that supplies water to some of the plaintiffs. “The idea that the birds could be carrying anthrax or some other disease back and forth is worrisome,” says Dyer. “This is a situation that proves that Dr. Vickers’ fear isn’t a theoretical abstraction.”