Exactly what are food-borne illnesses?
More than 200 distinct pathologic conditions can be included under this heading. This excludes individual allergic reactions to food, and other individual conditions with an inherited condition such a celiac disease (where wheat, rye, and barley must be avoided), or phenylketonuria. The numbers of serotypes is far greater. Salmonella enteric alone has more than 2,000 serotypes.
Foodborne illnesses can be initially divided into:
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bacterial infections such as salmonellosis or campylobacteriosis,
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viral infections such as with norovirus, or hepatitis A
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parasitic infections, such as from Trichinella or Toxoplasma
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bacterial toxins such as from Bacillus cereus or Staphylococcus aureus
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fungal toxins such as aflatoxin or patulin
Each has its distinctive route of entry through food, pathology, signs and symptoms, target tissues, control measures, treatments, onset time, infectivity potential, diagnostic and laboratory tests, and potential for complications/sequalae, and even death.
The onset time can vary from minutes (for B. cereus -emetic type- toxicosis) to days, or weeks (for hepatitis A viral infection an average 30 days onset time, or listeriosis which can extend from 15 to 40 days onset time.) Frequently someone with a foodborne illness will be convinced that the last food they ate was the cause. You MAY be correct, but don't count on it simply because you recognize the last meal in your emesis (vomit). Salmonella bacteria, for example usually affects you (vomiting and diarrhoea) between 24 and 36 hours after eating, - enough time to have had 2 or 3 meals before the symptoms began!
Many are barely noticeable, mild, and self-limiting, whereas others can have a high risk of death to the infants or elderly (e.g., listeriosis, salmonellosis, shigellosis), or if the correct anti-toxin cannot be administered in time (botulism). Although diarrhoea and vomiting are commonly associated with foodborne illnesses, some of these can can cause constipation (typhoid fever), haemorrhagic diarrhoea (Campylobacter), arthritis (Salmonella bacteremia), headache (especially the viruses), double vision and paralysis (botulism), and permanent kidney damage (enterohaemorrhagic Shiga-toxin producing E. coli)
QUESTION: How can I deliberately give myself a food-borne illness?
(I was recently asked this question, although I cannot imagine why any sane person would need to carry out this mission!).
Believe it or not, scientists have in the past voluntarily acquired foodborne diseases to study the process. (At least they had a reason.)
For you, the method is simple. Just do what thousands of food handlers in restaurants and home kitchens do every month that results in their customers, patrons, or family members developing symptoms and suffering unpleasant illness. Here are six assorted choices:
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1. Allow a little bloody "drippage" from raw poultry to fall into the bowl of potato salad in the 'fridge, and next day let the potato salad sit around for a few hours at room temperature. (Good chance of Salmonellosis, or even Campylobacteriosis - that's the one with the bloody diarrhea)
2. Pick your nose and sneeze while slicing some ham, then keep the ham at room temperature overnight. (Excellent chance of Staphylococcal toxicosis: cramps and vomiting)
3. UNDERcook your hamburger patty just to "rare" and eat several just to make sure! (Result: enterohemorrhagic E. coli infection; and you might hit the jackpot with hemolytic uremic syndrome thrown in for the lucky 15%. This is exactly what happened at a major hamburger chain in 1981)
4. Buy lots of "organically-grown" spinach, but don't bother too much with washing it before eating it raw in a salad, and sprinkle some raw bean sprouts on the top. (More E.coli, anyone?)
5. Find a local purveyor of unpasteurized milk and drink some each day (good chance of an enteric upset - (E. coli, Brucellosis, Salmonellosis, Campylobacteriosis, or many others)
6. Find someone who has hepatitis A virus infection and ask him to prepare your sandwiches for a week, and tell him its ok NOT to wash his hands after using the washroom. (Then buy extra toilet paper, and set your watch for 25-35 days time!)
7. Keep buying and swallowing those raw oysters. The incidence of illness by Vibrio parahaemolyticus and Norovirus (both foodborne infections) has been increasing in recent years.
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I could add another 30 or 40 more. These are NOT far-fetched disgusting fictional scenarios; - they are very REAL disgusting scenarios that are played out every day across the country and around the globe in hotels, hamburger joints, and family restaurants. Good luck- oh and check your health plan and life insurance first
QUESTION: What exactly is E. coli and where does it come from?
Escherichia coli is a vast family of bacteria, most of which are harmless and contribute to your healthy microbial population. For decades they were useful a "indicator organisms", revealing when fecal contamination (by animals or human) had taken place in well water for example. Then toward the end of the 1970s we began to find more dangerous strains that were capable of causing gastrointestinal illness, and in a percentage of cases (especially among children), a complication called haemolytic uremic syndrome (HUS), which results in kidney damage, often permanent.
The original type is O157:H7, sometimes called a "Shiga-toxin" E. coli, ("STEC") but since then, several other dangerous strains have been isolated and studies.
The source is a "carrier" animal - often bovine - and if we look hard enough, we usually find cattle at the source of the outbreak. This can be:
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Beef itself, contaminated from feces, mud in the slaughterhouse, and not properly cooked, for example, undercooked "rare" hamburger patties. (ALWAYS have burgers cooked to at least 72 C or 162 F )
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Vegetables (e.g. lettuce) grown near cattle or irrigated with water contaminated by cattle feces,
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Drinking water that had contained animal run-off, and not properly chlorinated.
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Unpasteurized milk frequently carries E. coli from the milking process, and almost all milk-borne E. coli infections are commonly raced to drinking raw milk.
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Apple juice, has proved an interesting vehicle, not apparently connected to cattle, except that a couple of large outbreaks have been traced to windfall apples contaminated on the ground by cattle which are allowed to wander through the orchard. The juice is then sold without being pasteurized.
Prevention: Fortunately, this bacterium does not produce toxins in the food, and is easily destroyed above 72 degrees C (162 F), so cooking foods above those temperatures will keep them safe. Solid pieces of meat are safe as long as all sides are seared at high temperature; the centre can be rare and safe, provided it hasn't been "tenderized" by having needle probes push bacteria into the middle of the meat!
Air Travel, Accidental Food Poisoning, Public Health and Safety, Emergencies, Airplane Meals, Foodborne Illnesses,
Timothy Sly. Public health epidemiologist, Toronto
A: It has happened. Perhaps the most famous case was in February, 1975, a JAL flight stopped at Anchorage (en route from Tokyo to Copenhagen and Paris) to take on fuel and food. Breakfast was served after take off, but the ham omelet had been prepared by a cook with an infected cut on the hand. Time and temperatures had allowed Staphylococcus aureus from the infected cut to produce sufficient toxin to cause illness. The result was cramps, nausea and vomiting among 196 out of 343 passengers and crew. Onset time for S. aureus is between 30 minutes to 5 hrs, well within the total flying time. Of the ill passengers, 143 were ill enough to be hospitalized when the plane reached Copenhagen.
The head of the catering facility in Anchorage for Japan Airlines reportedly committed suicide shortly afterwards (the only fatality associated with the outbreak). Fortunately, the pilots did not eat the omelet but the incident prompted a policy, adopted by most airlines, that the two pilots should eat different foods. It was also instrumental in insisting that finger dressings for food workers had to be 100% waterproof and brightly coloured for visibility, and tightened requirements for time/temperature control for foods. (Note that this is one of the toxins that cannot be destroyed by re-heating the food).
Q: How do vegetables and fruits become contaminated with E. coli?
Timothy Sly, Food-borne diseases epidemiologist
A: The vast majority of Escherichia coli strains are non-pathogenic. These "fecal coliforms" are normally found in the intestines of animals (including humans), and were generally used as "indicator organisms" to show where contamination might have taken place. Beginning in the late 1970s, several unusual strains of E. coli had been found associated with gastroenteritis. The first of these was found to produce a Shiga toxin, and classified as O157H7. It causes diarrhoea, fever, and bloody stool, and followed in 4–13% of cases (especially in children) by a complication called hemolytic uremic syndrome (HUS) resulting in severe kidney damage.
Upstream from an outbreak of enterohemorrhagic E. coli infection you will usually find animal waste, most commonly bovine. The infection can arrive directly (from the meat) or indirectly via something contaminated by animal intestinal contents.
Meats are frequently contaminated during slaughter and dressing of the carcass, and all raw meats are assumed to carry a lot of "spoilage" organisms (that cause decay but are not associated with illness), and some pathogens (disease-producers), including E. coli, Salmonella, Yersinia, Listeria, and others. Under-cooked hamburgers and other beef meats are clearly contaminated during slaughter and dressing.
Fruits and vegetables are less obvious. Apple cider sold at the farm gate was the cause in an outbreak in Ontario. The apples collected for the juice had included those collected from the ground, and these had been contaminated by cows from a neighbouring dairy farm which were allowed to wander between the apple trees. Lettuce, beans sprouts, green onions, and other salad ingredients have been grown in or on soil containing animal manure as fertilizer, and have caused several outbreaks. Raw cookie dough containing E. coli strains probably had been present on the wheat, contaminated with powdered soil.
Q: Why is it risky not to clean the entire BBQ grill regularly?
Timothy Sly. Food-borne diseases epidemiologist
A: As much as we enjoy the taste of flame-broiled meats, we should acknowledge that we are playing with fire (figuratively and literally). As meat juices and fats fall into the hot zone and become burnt/vapourized (pyrolysis), many products of the combustion include phenols, aldehydes, and polycyclic aromatic hydrocarbons, some of which are active carcinogens. (Benzo-a- pyrene is one). These rise and are deposited on the meat (the blackened, charred surfaces). They also build up on the grill itself, so a uncleaned grill will carry an accumulation of these carcinogens.
Keeping the grill surface clean reduces some of the risk.
