The Meat-and-Potatoes Approach to Bioterrorism

“We now inspect less than 1 percent of the food that comes into this country,” stated Deputy Health and Human Services Secretary Claude Allen in February 2002. This shows the tremendous vulnerability of our food supplies to bioterrorism.[1] Even with the addition of 700 new food inspectors, the inspection rate will rise only to 3%.

Discussion of the bioterrorism threat has emphasized aerosols, the preferred method of disseminating biological or chemical agents as a weapon of war. The food and water of an enemy in open field positions would not be easily susceptible to contamination. However, in terrorism, the purest form of asymmetric warfare, the opposite is true. Contaminating the unguarded food supply, whether indigenous or imported, would be much easier than making an aerosol chemical or biological agent.

Although the ultimate goal of terrorism may be to destabilize a country’s infrastructure or government, some terrorist acts may be designed purely to spread panic. Hysteria could overburden all social, economic, and governmental systems, resulting in anarchy and bringing economic production to a standstill. We have seen what a few ounces of anthrax can do to our postal system.

If numerous food-borne outbreaks occurred across the country, people would soon fear their meals. They would worry about botulinum toxin in their green salad at home or at the restaurant salad bar. They would worry that shigella might be in their Mexican or Chinese takeout. What about the toxogenic E. coli in the milk or the salmonella in the ice cream at dessert? Unfortunately, people have reason to worry: all these contaminations have occurred naturally every year.[2] If Mother Nature can do this repeatedly, then a terrorist should have no problem recreating these outbreaks over and over in any number of American cities.

Terrorists don’t need to resort to exotic agents to cause mass casualties. Normally occurring viruses, bacteria, and toxins are readily accessible and easy to grow or make. Even Third World parasites would be quite effective, since Americans’ fear of these parasites by is far greater than the medical risk. Hepatitis A would probably be just a one-time agent since immunization against this virus is possible. However, it would necessitate a national immunization campaign that would tax a system already strained by other outbreaks.

Furthermore, medical services in the United States have been streamlined, and little surge capability exists. Few cities can adequately handle several hundred extra cases of infectious disease or trauma. This fact will increase people’s anxiety.

With our largely unmonitored food supply, the problem with protecting ourselves from bioterrorism is that the United States does not do well detecting and reporting its own naturally occurring food-borne outbreaks. According to the Centers for Disease Control (CDC), only 32% of the reported outbreaks have a known etiology.[3] The number of outbreaks is also much higher than is reported. It is estimated that 1.4 million salmonella infections occur each year, but the CDC gets reports of only about 38,000 annually.[4] Terrorist groups could use infectious disease agents to confuse public health officials into believing that outbreaks were naturally occurring.

One of the largest naturally occurring food-borne outbreaks in U.S. history happened in 1994, when a national brand of ice cream became contaminated with salmonella enteritidis at the factory. Some 220,000 persons were infected.[5]

The one known case of intentional contamination of food by a radical group, the Rajneeshees, in 1984 caused 751 cases of salmonella typhimurium in a small town in Oregon. In a trial run to see whether their idea worked, they contaminated several restaurant salad bars with salmonella they had isolated from standard hospital laboratory antibiotic sensitivity disks purchased from a Seattle medical supply company.[6] After this trial run, they were planning on using a much more dangerous salmonella that causes typhoid fever. The intentional nature of this outbreak wasn’t discovered until a year later when a cult member confessed the incident to the local police. This was after a complete CDC investigation that could not determine the cause. (The same strain of salmonella the Rajneeshees used caused an outbreak of 16,000 confirmed cases in the Midwest in 1985 when post-pasteurized milk became contaminated; an estimated 170,000 people were affected.[7, 8])

The 1982 Tylenol tampering killed seven people by cyanide poisoning,[9] and cyanide-laced medications were found again in 1987 and 1991.[10, 11] Even though tamper-proof packaging is now standard on many items, syringes could be used to directly contaminate already-packaged foods.

The ease of tampering is exacerbated by the potential for wide dissemination of contaminated products. Our food production is becoming more and more centralized and its products distributed over wide geographic areas, both inside the country and abroad. Food that has been tampered with could be widely and quickly distributed.

Probably the easiest portion of our agricultural system to compromise but the most difficult to protect from bioterrorism is our crops. Several plant diseases that exist outside the United States could devastate our crop exports and drastically reduce food for our livestock and our personal consumption. Lists of potential bioterrorism agents for plants have been developed similar to the bioterrorism agent lists for humans and animals.[12, 13] These lists show that viruses, fungi, and bacteria could seriously affect major grain crops such as corn (two major threats), sorghum, and rice (two major threats). Such pests would marginalize food staples such as the potato, tomato, and soybeans. Five diseases on this “most dangerous list” target our citrus crops.

Some have downplayed this type of bioterrorism, saying that since it has never happened and since it would take a concerted effort, it would be unlikely to occur.[14] This may have been a safe supposition before the World Trade Center disappeared from the New York skyline. The same coordinated long-term planning necessary for the 11 September attack makes this type of terrorism a real possibility.

No food product would be safe. Fresh vegetables and fruits would probably be the easiest to intentionally contaminate. Fresh-produce wholesalers and distributors are notorious for employing illegal immigrants and for not checking background information on their employees. It would not be difficult for a terrorist to pose as an employee and, using a sprayer attached to a garden hose, wet down several hundred tons of lettuce with salmonella or hepatitis A. Even processed foods wouldn’t be safe. Terrorists could use heat-stable toxins that would survive the packaging process.

However, what if these techniques were coordinated throughout our food system at both the production and consumer ends? As more of our food becomes imported, especially hard-to-clean off-season fruits and vegetables, bioterrorists don’t even have to be inside the United States to do damage. In 1997, strawberries imported from Mexico contained cyclospora and caused 153 cases of hepatitis A.[15] Cyclospora was implicated in diarrheal outbreaks caused by infected imported raspberries during the late 1990s.[16, 17]

Bioterrorism is worrisome not only on a health level, but on an economic one as well. If a bioterrorist attack had the impact that foot-and-mouth disease has had in the United Kingdom, the results could be enormous. In August 2001, the BBC reported that foot-and-mouth disease could cost the British economy up to $6 billion.[18] Later, a Canadian newspaper estimated the total British loss at nearly $20 billion.[19] The 1997 Taiwan foot-and-mouth outbreak cost $4 billion for eradication and disinfection and $15 billion in lost export revenues.[20] In 1999 a computer model at the University of California–Davis was developed to measure the effect that an outbreak of foot-and-mouth disease would have on the economy of Tulare County, CA.[21] It was posited that the direct cost to the county would be $500 million to $1.5 billion. Another loss of about $1.9 billion would occur if other countries banned California animals and meat. If the ban included the entire United States, the embargo costs would reach $8.9 billion.

Two major bird flu epidemics in Hong Kong during 1997 and 2002 caused the termination of hundreds of thousands of chickens that had the potential of spreading a new form of influenza to humans.

One step to combat the bioterrorist threat is for the United States to have a national disease surveillance system that could not only help uncover a terrorist attack but also recognize naturally occurring outbreaks that now go undetected. Even if a bioterrorism attack never occurs, this type of health surveillance will spot disease outbreaks or associations quickly and will in turn reduce the national disease burden for humans, plants, and animals. With the ease of electronic communication, there should be daily monitoring of disease patterns across the country at the local, regional, and national levels.

The other step needed to combat bioterrorism comes from new technology. Existing science can diagnose multiple diseases quickly, cheaply, and easily. A diagnostic gene chip covering all major diseases could give the health care provider instant diagnoses. Similar gene chips could monitor the health of livestock, poultry, and crops. Chips could be used during various steps of food processing to ensure quality control and food safety.

This war on terrorism has illuminated the need for improving our health and economy. The systems we develop to combat terrorism will also provide a much-needed health and agricultural infrastructure for the nation as a whole.

Click on an end note to return to the article.

1. Michael Kilian, “America’s Food Supply Vulnerable to Terrorists, Official Says,” Chicago Tribune, 26 Feb. 2002.

2. Jeremy Sobel, Ali S. Khan, and David L. Swerdlow, “Threat of a Biological Terrorist Attack on the US Food Supply: The CDC Perspective,” The Lancet, Vol. 359, No. 9309, 9 March 2002, pp. 874–880.

3. “Surveillance for Foodborne Disease Outbreaks—United States, 1993–1997,” Morbidity and Mortality Weekly Report, 17 March 2000, Vol. 49 (SS01), pp. 1–51.

4. Paul S. Mead et al., “Food-Related Illness and Death in the United States,” Emerging Infectious Diseases, Vol. 5, No. 5, September–October 1999, pp. 607–625.

5. Thomas W. Hennessy, M.D., et al., “A National Outbreak of Salmonella Enteritidis Infections From Ice Cream,” New England Journal of Medicine, Vol. 334, No. 20, 16 May 1996, pp. 1281–1286.

6. Jonathan B. Tucker, ed., Toxic Terror: Assessing Terrorist Use of Chemical and Biological Weapons (Cambridge, MA: MIT Press, 2000).

7. Food and Drug Administration Bad Bug Book, entry for salmonella.

8. C. A. Ryan et al., “Massive Outbreak of Antimicrobial-Resistant Salmonellosis Traced to Pasteurized Milk,” Journal of the American Medical Association, Vol. 258, No. 22, 11 Dec. 1987, pp. 3269–3274.

9. K. A. Wolnik et al., “The Tylenol Tampering Incident—Tracing the Source,” Analytical Chemistry, Vol. 56, 1984, pp. 467A–474A.

10. R. M. Varnell et al., “CT Diagnosis of Toxic Brain Injury in Cyanide Poisoning: Considerations for Forensic Medicine,” American Journal of Neuroradiology, Vol. 8, 1987, pp. 1063–1066.

11. “Epidemiological Notes and Reports Cyanide Poisonings Associated With Over-the-Counter Medication—Washington State, 1991,” Morbidity and Mortality Weekly Report, Vol. 40, No. 10, 1991, pp. 161, 167–168.

12. L. V. Madden, “What Are the Nonindigenous Plant Pathogens That Threaten U.S. Crops and Forests?” American Phytopathological Society, October 2001.

13. N. W. Schaad et al., “Crop Biosecurity,” American Phytopathological Society, September 1999.

14. Jason Pate and Gavin Cameron, “Covert Biological Weapons Attacks Against Agricultural Targets: Assessing the Impact Against U.S. Agriculture,” Belfer Center for Science and International Affairs discussion paper 2001-9, Executive Session on Domestic Preparedness contribution ESDP-2001-05, John F. Kennedy School of Government, Harvard University, August 2001.

15. “Hepatitis A Associated With Consumption of Frozen Strawberries—Michigan, March 1997,” Morbidity and Mortality Weekly Report, Vol. 46, No. 13, 4 April 1997, pp. 288, 295.

16. Barbara L. Herwaldt, M.D., et al., “An Outbreak in 1996 of Cyclosporiasis Associated With Imported Raspberries,” New England Journal of Medicine, Vol. 336, No. 22, 29 May 1997, pp. 1548–1556.

17. Barbara L. Herwaldt, M.D., et al., “The Return of Cyclospora in 1997: Another Outbreak of Cyclosporiasis in North America Associated With Imported Raspberries,” Annals of Internal Medicine, Vol. 130, No. 3, 2 Feb. 1999, pp. 210–220.

18. “FMD Report: Outbreak’s Economic Impact,” BBC News, 29 Aug. 2001.

19. Gerry Klein, “Animals Vulnerable to Bioterror Attack, Researcher Says: Panel Urges Canada to Take Steps to Protect People, Livestock,” Saskatoon (Saskatchewan) StarPhoenix, 7 November 2001.

20. Mark Wheelis, “Agricultural Biowarfare and Bioterrorism,” Edmonds Institute, presented at the Annual Meeting of the Association of Politics and Life Sciences, Atlanta, September 1999.

21. Javier Ekboir, “Potential Impact of Foot-and-Mouth Disease in California,” University of California Agricultural Issues Center, 1999.