Foodborne infections: Didn't anyone know?

Salmonella. Escherichia coli 0157:H7. Listeria. Cyclospora.

How many Americans remember seeing those words mentioned with any frequency in the popular press 10, even five years ago? Probably few. Now, however, there rarely is a day when life-threatening foodborne illnesses--or the pathogens that cause them--are not mentioned.

What's responsible for putting heat on media coverage: Are there more incidents of foodborne illnesses, or just more incidents being reported? Maudene Nelson, nutritionist at Columbia's Institute of Human Nutrition, College of Physicians & Surgeons, says that government reports have always provided information about foodborne illness, but data are now more widely available. "Many foodborne illnesses result from mistakes made by people in their homes, but there's also a great deal of emphasis on improving prevention and reporting of commercial outbreaks, brought about by the frequency and severity of cases -- several of which have resulted in deaths."

Within the last few years, newspaper headlines and television documentaries have told the public about tainted raspberries imported from Guatemala; contaminated oysters from Louisiana; cyclospora on California strawberries; and E. coli-laced ground beef from a meat processing plant in Hudson, N.D., resulting in deaths caused by tainted hamburger at a large fast food chain. More recent recalls have involved Listeria monocytogenes in dairy products, chicken burritos, and hot dogs (just in time for baseball season). The International Food Information Council Foundation's content analysis report, "Food for Thought II," indicated that food safety and nutrition issues relating to foodborne illness were the most addressed topics in food coverage in the last year analyzed (1997).

What's happening here? Do we have an outdated system for ensuring food safety, more awareness of foodborne illnesses, better reporting techniques, or better tools to find dangerous pathogens? It would be fair to say "all of the above."

Patrick Moore, M.D., an epidemiologist and pathologist at Columbia, stresses that the food supply has changed dramatically in recent decades. "We now have centralized processing of foods and wide distribution, so when a food is tainted, many people in many locations will be affected, not just a few locally. We may eat produce grown in Colombia, processed in Mexico, and then distributed in Minnesota, allowing many opportunities for pathogens to make their way into the system. We also are eating foods that are different or are prepared differently; for example, pre-packaged sliced cold cuts were not available a generation ago. We can have apples in the winter and tropical fruits that can't be grown in the United States." He also says that the population most affected by even small foodborne infections--the elderly, those undergoing chemotherapy or other immunosuppressive treatments, and HIV-positive persons--has grown, increasing the need for prevention strategies such as washing fruits and vegetables carefully, cooking poultry and meats well, storing food safely, and using a product before its expiration date.

Some observers contend that the government is finally addressing the issues of enforcing existing laws governing imported fruits and vegetables, and others note that officials are finally being called to task to enforce good hygiene practices at feedlots, slaughterhouses, and packing houses. Consumers are paying better attention to food safety at home, avoiding undercooked eggs and meats. There also are better efforts for reporting outbreaks of illness as well as methods of detecting pathogens, such as DNA testing, that were unavailable only a few years ago.

Others, however, worry that reports of problems still may be scattershot thanks to recent "veggie libel" laws, such as those in Texas and 12 other states and pending in nine more, making discussion of "false information that a perishable food product is not safe for human consumption" grounds for a civil damage suit.

It's understandable that food-industry interests would wish to deter scaremongering, but public attention to food hazards has spurred some constructive actions. Late in 1997, President Clinton sought an additional $71 million (approximately 60 percent more than was available when he took office in 1993) for food safety programs at the Department of Agriculture, the Food and Drug Administration, and the Centers for Disease Control and Prevention. This has resulted in the CDC creating the Foodborne Diseases Active Surveillance Network (FoodNet) as part of its Emerging Infections Program, collecting information about outbreaks and estimating the frequency and severity of diseases, as well as the FDA's Hazard Analysis and Critical Control Point inspection system for identifying points where pathogens or toxins could slip into foodstuffs. In May of 1998, the CDC also initiated PulseNet, a network of health laboratories that perform a standardized technique of pulsed-field gel electrophoresis (a DNA "fingerprinting" method) to compare strains of pathogens from tainted food samples and rapidly trace outbreaks to their source.

Progress against some foodborne hazards continues in the academic research sector. Researchers at Washington University in St. Louis and the private vaccine-development firm Megan Health, for example, have developed a technique for vaccinating chickens against salmonella, raising the hope that the broiler chicken industry--which has improved contamination rates, according to the USDA's Food Safety Inspection Service, from 50 percent positive in the 1980s to 10 percent in the past year--may come close to its ultimate goal of zero contamination. There also is strong interest on the part of industry, and some government officials, for irradiating poultry and meats with gamma rays or electron beams.

Still, for all the good news, a food-related scare story remains the kind of bad news that's always good news for the commercial press. These reports are likely to continue, creating visceral impact well beyond the objective frequency of the outbreaks--perhaps making complacent consumers more careful about the food they buy and prepare. --Claudia M. Caruana

Related links...

  • Fact sheet on foodborne infections, National Foundation for Infectious Diseases

  • Foodborne Illness Education Information Center, USDA/FDA

  • Bad Bug Book, FDA Center for Food Safety and Applied Nutrition

  • Atul Gawande, "Gamma Burgers," Slate, September 11, 1997

  • Alan Hall, "Is It Safe to Eat?" Scientific American, November 3, 1997

  • Press release on constitutionality of "veggie libel" laws, American Civil Liberties Union, January 22, 1998

  • Foodspeak Coalition for Free Speech, Center for Science in the Public Interest

  • CLAUDIA M. CARUANA is a free-lance science and medical writer whose work has appeared in 21stC, the New York Times, New York, Saveur, NCRR Reporter (National Center for Research Resources), and other publications. She is the author of Taste of Malta (NY: Hippocrene Books, 1998).

    Photo Credits Microbes: Photo Jonathan Smith / Computer Illo Howard R. Roberts