Food, Sex and Salmonella. David Waltner-Toews
is not contaminated, then your hands, or the knives, are. (What do you do about that itch on your scalp just before you handle the dinner? Just a little scratch won’t hurt, will it?) It is best, from a bacterial point of view, if you let the meat sit on the counter for a while, just to incubate.
Salmonella get turned on by that sort of warm, moist situation. They tumble over themselves in incestuous delight, doubling their populations every half hour or so. Other bacteria are even speedier. E. coli, a common gut bacterium, doubles every fifteen to twenty minutes, and Clostridium perfringens, which tends to favor meaty gravies and causes a passing diarrhea, is a copulatory sprinter at an eight. to ten-minute doubling time. I am told by a microbiologist colleague that, with unlimited food and ideal warmth, one cell could multiply to a colony of clones four thousand times the mass of the earth in twenty-four hours. Fortunately, the cells run out of food before they reach that size.
If poultry are a haven for Salmonella, hamburgers are heaven for a veritable menagerie of bacteria. Bacteria generally sit on the surface of meat, which includes the turkey’s armpits but not the heart of a steak. When we make hamburger, we take the surface bacteria and integrate them into the larger community of meat. Hamburgers, then, are really just cases of diarrhea and vomiting waiting for stomachs to happen, unless you cook them, and cook them well. Some of America’s finest foodborne disease outbreaks have been tracked back to hamburgers.
Like most of us, Salmonella prefer temperatures that are warm but not hot and will survive freezing but not boiling. They abhor the caustic wit of bleach and the acidic tongue of tomato juice, but they are adaptable enough to make a go of it in the most soiled of environments.
Hopelessness in the face of universal pollution is sometimes used as an argument by polluters to continue polluting; in the case of antibiotic resistance in bacteria, however, the situation is not at all hopeless. Bacteria can change rapidly; the same characteristics that allow them to develop antimicrobial resistance will also lead them to drop much of that resistance. Not burdened with rules of socially acceptable reproductive behavior, they can evolve and adapt as quickly to a drug-free life as they have to drugs. If Solomon had advised us to go to the bacteria, where quick, guiltless, cooperative change is the watchword, instead of to the ants, where regimented war prevails, who knows what the shape of human civilization might be today? The short of it is: things will get better if we change our ways.
Countries such as Sweden and Denmark have been systematic and aggressive in addressing Salmonella problems. Through a mixture of legal requirements and commercial inducements, Salmonella has been reduced and all but eradicated on farms, at slaughterhouses, and in the human population in these countries. So improvements are possible, but they are going to take some realistic, complex, systems thinking, firm commitments, and perhaps some deep cultural changes. For some of us, becoming more Swedish would, after all, not be so bad.
4 COWS, CATS, AND PURE COUNTRY WATER
E. COLI AND OTHER WATERBORNE BACTERIAL INFECTIONS
DRINKING BOTTLED water every day is like using a toilet bowl brush to clean your teeth, driving a snowmobile for recreation, or using an all-terrain vehicle in the city. All these items have important uses, but in most parts of the world none of them should be part of everyday life. When they are used outside of the circumstance for which they are designed, they are, for the most part, destructive and dysfunctional. Bottled water is for emergencies and should be saved for them.
Mostly, I dislike bottled water because it represents an unwarranted and pervasive anxiety in Western societies. Bottled water purports to solve an individual problem—fear of illness—by contributing unnecessarily to big public health problems—large-scale water and energy shortages and under-funded public water systems. I hate the idea that someone can suck an increasingly scarce public good out of the ground and then use scarce energy resources to package it and sell it back to the public. This process fosters an obsession with personal health, even as it puts the health of our children in jeopardy by undermining the health of the ecosystems that provide the basis for all life. The money spent on bottled water would be better spent on improving public water systems.
Bottled water may or may not be safer than tap water. The jury is out on that. Because any disease outbreaks caused by bottled water would be widely dispersed and not likely linked by individuals or physicians to that plastic-wrapped water on the counter, they would not very likely be identified. Because most people see bottled water as a solution rather than a problem, there’s not much in the literature. In 1993, two babies were brought into a Wisconsin hospital having seizures; the seizures were caused by intoxication with low-sodium bottled water, the mother having apparently thought that bottled water was better for her babies than tap water. In 2000, the Centers for Disease Control and Prevention reported that it had detected a ten-state bottled-water-associated outbreak of salmonellosis through a special pattern-recognition program called the Salmonella Outbreak Detection Algorithm, or SODA for short. A report in the journal Emerging Infectious Diseases identified bottled water as one of the risk factors for Campylobacter infection in the United Kingdom.
I am not a fanatic about bottled water. It obviously makes sense in natural disasters, such as the sudden floods in Vancouver (probably related to global warming) in the fall of 2006. I used to carry water bottles onto airplanes, where the air is very dry, but since August 2006, this has become impossible. I don’t mind, as long as water is readily available on the plane. I occasionally carry bottled water in the car or on hikes. If I have bought a bottle of water, I always refill it from the tap, a practice that bottled water companies warn me against, as they suggest it might lead to contamination.
I often drink bottled carbonated water in parts of Africa, Asia, and Latin America, where public funding for clean water has been scarce (usually as the result of development or financial or trade programs instigated by financial institutions based in North America or Europe). I drink the carbonated stuff because the nonbubbly bottled water, in whatever country you live, is often no better than the water out of the tap. In most countries, however, including nominally Muslim countries, I prefer the beer (which I know uses a lot of water).
The bottled water industry thrives on a public fear of contaminated water, and I really don’t like any industry that thrives on fear, especially fear that I have contributed to, which, by teaching about food. and waterborne diseases, I probably have. If this chapter on waterborne disease drives you to drink bottled water rather than to advocate for better public water systems, then I have failed.
So let me start by confronting the fear.
In May 2000, the small rural town of Walkerton, Ontario (population about 5,000), hit the international headlines. I remember the day, because a friend called me into the common room at the Makerere University Guest House in Kampala, Uganda, to tell me that Canada was in the news. People were dying from drinking tap water.
It started with a few reports of cases of bloody diarrhea in nursing homes and schools and ended with more than 2,300 people sick. Twenty-seven people had to be hospitalized with hemolytic uremic syndrome, a rare disease involving the breakdown of red blood cells, blood in the urine, and kidney failure. At least six people died. Some of my best friends and colleagues (veterinarians and graduates of our epidemiology program at Guelph) led the public health investigations, so I got a variety of inside and outside stories. The outbreak led to one of the most thorough inquiries into a public health disaster in Canadian history.
The drinking water for a large part of the town had been contaminated with two organisms: vero-toxin producing E. coli, or VTEC (pronounced vee-tek) for short, and Campylobacter. The most common type of VTEC is also called O157:H7, the O referring to some proteins on the surface of its body, and the H to proteins on its tail. Other E. coli’s produce the same kind of toxin, but O157:H7 is the most famous. The toxin, also called shiga-toxin because it is the same one produced by Shigella, which causes bloody dysentery in travelers and people who live in poor neighborhoods, kills kidney cells from