With attention focused on the danger of salmonella in tainted peanut products, it’s easy to forget that foodborne bacterial poisoning more often results from eating contaminated meat, poultry or raw eggs.
Despite an overhaul of the U.S. government monitoring system that followed a highly-publicized 1993 E. coli outbreak traced to fast food hamburgers that sickened hundreds and killed four, the rate of foodborne poisoning in humans isn’t dropping.
“We have made no progress over the past decade in making the rates go down,” said epidemiologist Ian Williams, chief of the OutbreakNet Team at the Center for Disease Control and Prevention in Atlanta. For example, in 2007, the rate of infection was 14.92 cases of salmonella infection per 100,000 people, missing the national target of 6.8 cases per 100,000 by a wide margin.
Nobody knows exactly how many cases result from eating animal products versus produce such as tomatoes or peppers, but salmonella-related illnesses, which can cause vomiting, severe abdominal pain and diarrhea, can be deadly to infants, the elderly and immune-compromised persons.
Although an estimated 40,000 human cases are officially tallied each year, the real number is something closer to 1.4 million, according to the CDC. Salmonella-related illness is vastly underreported because the bacteria has to be isolated from a patient’s stool sample and reported to health officials. Because most cases of salmonella poisoning resolve themselves in about three to four days without medical intervention, most victims don’t even see a doctor.
While fewer chickens, pieces of beef, and eggs are leaving processing plants contaminated with salmonella, E. coli or campylobacter, the bacteria have become so ubiquitous in the environment — especially in crowded chicken houses — that some products are bound to evade the food safety net. Once they reach a destination like a restaurant, store or home kitchen, improper handling and undercooking allow surviving germs to cause a potentially serious infection.
Thin line of protection
The nation’s first line of defense against tainted meat, poultry and eggs is the small army of 7,800 inspectors employed by the Food Safety and Inspection Service (FSIS), an agency within the United States Department of Agriculture. The inspectors work in the approximately 6,200 meat, poultry and egg production and processing plants engaged in interstate commerce in the U.S. (Peanuts and many other foods are monitored not by the FSIS, but by the Food and Drug Administration, which is part of the Department of Health and Human Services.)
FSIS inspectors provide a thin line of protection against foodborne illnesses. FSIS tries to uphold a federal mandate to have at least one inspector performing continuous inspection during every shift in a slaughter facility. In a processing facility, the FSIS requirement is to visit at least once per day.
However, because plants typically operate multiple shifts throughout the day, FSIS inspectors often can't meet the requirements. Even with a budget of $930 million, the agency is in need of more funding, said Erik Olson, director of chemical and food safety programs at the Pew Charitable Trusts.
Olson called the lack of resources for both FSIS and the FDA's food safety programs “deeply troubling.” The USDA agency acknowledges problems with both staffing and resources.
The industry, government and food safety advocates all agree that controlling salmonella in a meat or egg facility is very difficult, partly because the germ exists almost everywhere animals are raised or handled. It can live on floors, in pen litter, in trucks and in the bodies of the animals themselves. Even a perfectly clean product can be cross-contaminated by germs carried by another animal, or left on surfaces, machines, or in plant water.
In recognition that not every chicken, package of ground meat or carton of eggs can be tested by federal officials, the Department of Agriculture began a program in 1996 called Hazard Analysis and Critical Control Point (HACCP) to create systems within plants that prevent bacterial contamination rather than catching it after it occurred.
For example, after the program was implemented many poultry slaughterhouses changed equipment and made more use of chlorinated water to wash and chill chicken carcasses, explained Richard Lobb, spokesperson for the National Chicken Council.
“If you follow HACCP, if you are properly trained in how to put it together, the whole idea is that if the product goes out the door it will be safe” even if the product itself was not physically inspected, explained Ted Labuza, a professor of food science and engineering at the University of Minnesota.
Such changes do seem to have reduced the number of animal products that leave production plants carrying salmonella.
“The data shows that the number of incidents in meats has gone down dramatically,” said University of Minnesota agricultural economist Brian Buhr, an expert in livestock markets. “Some of that is attributable to the HACCP programs. It can be improved, but by and large it is viewed in the meat industry as a success story.”
So why haven’t rates of human infection dropped?
In part, because the government is now able to find episodes of disease that once went unnoticed, said CDC's Williams. In response to the 1993 E. coli outbreak, the USDA, CDC, FDA and a network of state health laboratories established two new computer network monitoring systems, FoodNet and PulseNet, to spot and identify episodes of disease as soon as they emerge. For example, each year the PulseNet computer system identifies hundreds of clusters of patients infected with salmonella, E. coli and other foodborne diseases.
But rates also remain high because, despite the significant improvements in the system, many items still leave plants carrying salmonella. “I can tell you that (in) chickens today — still — there is presence of salmonella and campylobacter in 70 percent of poultry sold in grocery stores,” Labuza said.
Lobb disputed that number, saying that about 10 percent of chickens test positive.
The truth may be somewhere in between.
As part of the HACCP regime, FSIS tests actual products and issues reports every quarter to see if processing plants are maintaining acceptable levels of salmonella contamination. In the third quarter of 2008, 40 percent of broiler chickens processed at “very small” plants tested positive for salmonella. Large plants did considerably better with 4.8 percent testing positive.
Rates in pigs and cattle (in which concern over E. coli outranks salmonella) were much lower, at 2 percent for hogs and 2.9 percent for ground beef.
In 2005, 16.3 percent of sampled broilers from all size plants tested positive for salmonella. By 2007 the number had dropped to 8.5 percent.
Protecting against poisoning
Unlike with peanuts, you can protect yourself against infection by cooking meat, poultry and eggs. Heat destroys the bacteria.
Sam Beattie, a food safety extension specialist at Iowa State University, pointed out that salmonella can be introduced to a product at any point before it reaches a fork, like a cutting table in a restaurant, or a shelf in a refrigerator, often through cross-contamination.
To make sure you don’t become sick from that bacteria, pick up meat, poultry and egg products as the last items during a trip to the store so they spend less time outside refrigeration. Use plastic bags to wrap the products so juices do not come in contact with other items in the shopping cart or your hands. Put them in the refrigerator as soon as you get home and make sure they cannot drip on other items or on shelves.
- Do not wash poultry in the sink; it just transfers germs. There is no need to wash poultry at all, Beattie said. Do not allow raw meat, poultry or egg to touch the same surface areas as other foods. Use different cutting boards, or thoroughly clean a board with hot, soapy water after cutting meat and poultry.
- Do not eat raw or runny eggs, including whites. If you like, say, egg white protein in a smoothie, use pasteurized egg whites.
- Cook poultry to 165 degrees as measured with a thermometer from the center of the bird. Cook hamburgers to 160 degrees and cuts of whole meat to between 135 and 140 degrees.
- Return leftovers to the refrigerator within two hours and consume the leftovers within the next five to seven days.
- Most importantly, wash your hands at every step in the process. “The leading cause of foodborne illness in this country is somebody forgetting to wash their hands and then getting human fecal material into food,” Beattie said. “Hand washing is a phenomenally important public health measure.” All you have to do, he said, is use warm water, soap, and wash long enough to sing one verse of “Happy Birthday.”