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Home , Foodborne illness

Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 1

MF-2269 Safety

the enormity of foodborne are across the United tiny living creatures, much States. Trends are tracked to too small to see with the Microorganisms monitor the growth or decline naked eye. In recent years, a in foodborne illness. Specific number of widely reported and locations are identi- outbreaks of foodborne and Foodborne fied to determine the propor- illness caused by micro- tion of foodborne disease to bial contamination have those foods. that increased public aware- Illness are monitored include Cam- ness and concern about the pylobacter jejuni, Cyclospora, safety of food. Crytosporidium, E. coli O157: Microorganisms are H7, monocytogenes, everywhere in nature and Revised by: , , Vib- in human environments. Fadi Aramouni, Ph.D. , Professor rio vulnificus, and Yersinia There are many beneficial Karen Blakeslee, M.S., Extension Associate enterocolitica. that give many food Institute The majority of cases of products their characteristic Original author: foodborne illnesses are not flavor and quality. Ripened Karen P. Penner, Ph.D. Professor Emeritus reported because the initial cheeses, pickles, sauerkraut, Food Science Institute symptoms of most food- and fermented borne illnesses are not severe benefit from certain lactic enough to require medical Department of Animal Sciences and Industry acid bacteria that ferments attention, the medical facility the food and produces or state does not report such an acidic flavor. A good cases, or the illness is not recognized example of adding a beneficial bacteria to the Centers for Disease Control and vention (CDC) in Atlanta, Georgia, as foodborne. It is estimated, however, is adding lactic acid to to form Pre there are an estimated 250 foodborne that millions of people become sick curds for cheese. Microorganisms need pathogens. Contamination can occur at each year from contaminated food and food, just as humans do, so they com- any point in the food chain, from farm several thousand die. In 1996, it was pete with us for our food supply. Food estimated that between 6.5 million and can supply nutrients that support their to table. According to U.S. Department of 81 million cases of foodborne illness growth. Under the right conditions, and as many as 9,100 related some of those microorganisms can estimates, the cost of medi- vity, and occur each year. cause human illness; others can cause cal treatment, lost producti costs of premature deaths for In 2004, it was reported there were the food to spoil. Spoilage bacteria, from selected bacteria may have been significant declines in foodborne illness such as mold, can cause food to deteri- as much as $6.9 billion during 2000. due to common bacterial pathogens. orate and spoil. These bacteria typically From 1996-2004, the of cause flavor changes, unpleasant odors, Because of ineffective and under-re- sourced monitoring procedures, data on E.coli O157:H7 decreased 42 percent. and texture changes. An example is actual cases and outbreaks of food- decreased moldy . Spoilage bacteria typically borne illness are inaccurate and greatly 31 percent, dropped don't cause illness but are unpleasant underrepresent the actual incidence of 40 percent and Yersinia dropped 45 to eat. In contrast, illness. percent. Overall, Salmonella infections may not cause visible changes to food; The Foodborne Diseases Active Sur- dropped 8 percent, but only one strain therefore, the consumer will not know veillance Network (FoodNet) was cre- showed a significant decline. if the bacteria is present. These bacteria ated in 1996 as the primary foodborne Bacterial pathogens are the most will be discussed in more detail. disease portion of CDC's Emerging commonly identified cause of food- Infections Program (EIP). Ten states borne illness. They are easily transmit- The Problem of Foodborne are currently part of the FoodNet ted and can multiply rapidly in food, Illnesses program including California, Colo- making them difficult to control. Foodborne illnesses generally cause rado, Connecticut, Georgia, Maryland, In 2003, CDC has targeted the fol- temporary disorders of the digestive Minnesota, New Mexico, New York, lowing foodborne diseases as report- tract; however, they can also lead to Oregon, and Tennessee. The purpose able: E. coli O157:H7, , more serious consequences. According of the program is to better determine , and Trichinellosis.

Kansas State University Agricultural Experiment Station and Cooperative Extension Service Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 2

The CDC also is concerned about with immune disorders such as HIV/ certain individuals, causing an illness other bacterial pathogens, such as Vib- AIDS—are increasing. Also, employee such as to flare up. In rio vulnificus and Yersinia enterocoliti- turnover and the need for constant other cases, no immediate symptoms ca that can cause serious illnesses, and training and supervision and other appear, but serious consequences even- perfringens and Staphylo- factors in the industry, and tually develop. About 2 to 3 percent of coccus aureus that cause less serious mishandling or improper preparation at all cases of foodborne illness lead to illnesses but are very common. any step in the food system, including serious consequences. Viral pathogens are often trans- the home, can further increase the risk. E. coli O157:H7 can cause kidney mitted by infected food handlers or In general, animal foods – beef, failure in young children and infants. through contact with sewage. Hepatitis pork, , , milk, and It is most commonly transmitted to A and Norwalk are proven to eggs – are more frequently identi- humans through eating undercooked cause foodborne illnesses. fied as the source of outbreaks in the ground beef. officials believe United States than nonanimal foods. The largest reported outbreak in that the risk of foodborne illnesses Increasingly, however, produce such as North America occurred in 1993 and is increasing. Because of our large- apples, , potatoes, , , affected more than 700 people. Fifty- scale food production and distribution sprouts, berries, melons, and tomatoes five patients, including four children system, products that may be contami- have been associated with foodborne who died, developed hemolytic uremic nated can reach a greater number of illnesses. syndrome, which is characterized by people. kidney failure. In addition, new and more virulent Not Just the Flu Salmonella can lead to reactive strains of previously identified harmful Many foodborne illnesses are brief arthritis, serious infections, and deaths. bacteria have appeared in the past sev- and cause flu-like symptoms—, In recent years, outbreaks have been eral decades. Some of these organisms , and minor aches and pains. caused by the consumption of many are resistant to usual controls such as In a small percentage of cases, more se- different foods of animal origin, includ- . rious illness and can result. Food- ing beef, poultry, eggs, milk, and dairy Furthermore, the populations of borne infections can spread through the products, and pork. “at risk” persons – the old, the very bloodstream to other organs. Complica- The largest outbreak occurred in young especially in day-care settings, tions also can result when diarrhetic the Chicago area in 1985 and involved those who have chronic illnesses, those infections act as trigger mechanisms in more than 16,000 laboratory-confirmed

Figure 1. Some Foodborne Pathogens that Can Cause Serious Illnesses. Bacteria Potential illnesses Food sources of the bacteria Campylobacter Arthritis, , Guillain-Barre syndrome Poultry, raw milk, meat, mushrooms, shellfish, clams, (paralysis); chronic ; meningitis; and inflam- eggs, water mation of the heart, gallbladder, colon, and pancreas. E. coli O157:H7 Hemolytic uremic syndrome (HUS) which is associ- Meat (especially ground beef), raw milk, alfalfa ated with kidney failure, neurologic disorders, other sprouts, apple cider, poultry, hot dogs, lettuce, dry illnesses cured salami Listeria Meningitis, blood poisoning, stillbirths, and other Soft cheese, other dairy products, meat, poultry, sea- disorders. food, , vegetables, hot dogs Salmonella Reactive arthritis, blood poisoning, Reiter’s disease Poultry, meat, eggs, dairy products, seafood, fruits, (inflammation of joints, eye membranes, and urinary vegetables, chocolate, peanuts, sauces, salad dressings, tract), and inflammation of the pancreas, spleen, colon, gallbladder, , and heart. Shigella Reiter’s disease, HUS, pneumonia, blood poisoning, Salads (potato, tuna, shrimp, macaroni, chicken), milk neurologic disorders, and inflammation of the spleen. and dairy products, and produce, poultry, water vulnificus Blood poisoning Seafood (oysters, clams, crabs) Reiter’s disease, pneumonia, and inflammation of the Meat, raw milk, oysters, fish vertebrae, lymphatic glands, , and spleen Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 3

cases and an estimated 200,000 total reported, including at least 13 cases of Figure 3. Typical Growth Curve cases. Some of these cases resulted in meningitis. At least 48 deaths, includ- reactive arthritis. One institution that ing 20 stillbirths or miscarriages, were treated 565 patients from this outbreak attributed to the outbreak. Soft cheese Resting confirmed that 13 patients developed produced in a contaminated factory en- reactive arthritis after consuming con- vironment was confirmed as the source. taminated milk. In addition, 14 deaths Campylobacter may be the most may have been associated with the common factor for Guillain-Barre outbreak. (G-B) syndrome, which is now one of Lag Death Phase Listeria can cause meningitis and the leading causes of paralysis from

stillbirths and has a fatality rate of 20 disease in the United States. Campy- Log of Numbers Bacteria deaths per 100 illnesses. The CDC re- lobacter infections occur in all age ports that the rate of listeriosis dropped groups, with the greatest incidence in If we start with the 20th genera- 35 percent from 1996 to 2002. All children under one year of age. Most tion containing 524,288 bacteria, it foods may contain these organisms, cases occur individually, primarily from takes only one generation to reach particularly raw poultry and unpasteur- poultry, not during large outbreaks. 1,000,000 bacteria, which is a large ized dairy products. It is also found in The CDC estimates 1 in every 1,000 enough population to cause spoilage to ready-to-cut meats. reported cases of Campylobacter leads begin in food products. If the equip- The largest outbreak occurred to G-B syndrome. That means about ment, personnel, and product are clean, in 1985 in Los Angeles, largely in 40 percent of G-B cases are a result of the initial numbers of bacteria will pregnant women and their fetuses. Campylobacter . be lower, and we may begin with the More than 140 cases of illness were 15th generation of 16,384. In this case, Preventing Growth will increase, and it will take Figure 2. How Microorganisms Grow of Microorganisms five times longer to reach 1,000,000 Starting with one organism. . . Microorganisms are everywhere. bacteria. Generation Number of Bacteria When fruits, vegetables, and other Figure 3 shows a typical growth 1 1 crops are harvested and when livestock curve. Four distinct phases occur in the 2 2 are slaughtered or milk is taken from growth curve: lag; log or growth phase; 3 4 cows, microorganisms are present. stationary or resting phase; and death 4 8 phase. 5 16 Further contamination occurs as food Bacteria need about four hours to 6 32 commodities move through the food 7 64 system. adapt to a new environment before they 8 128 Some of these bacteria may spoil begin rapid growth. In handling food, 9 256 food as they produce acids (souring), this means we have less than four hours 10 512 long chains of carbohydrates (slimes), to make a decision to either cool the 11 1,024 odoriferous compounds from protein food, heat it, or eat it. 12 2,048 (foul odor), and pigments (discolor- For example, when chickens arrive 13 4,096 ations); sometimes they liquefy food. at the dock of a fast food outlet, at a 14 8,192 , or at your home, you must 15 16,384 Other bacteria may cause illness if decide whether to heat and eat them, to 16 32,768 people eat food that has not been 17 65,536 handled properly. refrigerate them at a low temperature (chickens freeze at 28°F) for a short 18 131,072 Growth of Microorganisms period of time, or to wrap and freeze 19 262,144 Microorganisms grow rapidly. 20 524,288 the chicken for longer storage. If you Figure 2 shows how microorganisms 21 1,048,576 don't decide, the bacteria will enter grow by starting with a single micro- 22 2,097,152 the log phase of growth, multiplying organism: 1 becomes 2, 2 become 4, 23 4,194,304 rapidly and causing food to spoil or 4 become 8, 8 become 16, and so on. 24 8,388,608 causing an opportunity for foodborne 25 16,777,216 This is called logarithmic growth. illnesses. 26 33,554,432 The time it takes a bacterial to Spoilage bacteria produce the slime, 27 67,108,864 reproduce is called the generation time. , off-colors, and odors associated 28 134,217,728 The figure also shows how important with in the log phase of 29 268,435,456 initial numbers of bacteria are. 30 536,870,912 growth. Pathogenic bacteria can grow Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 4

and produce large numbers or toxic Food. Like all living things, bacteria Bacteria need water because their compounds and these are usually not require food to live, but they need only only means of obtaining food is by detected by off odors, flavors, etc. Re- very small quantities. Some protein absorption similar to that of a sponge. member, the four hours bacteria remain or fat left on the wall of a processing This process cannot be accomplished in the log phase is approximate and plant, grease on the blade of a knife, without moisture, which explains why cumulative. or food residues on the wheel of a foods such as dried milk, dried soups, As microorganisms grow, they tend can opener or on a cutting board are a and cereals do not spoil microbiologi- to form colonies of millions of indi- feast for microorganisms as well as for cally. The organisms are there . . . but vidual cells. Once a colony forms, the larger pests. they can't eat. food available to each cell is limited Acid/base. Every has and excretions from these millions of an optimal pH (acid) concentration for Bacterial Causes cells become toxic to a microbe. This is growth. Yeasts and molds favor more the stationary phase. Some of the cells acidic conditions than bacteria. of Foodborne Illness now begin to die. Time. Some organisms grow faster cereus If we can control bacterial growth, than others. Under ideal conditions, The disease: Two distinct syndromes we can control the major cause of food certain bacterial populations can dou- may occur. In one, the produced spoilage and foodborne illness. ble in as short as nine minutes; others results in diarrhea, and in the other, the Keeping initial bacteria levels low require hours. Bacteria that reproduce toxin causes vomiting. Generally, the is important. A food product that starts most quickly will dominate. diarrheal toxin is associated with con- with 100 microorganisms per gram Temperature. Temperature is prob- sumption of puddings, starchy sauces, may have a shelf life of 12 days before ably the single most important factor or vegetables such as mashed potatoes. it develops off odors, slime, and spoil- in preventing microbial food spoilage. The emetic syndrome is most frequent- age. When the initial number is 5,000 Generally speaking, the cooler the food ly associated with cooked rice. per gram, the shelf life of that same is kept, the longer shelf life it will have. The organism: foodstuff may be shortened to seven A in the refrigerator is forms heat-resistant spores so it can days. Because so much depends on a necessity. Maintain the temperature survive the initial of starch- the initial number of bacteria, tem- at 35° to 40°F. Remember, however, based products. The spore can then ger- peratures, and handling practices, a that some foods, such as tomatoes and minate if cooked products are not kept specific shelf life for a category of food lettuce, will freeze or be damaged at hot (140°F or higher) before serving. products is difficult to determine. 32° to 33°F. Control: Avoid holding freshly Different bacteria require different cooked, hot grain foods and vegetables A good "rule of thumb" is: temperatures for maximum growth. any longer than necessary before serv- To double the shelf life of a food Some bacteria will grow at refrigerated ing. Keep cooked foods hot to prevent that needs refrigeration, lower the temperatures. Others will only grow at spore germination or refrigerate and temperature 18° F. moderate temperatures. Warm-loving chill rapidly. Reheat previously cooked That is, for every 18° F decrease bacteria grow at temperatures above rice and vegetable dishes to 165°F prior in storage temperature, food will 140°F. They grow and reproduce at a to serving. Avoid slow cooling and last twice as long. slower rate at temperatures above and reheating. Good personal , sanitizing below the optimum. Food spoilage equipment, controlling temperature, bacteria grow best at environmental The disease: Campylobacter jejuni and using chlorinated water where temperatures of 70° to 100°F. has been recognized for years as a possible are all practices that help keep Oxygen use. Microorganisms are cause of abortion in sheep. Campylo- initial numbers low. considered aerobic if they can use bacteriosis or Campylobacter enteritis oxygen, anaerobic if they grow best in humans is now more common in the Requirements for Growth—FATTOM United States than salmonellosis. Com- Microorganisms need without oxygen, and facultative if they mon symptoms include profuse and • food to meet growth requirements, can grow well with or without oxygen. sometimes bloody diarrhea, nausea, • the right acid/base conditions, Moisture. All living things require cramps, headache, and fever. • time at conditions that allow growth, moisture, and bacteria are no excep- Onset is within two to five days after • temperatures that support growth, tion. Perishable foods requiring refrig- eration usually have very high moisture eating contaminated food. The illness • specific oxygen (or no oxygen) contents. Moist food left over for long may last two or three days, but it can requirements, and last weeks or months with complica- • moisture. periods of time provides adequate tions such as meningitis, cholecystitis, Different microorganisms require moisture for bacterial growth. urinary tract infection, and reactive different combinations of these factors. Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 5

arthritis. The CDC estimates 124 fatali- germinate, resulting in rapid growth streams, gills and viscera of fish, and ties each year. of new vegetative cells, especially in seafood. They can be found on fruits The organism: C. jejuni is found foods that have been allowed to cool and vegetables, as these items are in the intestinal tract of animals, with slowly with inadequate refrigeration. If often in contact with the soil. Spores almost 100 percent occurrence in poul- food is inadequately reheated, ingested have also been found in and try. Raw meats and poultry are impor- organisms could then cause illness. corn syrup. Meats and vegetables can tant sources along with raw milk and Control: Illness can be prevented by provide nutrients for growth and toxin untreated water supplies. The majority proper handling of foods, particularly production. of cases have occurred after consum- meats, poultry, stews, roasts, meats, Control: Conditions favoring growth ing raw milk, undercooked poultry, or pies, casseroles, and gravies. Cook and toxin production by C. botulinum raw meat. Infected cats and puppies are items and then cool them rapidly in include high-moisture, low-, low- also sources. shallow pans in the refrigerator. Avoid acid (pH greater than 4.6), low-oxygen Control: The organism requires cooling gravy, stews, or chili in deep foods such as canned or vacuum- reduced oxygen levels and can survive cooking pots. If foods are to be held packed products, and storage at room several weeks of refrigerator tempera- hot, keep the temperature above 140°F. temperature. Foods commonly involved tures. It is easily killed by heat and is Thoroughly reheat leftovers (to 165°F) include canned vegetables, fish, meats, inhibited by acid, salt, and drying. before eating. Use good personal chili sauce, chili peppers, tomato relish, To control C. jejuni, drink only hygiene. and salad dressing. pasteurized milk; avoid cross-con- The majority of outbreaks have tamination of cooked or ready-to-eat The disease: Foodborne been caused by home-processed foods. foods by utensils, equipment, or cutting results from eating food in which Other foods include foil-wrapped surfaces not properly cleaned and Clostridium botulinum has grown and baked potatoes held at warm, not hot disinfected after contact with fresh, produced neurotoxin. The toxin is temperature (above 140°F); cooked uncooked meats or poultry; and use absorbed and binds to nerve endings. It also held at warm temperatures; good personal hygiene; wash hands causes vomiting and diarrhea, fatigue, and garlic in oil mixtures stored at after handling raw meats to avoid dizziness, and headache. Later there is room temperature. transmitting organisms to other foods constipation, double vision, dry mouth, C. botulinum spores are heat-resis- and utensils. and difficulty speaking and swallowing. tant. Therefore, canned meat, poultry, Involuntary muscles become paralyzed. fish, and low-acid vegetables (i.e., corn, The disease: Ingestion of food Cardiac and respiratory failure, and , spinach, beets) require pres- containing large numbers of vegeta- ultimately, death occurs. Symptoms sure canning to achieve a high enough tive cells of Clostridium perfringens usually show within 18 to 36 hours temperature (240°-250°F) for sufficient is necessary for illness to occur. In the after eating, but could be as long as time to destroy spores. intestines, the vegetative cells can form 10 days. Today, because of rapid treat- It is important for home canners to spores and release toxins. Diarrhea and ment, botulism is fatal in fewer than use research-based, up-to-date process- severe abdominal pain are the usual 10 percent of cases. Recovery may take ing methods. Oven, microwave, and symptoms. Nausea is less frequent. years. open-kettle canning are definitely not Fever and vomiting are unusual. Death Infantile botulism, affecting infants recommended! Avoid use of home vac- is uncommon, but has occurred in under fourteen months, is another type uum packaging machines to enhance older, debilitated people. of botulism, first identified in 1976. storage of low-acid, high-moisture The organism: Spores of This disease can occur after infants refrigerated products. Store leftover C. perfringens are found in soil. The ingest bacterial spores which colonize foods and commercially vacuum organism also is part of the normal in- and produce toxin in the intestinal tract. packaged meats in the refrigerator or testinal content of animals and humans. Spores have been found in honey freezer. Avoid feeding honey and corn C. perfringens requires protein for and syrups and have been implicated syrup to infants. growth and will grow with or without in some cases of infantile botulism. O157:H7 oxygen. Spores are common in raw Other nonfood items may be sources of The disease: At least four types of foods, and they are heat-resistant. spores. Symptoms of infantile botulism Escherichia coli can cause gastroin- Cooking foods will destroy vegeta- include constipation followed by leth- testinal disease in humans. One type tive cells but not necessarily the spore argy, poor feeding, weakness, drooling, causes infantile diarrhea; another can forms of the bacteria. In addition, weak cry, and loss of head control. cause traveler's diarrhea, associated cooking drives off oxygen, kills com- The organism: C. botulinum spores with travel in foreign countries. peting organisms, and heat shocks the are widely distributed in soils, shore, Another type causes a dysentery- spores. Then, the remaining spores may and bottom deposits of lakes and like illness similar to shigellosis, and Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 6

a fourth type, O157:H7, produces been fertilized with infected sheep ma- Those at greatest risk include the very hemorrhagic colitis, a severe illness nure. Postpasteurization contamination young, the aged, and those whose characterized by bloody diarrhea and can also be a cause of outbreaks. health status is poor. severe abdominal cramps. Hemolytic The organism: L. monocytogenes is Mortality rate from enteric fever is uremic syndrome (HUS) can be a com- widely distributed in soil, vegetation, high. Salmonella typhi is the common plication in children and is a leading water, and animals. The organism can cause of enteric fever, but any of the cause of acute kidney failure. survive for long periods in soil, silage, more than 2,000 different Salmonella The organism: This organism is a feces, and milk and other dairy foods. organisms are capable of causing en- normal component of the gastroin- It grows well in sewage. Use of sewage teric fever. testinal tract. The major source of the sludge and effluent on edible crops is In addition to the acute effects of bacteria in the environment is the feces hazardous, as is the use of manure from Salmonella infection, it is now known of humans. Feces and contaminated infected livestock. that serious chronic rheumatoid or car- water are the most likely sources for Listeria is capable of growing diac problems may occur after recovery food contamination. For years, E. coli at refrigerator temperature, but it is from the acute disease. was considered harmless to health and sensitive to heat. It also tolerates high The organism: Salmonella are wide- was used as an indicator of fecal con- concentrations of salt. Because of its ly distributed in both wild and domes- tamination in food and water. wide distribution in nature, its abil- tic, warm- and cold-blooded animals. It Control: Foods that have been impli- ity to survive for long periods, and its is estimated that some 40 percent of all cated in E. coli O157:H7 outbreaks of ability to grow under refrigeration, poultry are contaminated. The disease foodborne illness include mold-ripened L. monocytogenes could be an impor- in humans reflects the close human as- cheeses, inadequately cooked ground tant cause of foodborne illness in the sociation with animals. beef, lettuce, and unpasteurized apple future, particularly as the popularity of Meat and poultry are the most im- beverages. Good sanitation practices ready-to-eat, refrigerated foods contin- portant sources of Salmonella. Because in the manufacture of products such as ues to increase. Salmonella are very heat-sensitive, they cheese, good personal hygiene when Control: To control the organism, are destroyed by normal cooking and working with food, cooking meat control its occurrence in raw food pasteurization processes. They will, thoroughly (155°F is the 2001 Food materials and follow good sanitation however, survive long periods of time Code recommendation for foodservice practices in plants. Use in dried or frozen foods. When frozen and 160°F is the FSIS recommendation pasteurized milk and avoid postpasteur- foods are thawed, these organisms can for consumers at home), and avoiding ization contamination of milk. Cook grow again. recontamination after cooking or pro- foods thoroughly. Control: In homes and foodservice cessing will control E. coli O157:H7. Salmonella sites, human salmonellosis can be The disease: Salmonellosis is the prevented by proper handling of meats, The disease: Listeria monocyto- classic example of foodborne infec- poultry, and other animal foods. Keep genes causes the disease listeriosis. tion. There are actually three types of raw foods away from cooked foods, Before the 1980s, it was associated diseases caused by Salmonella: Enteric avoiding cross-contamination. Cook with abortions and encephalitis in fever caused by S. typhosa, in which animal foods thoroughly and hold at sheep and cattle. The disease in hu- the organism, ingested with food, either cold temperatures (below 40°F) mans begins with nausea, headache, finds its way into the bloodstream and or hot (above 140°F). Avoid drinking fever, and vomiting. In severe cases, is excreted in the stools; septicemia unpasteurized milk. Thaw turkeys, meningitis, abortion, stillbirth, and caused by S. choleraesuis in which the roasts, fish, and other meats in the perinatal septicemia can occur. The organism causes blood poisoning; and refrigerator, not on the countertop. Use disease is rare in nonpregnant healthy caused by good personal hygiene practices. adults; however, adults with the follow- S. tyhimurium and S. enteritidis, a A number of recent outbreaks of sal- ing conditions are more susceptible: true foodborne infection. In this monellosis have been due to processing neoplasm, AIDS, alcoholism, type 1 case, large numbers of organisms are errors, particularly in the handling of diabetes, cardiovascular disease, renal ingested with food and cause localized milk, cheeses, and deli meats. Prob- transplant, and corticosteroid therapy. infection of the intestinal tract with no lems of this nature are controlled by The mortality rate is about 30 percent invasion of the blood stream. more attention to sanitation and quality in the unborn, newborn, or immune Symptoms of salmonellosis include control at the processing plant. compromised. Outbreaks have been nausea, vomiting, headache, chills, Shigella associated with consumption of milk, diarrhea, and fever. In most cases the The disease: Shigellosis, also known certain soft cheeses, and coleslaw made disease is short-lived and the person as bacillary dysentery, is caused by from contaminated that had recovers. It can be fatal, however. several bacteria of the genus Shigella. Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 7

Symptoms include diarrhea (often contamination. Any food that requires foods thoroughly. Then, cool foods bloody), abdominal pain, vomiting, and handling in its preparation can become in shallow containers in refrigerators. fever. Generally, foodborne shigellosis contaminated. Keep meat salads, potato salads, cream involves a short incubation time (seven The skins and hides of animals can pies, puddings, and pastries chilled un- to thirty-six hours), but symptoms per- also harbor Staphylococcus organisms til served. Avoid leaving foods at room sist three to fourteen days. As few as 10 and may contaminate foods from these temperature for more than two hours. to 100 organisms have been shown to animals at slaughter. Yersinia enterocolitica cause illness. Secondary infections oc- Foods that best support growth The disease: This bacteria causes cur frequently. Recently, shigellosis has include protein foods such as meats, yersiniosis. The most common form become a problem in day-care centers. poultry, and fish; cream sauces; salads causes various symptoms of gastro- Shigella sometimes leads to Reiters such as ham, turkey, and potato; enteritis, but more serious forms can syndrome. puddings; custards; and cream-filled lead to polyarthritis, septicemia, and The organism: Shigella organ- pastries. S. aureus bacteria are not a meningitis. Death from gastroenteritis isms are generally considered fragile. problem in raw foods because other is rare, and recovery, if there are no They are readily killed by heat used in harmless bacteria crowd them out. further complications, occurs within processing or cooking, and they do not The harmless bacteria may be de- one or two days. survive well in acidic foods (pH below stroyed in heated foods, leaving a niche The organism: Y. enterocolitica is 4.6). They can survive for extended for S. aureus should the food become commonly found in a wide variety of periods, however, in certain foods. contaminated. In addition, many of animals, food, and water sources. Pigs Most outbreaks result from con- these cooked foods are handled and are the most important animal source. tamination of raw or previously cooked prepared in final form after cooking, Food sources include raw milk, meat, foods during preparation in the home which permits the food handler to poultry, shellfish, vegetables, and tofu. or in foodservice settings. Often, the contaminate foods whose harmless Certain strains of the bacteria pro- source of the contamination is traced to bacteria have already been destroyed. duce disease, but it appears that many a carrier with poor personal hygiene. In In mayonnaise-type salads (ham, of the strains are nonpathogenic. Y. fact, the “4 Fs” involved in the trans- egg, etc.), the acidity of the mayonnaise enterocolitica can grow at refrigerator mission of Shigella are food, finger, inhibits the growth of Staphylcocci. But temperatures, but grows best at room feces, and flies. because other low-acid ingredients are temperature. It is sensitive to heat and Control: Infected food handlers are mixed with the mayonnaise, the acid is destroyed by adequate cooking and the most likely source of contamination level may be diluted sufficiently to sup- by pasteurization of milk. of food by Shigella, so good personal port growth of S. aureus. Salt and Control: Postpasteurization contam- hygiene is necessary to control the or- added to certain food systems also ination is the most frequent cause of ganism. Other control measures include inhibit growth of other organisms, but foodborne outbreaks. Thus, preventive use of properly treated water, sanitary do not inhibit S. aureus. The microor- measures in processing plants need to disposal of sewage, and control of flies ganism grows well at body temperature include strict adherence to procedures and rodents. but can grow at both colder and hotter for keeping perishable products, such temperatures. as tofu and milk, clean and cold. The disease: Staphylococcus organ- Heat processing and normal cooking Vibrio isms are capable of producing very will kill S. aureus organisms, but heat- Three Vibrio species are considered heat-resistant . The toxins, ing does not destroy the . separately because each is responsible rather than the actual bacteria, are re- Control: Because S. aureus bacteria for a different disease syndrome, and sponsible for causing foodborne illness. are common and widespread in their modes of causing foodborne ill- Common symptoms include nausea, humans, preventing contamination ness also differ. CDC estimates 8,000 vomiting, cramps, sweating, chills, of food is virtually impossible. cases each year. Contaminated food must be held at weak pulse, shock, and lowered body a warm temperature for a sufficient temperature. Recovery usually occurs The disease: causes thou- time to permit enough bacteria to grow within two days. sands of deaths each year, primarily in and produce a level of enterotoxin to The organism: S. aureus is found in Asian countries. Since 1978, however, make someone sick. Thus, temperature the nose and throat and on the hair and there have been numerous reports of control is one of the most effective skin of more than half of the healthy human illness in the United States, ways to control staphylococcal population. Infected wounds, lesions, most of which have been traced to intoxication. , and mucous spread by coughs consumption of raw oysters and clams. It is important to use good hygiene and sneezes of people with respiratory Vibrio cholerae colonizes the small to help prevent contamination. Cook infection are other sources of intestine and causes large volumes of Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 8

fluid to be secreted. Diarrhea results in Vibrio vulnificus people in four states were infected with loss of body fluids and accompanying The disease: This Vibrio causes two . minerals. clinical forms of illness, one affecting Person-to-person , as In severe cases, cardiovascular the blood (septicemia) and the other well as foodborne and waterborne collapse and death may occur in a causing seawater-associated wound transmission, occur. Adults are more day’s time. Organisms are excreted in infections (progressive cellulitis). The susceptible to this illness. Foods large numbers and can be transmitted death rate is 50 percent for those with become contaminated by food han- through contaminated water supplies septicemia and 22 percent for those dlers who do not follow good personal and by foods obtained from those wa- with wound infections. hygiene practices or by contaminated ters, particularly seafood. The organism: V. vulnificus is com- water. The organism: Humans are the only mon in marine environments and has Cold cuts, sandwiches, salads, natural sources of this organism. The been found in water, sediment, plank- fruits, shellfish, and iced drinks are organism is most commonly spread ton, oysters, and clams. It is heat-sensi- commonly implicated in outbreaks. through water. V. cholerae does not tive and grows best in warm tempera- Contamination of foods by infected multiply in water but can survive for up tures. Cooking destroys it. workers in food processing plants and to two weeks. It is salt-tolerant, heat- Control: Refrigeration and cooking is common. sensitive, and destroyed by cooking. of shellfish are important control mea- The organism: The Hepatitis A Control: V. cholerae is controlled by sures. In addition, avoid contaminating is made of a single molecule of RNA the use of clean water and by thorough- existing cuts or causing new wounds surrounded by a small protein capsid. ly cooking seafood. to hands while cleaning and harvesting Control: Wash hands thoroughly shellfish. after using the restroom or diapering The disease: Vibrio parahaemo- Viruses infants. Also, harvest shellfish from lyticus causes an illness characterized Viruses are submicroscopic agents unpolluted waters. by severe abdominal pain, nausea, that cause a wide range of disease in Norwalk virus diarrhea, and vomiting. It is the most both plants and animals. Because they The disease: Norwalk virus is a common foodborne illness in Asia. are not complete cells, they are not more recently discovered foodborne The largest outbreak of V. parahae- capable of growing and multiplying virus. The illness it produces is mild molyticus was in 1997 in raw oysters like bacteria. and characterized by nausea, vomiting, harvested in California, Oregon, and Viruses that infect the gastrointesti- diarrhea, and abdominal pain. Head- Washington. As a result, 209 illnesses nal tract are usually transmitted by food ache and low-grade fever may result. occurred and one person died. or water. Infection results from: Water is the most common source of The organism: V. parahaemolyticus • consumption of food contaminated by outbreaks. Shellfish and salad ingredi- has been found in warm coastal waters a food handler carrying the virus ents are the foods most often implicat- of countries throughout the world. • consumption of raw seafood taken ed. This virus is very contagious. Most disease outbreaks occur during from waters polluted by human Control: Use good personal hygiene warm seasons. wastes and avoid handling food when ill. Growth of organisms occurs while • drinking polluted water Foodborne parasites seafood are being held for consump- Hepatitis A virus Parasites found in foods or water are tion. It does not grow under refrig- The disease: Hepatitis A is usually a divided into three categories: , eration. The organism is salt-tolerant, mild illness with symptoms of sudden flatworms, and roundworms. They but it is very sensitive to heat and is onset of fever, nausea, loss of appe- grow in living hosts such as animals destroyed by cooking. tite, and abdominal discomfort, and is and are larger in size than bacteria. Control: Refrigeration and proper followed by . The incubation Parasites can transfer from animals to cooking are important means of con- time may be 10 to 50 days. During the humans, humans to humans, or humans trolling V. parahaemolyticus. Consump- middle of the , it can to animals. The primary source for tion of raw fish and shellfish poses be transmitted to others. Usually, recov- parasites is feces. Fish are also carriers risks. After cooking, it is important to ery is complete in one to two weeks. of parasites. Cooking or freezing fish avoid cross-contamination between The CDC recorded 25,000 cases per will kill the parasites. raw and cooked seafood. In the United year of Hepatitis A from 1980 to 2001. Cryptosporidium parvum States, this has been the most frequent Adjusting for underreporting reveals an The disease: Crytosporidiosis is a cause of V. parahaemolyticus infec- estimated 263,000 per year. One of the significant cause of waterborne illness. tion. In Japan, however, the illness largest Hepatitis A outbreaks occurred The disease occurs by consuming frequently involves consumption of raw in 2003, which involved green onions contamiated water or from putting any- seafood. imported from Mexico. More than 700 Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 9

thing in your mouth that touched feces Bacterial resistance to antibiot- Centers for Disease Control and Prevention. containing Crytosporidiosis. Symptoms ics has increased in the last 10 years. “Surveillance for foodborne-disease occur 2 to 10 days after ingestion. Each time a person takes , outbreaks—United States, 1988-1992.” Symptoms include diarrhea, cramps, sensitive bacteria are killed, but resis- MMWR, 45(SS-5), October 25, 1996. "Economics of Foodborne Disease: nausea, and fever. tant bacteria can multiply. Misuse of Feature" Economic Research Service, The organism: C. parvum is found antibiotics compromises the usefulness USDA. www.ers.usda.gov/brief- in the intestines of herd animals such of essential drugs. To reduce antimicro- ing/FoodborneDisease/features.htm. as cows, sheep, goats, deer, and elk. bial resistance, always follow doctor's Accessed August 31, 2005. Control: Use proper handwash- prescription instructions. Do not take Economics of Foodborne Disease: Foods ing procedures before handling foods someone else's . Discard any and Pathogens, USDA Economic and eating. Drink water only from leftover once you've com- Research Service. www.ers.usda.gov/ treated water supplies. Do not swallow pleted treatment. briefing/foodborneDisease/foodandpatho- swimming pool water. When hiking, gens. Accessed August 31, 2005. "Foodborne Illnesses Continue Downward camping, or in foreign countries, For more information Trend: 2010 Health Goals for E. coli water for one minute or drink bottled Centers for Disease Control and Prevention O157:H7 Reached." USDA beverages. Wash, peel, or cook raw www.cdc.gov and Inspection Service. www.fsis.usda. fruits and vegetables. CDC / Resistance. gov/news_&_Events/NR_041405_021/ www.cdc.gov/drugresistance. Accessed index.asp. Accessed December 2, 2005. December 12, 2005. The disease: is a Fung, D.Y.C. “Foodborne diseases.” In FDA Center for Food Safety and Applied Encyclopedia of Food Science and Tech- waterborne illness. The disease occurs Nutrition www.cfsan.fda.gov by consuming contaminated water or nology. Y.H. Hui, ed. New York: John FDA Center for Drug Evaluation and Wiley and Sons, Inc., 1992. from putting anything in your mouth Research: . Jay, J.M. Modern . New that touched feces containing cyclospo- www.fda.gov/cder/drug/antimicrobial/ York: Van Nostrand Reinhold, 1992. riasis. Symptoms appear one week after default.htm Penner, Karen P. Microorganisms and Food. ingesting. Symptoms include diarrhea, FightBac! NCR Extension Publication 447. Man- cramps, nausea, vomiting, muscle www.fightbac.org hattan, Kansas: Kansas State University aches, low-grade fever, and fatigue. FoodNet Cooperative Extension Service, 1992. www.cdc.gov/foodnet/ The organism: Cyclosporiasis is “Food safety: information on foodborne K-State Research and Extension Antimi- illnesses.” Report to Congressional a relatively new parasite. The first crobial Resistance and the Food Supply, reported case was in 1979. Since then, Committees, U.S. General Accounting MF-2593 at www.oznet.ksu.edu/library/ Office. GAO/RCED 96-96, May 1996. more cases have been reported. It is fntr2/mf2593.pdf. “Food safety: reducing the threat of food- unlikely passed from human to human, K-State Research and Extension Food Safety borne illnesses.” Report to Congressio- and not known if passed from animal www.oznet.ksu.edu/foodsafety nal Committees, U.S. General Account- to human. United States Department of Agriculture, ing Office. GAO/T-RCED-96-185, May Control: Use proper handwash- www.usda.gov 23, 1996. ing procedures before handling foods USDA Food Safety and Inspection Service, "Parasites and Foodborne Illness" USDA and eating. Drink water only from www.fsis.usda.gov Food Safety and Inspection Service, U.S. Government Food Safety Gateway, treated water supplies. Do not swallow www.fsis.usda.gov/oa/pubs/parasite.htm, www.foodsafety.gov swimming pool water. When hiking, accessed December 2, 2005. Summary of Notifiable Diseases – United camping, or in foreign countries, boil States. 2003. Centers for Disease water for one minute or drink bottled References Archer, D.L., and J.E. Kvenberg. “Incidence Control and Prevention. www.cdc.gov/ beverages. Wash, peel, or cook raw and cost of foodborne diarrheal disease mmwr/preview/mmwrhtml/mm525al. fruits and vegetables. in the United States.” J. of Food Protect., htm. Accessed August 31, 2005. Antimicrobial Resistance 1985, 48(10):887-894. Trends in Sporadic Vibrio Infections in This is the ability for some organ- Archer, D. L. “The true impact of food- Foodborne Diseases Active Surveillance isms to resist or fight medicines that borne infections.” Food Tech., 1988, Network (FoodNet) Sites, 1996-2002 www.cdc.gov/foodnet/pub/iceid/ should inhibit or kill the organisms. 43(7):53 58. Centers for Disease Control and Preven- voetsch_vibrioICEID2004.pdf Accessed This becomes a food-safety issue September 1, 2005. because some species of Salmonella tion. Mortality and Morbidity Weekly Report, June 12, 1998/Vol.47/No. 22 and Campylobacter have become re- www.cdc.gov/foodnet/pub/publica- sistant to antimicrobial medicines. This tions/1998/vibrio_mmwr1998.pdf has resulted in more cases of foodborne illness. Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 10 Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 11 Outdated Publication, for historical use. CAUTION: Recommendations in this publication may be obsolete. 12

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Publications from Kansas State University are available on the World Wide Web at: http://www.oznet.ksu.edu Contents of this publication may be freely reproduced for educational purposes. All other rights reserved. In each case, credit Fadi Aramouni, Karen Blakeslee, and Karen P. Penner, et al. Microorganisms and Foodborne Illness, Kansas State University, January 2006.

Kansas State University Agricultural Experiment Station and Cooperative Extension Service MF-2269 Revised January 2006 K-State Research and Extension is an equal opportunity provider and employer. Issued in furtherance of Cooperative Extension Work, Acts of May 8 and June 30, 1914, as amended. Kansas State University, County Extension Councils, Extension Districts, and United States Department of Agriculture Cooperating, Fred A. Cholick, Director.