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1 INTRODUCTION TO FOODBORNE PATHOGENS 1120 Steven C Seideman, PhD Extension Food Processing Specialist Cooperative Extension Service University of Arkansas.

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Presentation on theme: "1 INTRODUCTION TO FOODBORNE PATHOGENS 1120 Steven C Seideman, PhD Extension Food Processing Specialist Cooperative Extension Service University of Arkansas."— Presentation transcript:

1 1 INTRODUCTION TO FOODBORNE PATHOGENS 1120 Steven C Seideman, PhD Extension Food Processing Specialist Cooperative Extension Service University of Arkansas

2 2 OBJECTIVES Discuss importance of foodborne pathogens. Discuss importance of foodborne pathogens. Discuss the classes of foodborne pathogens. Discuss the classes of foodborne pathogens. Discuss methods of controlling foodborne pathogens. Discuss methods of controlling foodborne pathogens.

3 3 Basic Microbiology Microbiology is the study of small ( micro), biological organisms, hence the word “MicroBiology” Microbiology is the study of small ( micro), biological organisms, hence the word “MicroBiology” This module is extremely basic and is not intended to make the reader an expert but will make one aware of the subject. This module is extremely basic and is not intended to make the reader an expert but will make one aware of the subject. This module only discusses foodborne pathogens. Spoilage bacteria are discussed elsewhere in the series. This module only discusses foodborne pathogens. Spoilage bacteria are discussed elsewhere in the series.

4 4 Photo courtesy USDA

5 5 OUR FOOD SUPPLY Although it may appear from the following information that there are numerous microorganisms that may be in foods, in actuality, our food supply is safer than any other country in the world and safer than any other time in the history of mankind. Although it may appear from the following information that there are numerous microorganisms that may be in foods, in actuality, our food supply is safer than any other country in the world and safer than any other time in the history of mankind. The number of cases of foodborne illnesses caused by pathogens can be drastically reduced through the use of certain food handling practices. The number of cases of foodborne illnesses caused by pathogens can be drastically reduced through the use of certain food handling practices.

6 6 Photo courtesy of USDA

7 7 IMPORTANCE The estimated illnesses from foodborne pathogens is range from 6 million to 81 million people per year. Keep in mind that there are about 286 million people in the U.S. The estimated illnesses from foodborne pathogens is range from 6 million to 81 million people per year. Keep in mind that there are about 286 million people in the U.S. The estimated annual medical costs, productivity losses and costs of premature deaths due to the 5 major foodborne illnesses is estimated at $6.9 billion (Crutchfield & Roberts, 2000). The estimated annual medical costs, productivity losses and costs of premature deaths due to the 5 major foodborne illnesses is estimated at $6.9 billion (Crutchfield & Roberts, 2000).

8 8 Pathogen Illnesses per Year Bacteria = 4,420,000 Bacteria = 4,420,000 Parasites = 1,270,658 Parasites = 1,270,658 Viral = 9,278,500 Viral = 9,278,500 The total number of illnesses from foodborne pathogens per year range from 6 to 81 million. It is hard to get an accurate number since most cases are not reported and many are never diagnosed. The total number of illnesses from foodborne pathogens per year range from 6 to 81 million. It is hard to get an accurate number since most cases are not reported and many are never diagnosed.

9 9 IMPORTANCE The CDC estimates that 78% of pathogen outbreaks occur as a result of poor food handling practices in commercial and institutional establishments while only 22% occur due to food handling practices in private residences. (Olsen et al 2000). The CDC estimates that 78% of pathogen outbreaks occur as a result of poor food handling practices in commercial and institutional establishments while only 22% occur due to food handling practices in private residences. (Olsen et al 2000).

10 10 CLASSES OF PATHOGENS Bacteria Bacteria Molds Molds Yeast Yeast Parasites Parasites Viruses Viruses Mad Cow Mad Cow

11 11 Most Common Bacterial Pathogens Bacteria #cases per year Campylobacter spp 1,963,200 Salmonella 1,257,125 Clostridium perfringens 248,000 Staphylococcus 185,000 E Coli (non-0157H7) 120,000 Shigella 89,800 Yersinia enterocolitica 86,400 Streptococcus 51,000

12 12 Most Common Bacterial Pathogens-Continued Bacteria #cases per year E. Coli 0157;H7 62,475 Bacillus cereus 27,000 Vibrio spp 4,000 Listeria monocytogenes 2,500 Clostridium botulinum 58

13 13 Most Common Parasitic Pathogens Parasite #cases/year Giardia lamblia 200,000 Toxoplasma gondi 112,000 Cryptosporidium parvum 30,000 Cyclospora cayetanensis 14,637 Trichinella spiralis 52

14 14 Most Common Foodborne Viruses Virus #cases per year Norwalk-like viruses 9,200,000 Rotovirus 39,000 Astrovirus 39,000 Hepatitis A 4,150

15 15 The Percentage of Deaths from Foodborne Pathogens Pathogen PathogenBacteriaParasitesViruses % Deaths 72% 21% 7%

16 16 The 5 Specific Pathogens that Account for 98% of Estimated Deaths Pathogen PathogenSalmonellaListeriaToxoplasma Norwalk-like viruses Campylobacter E.Coli 0157;H7 % Deaths 31% 28% 21% 7% 5% 3%

17 17 UPDATE After looking at the numbers, it would appear that viruses are a major problem but one has to remember that it is very hard to get an accurately identified source when working with viruses. Many viruses cannot live outside a host animal and are hard to count. In addition, the vast majority of cases are due to Norwalk-like viruses. After looking at the numbers, it would appear that viruses are a major problem but one has to remember that it is very hard to get an accurately identified source when working with viruses. Many viruses cannot live outside a host animal and are hard to count. In addition, the vast majority of cases are due to Norwalk-like viruses. Parasites do not represent a major category of foodborne illness. Parasites do not represent a major category of foodborne illness. Bacteria are the single largest concern for food processors. Bacteria are the single largest concern for food processors.

18 18 Bacteria Bacteria are single celled organisms which takes nutrients through its cell wall. Bacteria are single celled organisms which takes nutrients through its cell wall. Bacteria are responsible by the vast majority of foodborne illnesses. Bacteria are responsible by the vast majority of foodborne illnesses. Bacteria can be divided into 3 types; Bacteria can be divided into 3 types; *Harmful or pathogenic. *Harmful or pathogenic. *Beneficial *Beneficial *Spoilage *Spoilage

19 19 Bacteria Bacteria grow and reproduce logarithmically Bacteria grow and reproduce logarithmically Under the right conditions, bacteria can reproduce very rapidly. Under the right conditions, bacteria can reproduce very rapidly. Bacteria can be killed by high temperatures. Bacteria can be killed by high temperatures. Bacteria grow slower at low temperatures. Bacteria grow slower at low temperatures. Bacteria can survive freezing. Bacteria can survive freezing. Some bacteria are spore-formers and are very resistant to conditions that kill most bacteria (e.g heat, drying, chemicals) Some bacteria are spore-formers and are very resistant to conditions that kill most bacteria (e.g heat, drying, chemicals)

20 20 CONDITIONS AFFECTING BACTERIAL GROWTH There are 6 conditions affecting bacterial growth and can be remembered by the anagram There are 6 conditions affecting bacterial growth and can be remembered by the anagram FAT TOM. *Food *Food *Acidity *Acidity * Time * Time *Temperature *Temperature *Oxygen *Oxygen * Moisture * Moisture

21 21 Conditions Affecting Bacterial Growth FOOD * Bacteria need food to reproduce. * Bacteria need food to reproduce. *High protein foods and moist starchy foods *High protein foods and moist starchy foods promote bacterial growth but any food can promote bacterial growth but any food can be potentially risky is not handled properly. be potentially risky is not handled properly.

22 22 Photo courtesy of USDA

23 23 Conditions Affecting Bacterial Growth ACIDITY pH-measure of acidity or alkalinity. (pH =7 is neutral; 1=acid; 14=basic). pH-measure of acidity or alkalinity. (pH =7 is neutral; 1=acid; 14=basic). Most bacteria prefer a pH of Most bacteria prefer a pH of Most bacteria will not grow at a pH of 4.6 or less (acid). This is why fermented foods such as sauerkraut (fermented cabbage) and fermented sausages were historically used in Europe. Most bacteria will not grow at a pH of 4.6 or less (acid). This is why fermented foods such as sauerkraut (fermented cabbage) and fermented sausages were historically used in Europe.

24 24 pH RANGES OF BACTERIA Bacteria Bacteria Molds Molds Yeasts Yeasts Salmonella Salmonella Clostridium Botulinum Clostridium Botulinum Clostridium perfringens Clostridium perfringens Listeria monocytogenes Listeria monocytogenes Campylobacter Campylobacter pH Range

25 25 pH RANGES FOR FOODS Food Food Meat Meat Chicken Chicken Fish Fish Fruit Fruit Apples Apples Grapes Grapes Vegetables Vegetables Carrot Carrot Corn Corn Dairy Dairy Milk Milk Cheese Cheese pH Range

26 26 Conditions Affecting Bacterial Growth Temperature Temperature Bacteria proliferation can be controlled by Bacteria proliferation can be controlled by both heat and cold. both heat and cold. Bacteria generally do not grow at freezer Bacteria generally do not grow at freezer temperatures but they can survive. temperatures but they can survive. Use of refrigeration temperatures (30-45F) Use of refrigeration temperatures (30-45F) slows down the rate of bacterial slows down the rate of bacterial proliferation. The colder the better. proliferation. The colder the better.

27 27 BACTERIAL THERMOMETER Degrees F Degrees F  Bacterial Action Resistant spores killed Boiling point of water Resistant Salmonella kill Vegetative cells killed Trichina killed DANGER ZONE Bacteria double-20 min Bacteria double-1 hour Bacteria double-2 hours Bacteria double –6 hours Bacteria double-20 hours Bacteria double –60 hours Lower limit for bacteria

28 28 The Use of Heat There are two important words to define; There are two important words to define; *Pasteurization refers to the cooking of food where only a certain number of bacteria are killed. Pasteurization does not render the product sterile. *Pasteurization refers to the cooking of food where only a certain number of bacteria are killed. Pasteurization does not render the product sterile. *Sterilization refers to the total destruction of all living organisms and is only used in canned shelf- stable items. *Sterilization refers to the total destruction of all living organisms and is only used in canned shelf- stable items.

29 29 The Use of Heat Clostridium botulinum is a bacteria that can form spores that are very resistant to heat. It produces a toxin that causes paralysis and is often fatal. It grows well in an anaerobic (no oxygen), warm (60-115F) environment. Clostridium botulinum is a bacteria that can form spores that are very resistant to heat. It produces a toxin that causes paralysis and is often fatal. It grows well in an anaerobic (no oxygen), warm (60-115F) environment. Unless a food goes through the canning procedure (cook in a retort or pressure device of F for several hours) it is assumed to have Clostridium spores are present. Unless a food goes through the canning procedure (cook in a retort or pressure device of F for several hours) it is assumed to have Clostridium spores are present.

30 30 Photo courtesy of USDA

31 31 The Use of Heat Remember that Clostridium grow best at F so you must cool all foods fast after heating. It is recommended to chill foods down from 140F to 40F within 4 hours. Remember that Clostridium grow best at F so you must cool all foods fast after heating. It is recommended to chill foods down from 140F to 40F within 4 hours. Remember to assume that all foods except shelf- stable canned foods and high acid foods contain Clostridium spores and treat them with the proper precautions. Remember to assume that all foods except shelf- stable canned foods and high acid foods contain Clostridium spores and treat them with the proper precautions.

32 32 Conditions Affecting Bacterial Growth TIME Under optimal conditions, some bacteria can double every 20 minutes. Under optimal conditions, some bacteria can double every 20 minutes. The colder the storage temperature, the longer the potential shelflife. The colder the storage temperature, the longer the potential shelflife. Potentially hazardous foods should not remain in the danger zone (140-40F) for more than 4 hours during the entire food handling process. Potentially hazardous foods should not remain in the danger zone (140-40F) for more than 4 hours during the entire food handling process.

33 33 Conditions Affecting Bacterial Growth Oxygen Some bacteria require oxygen to grow (aerobic). Some bacteria require oxygen to grow (aerobic). Some bacteria will only grow in the absence of oxygen (anaerobic). Some bacteria will only grow in the absence of oxygen (anaerobic). Some bacteria can grow either with or without oxygen (facultative). Most pathogenic bacteria are in this category. Some bacteria can grow either with or without oxygen (facultative). Most pathogenic bacteria are in this category.

34 34 Conditions Effecting Bacterial Growth Moisture The amount of water available in food for chemical reactions and microbial growth is called water activity (Aw). The amount of water available in food for chemical reactions and microbial growth is called water activity (Aw). Water activity is measured from 0 (totally dry) to 1.0 (pure water). Water activity is measured from 0 (totally dry) to 1.0 (pure water). Disease-causing bacteria can only grow in foods that have a water activity higher than Disease-causing bacteria can only grow in foods that have a water activity higher than The water activity available in foods can be reduced by freezing, dehydration or adding salt or sugar. The water activity available in foods can be reduced by freezing, dehydration or adding salt or sugar.

35 35 WATER ACTIVITY OF SOME FOODS Aw/ Microorganism Aw/ Microorganism Bacteria Bacteria Yeasts Molds No microorganisms proliferate proliferate Foods Meat, fish, sausage, milk Cheese, cured meat (ham), fruit juice conc Fermented sausages (salami), dry cheeses, margarine Juice conc, syrups, flour, fruit cakes, honey, jellies, preserves Cookies, crackers, bread crusts

36 36 Potentially Hazardous Foods (PHF) Defined as a food that is natural or synthetic and that requires temperature control because it is in a form capable of supporting rapid microbial growth. Defined as a food that is natural or synthetic and that requires temperature control because it is in a form capable of supporting rapid microbial growth.

37 37 Potentially Hazardous Foods Are most often responsible for outbreaks of foodborne illness Are most often responsible for outbreaks of foodborne illness Includes foods with high protein content such as meat, poultry, fish and dairy products. Includes foods with high protein content such as meat, poultry, fish and dairy products. Includes some low-protein foods, moist starchy foods as well as cooked rice, coleslaw, garlic in oil, and sliced watermelon. Includes some low-protein foods, moist starchy foods as well as cooked rice, coleslaw, garlic in oil, and sliced watermelon. PHF’s generally have near-neutral pH levels (5.0 or higher) and a high moisture content PHF’s generally have near-neutral pH levels (5.0 or higher) and a high moisture content (water activity higher than 0.91). (water activity higher than 0.91).

38 38 Potentially Hazardous Foods Meat & Meat products Meat & Meat products Poultry Poultry Fish Fish Shellfish Shellfish Raw eggs Raw eggs Milk Milk Dairy products Dairy products Garlic-in-oil mixtures Gravies Creamed soups Custards/Puddings Protein salads Sauces (esp cream sauces) Cream-filled baked goods.

39 39 PATHOGENS OF INTEREST Salmonella spp Salmonella spp Shigella spp Shigella spp Clostridium perfringens Clostridium perfringens Staphylococcus aureus Staphylococcus aureus Campylobacter jejuni Campylobacter jejuni Bacillus cereus Bacillus cereus Listeria monocytogenes Clostridium botulinum Eschericha coli 0157:H7 Vibrio parahaemolyticus and vulnificus Yersinia enterocolitica

40 % of Foodborne Illnesses from Bacteria come from just 4 Bacteria Campylobacter Campylobacter Salmonella Salmonella Clostridium perfringens Clostridium perfringens Staphylococcus aureus Staphylococcus aureus

41 41 OTHER PATHOGENS DISEASE PATHOGEN DISEASE PATHOGEN Anthrax Bacillus anthrax Diphtheria Corynebacterium diphtheriae Tuberculosis Microbacterium tuberculosis Scarlet/Rheumatic fever- Streptococcus pyogenes Cholera Vibrio cholerae Gonorrhea Neisseria gonorrhea Plaque Yersinia pestis

42 42 FOODBORNE DISEASES Defined as a disease that is carried or transmitted to humans by food. Defined as a disease that is carried or transmitted to humans by food. The 3 types of foodborne diseases are: The 3 types of foodborne diseases are: *Foodborne infection *Foodborne infection *Foodborne intoxication or poisoning *Foodborne intoxication or poisoning *Foodborne toxico-infection. *Foodborne toxico-infection.

43 43 Foodborne Infection Foodborne infection results from eating food containing living harmful microorganisms. The microorganisms multiply in the body, invades and penetrates the intestinal walls causing illness. Foodborne infection results from eating food containing living harmful microorganisms. The microorganisms multiply in the body, invades and penetrates the intestinal walls causing illness.

44 44 FoodBorne Infections Salmonella Salmonella Listeria monocytogenes Listeria monocytogenes Campylobacter jejuni Campylobacter jejuni Yersinia enterocolitica Yersinia enterocolitica

45 45 Foodborne Intoxication Foodborne intoxication or food poisoning resulting from eating food containing toxins or poisons produced by microorganisms that may not be present anymore. Examples include; Foodborne intoxication or food poisoning resulting from eating food containing toxins or poisons produced by microorganisms that may not be present anymore. Examples include;

46 46 FoodBorne Intoxication Staphylococcus aureus Staphylococcus aureus Bacillus cereus Bacillus cereus Clostridium botulinum Clostridium botulinum

47 47 Foodborne Toxico-Mediated Infection Foodborne toxico-mediated infection results from eating a food containing a large amount of disease-causing microorganisms, which grow in the intestines and produce toxins. Foodborne toxico-mediated infection results from eating a food containing a large amount of disease-causing microorganisms, which grow in the intestines and produce toxins. Clostridium perfringens, Bacillus cereus, E. Coli 0157;H7 and Shigella are examples. Clostridium perfringens, Bacillus cereus, E. Coli 0157;H7 and Shigella are examples.

48 48 Let’s now go through some of the more common bacterial pathogens in food

49 49 SALMONELLOSIS Caused by the bacteria Salmonella. Caused by the bacteria Salmonella. Salmonella is non-spore forming, is facultative and some strains can grow at pH range below 4.5. Salmonella is non-spore forming, is facultative and some strains can grow at pH range below 4.5. Causes a foodborne infection. Causes a foodborne infection. Symptoms include abdominal cramps, headache, nausea, fever, diarrhea and sometimes vomiting. Symptoms include abdominal cramps, headache, nausea, fever, diarrhea and sometimes vomiting. May cause severe dehydration in infants and elderly. May cause severe dehydration in infants and elderly.

50 50 Salmonella Enteriditis Photo courtesy of USDA

51 51 Salmonellosis Sources of contamination include water, soil, insects, domestic and wild animals and the human intestinal tract. Sources of contamination include water, soil, insects, domestic and wild animals and the human intestinal tract. Foods that have been associated with Salmonella contamination include; Foods that have been associated with Salmonella contamination include; *High protein foods (meat, poultry, fish and *High protein foods (meat, poultry, fish and milk). milk). *Egg and egg products such as custards, *Egg and egg products such as custards, sauces and pastry creams. sauces and pastry creams. *Raw produce that has been contaminated *Raw produce that has been contaminated by fecal matter. by fecal matter.

52 52 Salmonellosis Preventative measures include; Preventative measures include; *Avoid cross contamination *Avoid cross contamination *Refrigerate foods properly *Refrigerate foods properly *Thoroughly cook all foods to minimum *Thoroughly cook all foods to minimum internal temperatures. internal temperatures. *Properly cool meat and egg products after *Properly cool meat and egg products after cooking. cooking. *Ensure that employees avoid *Ensure that employees avoid contaminating food and food-contact contaminating food and food-contact surfaces by practicing good personal surfaces by practicing good personal hygiene. hygiene.

53 53 Salmonella Typhi Photo courtesy of USDA

54 54 SHIGELLOSIS Shigella do not produce spores, are facultative and some strains produce shiga toxin. Shigella do not produce spores, are facultative and some strains produce shiga toxin. Shigellosis is a toxin-mediated infection. Shigellosis is a toxin-mediated infection. Symptoms include diarrhea (may be bloody), abdominal pain, fever, nausea, cramps, vomiting, chills, fatigue and dehydration. Symptoms include diarrhea (may be bloody), abdominal pain, fever, nausea, cramps, vomiting, chills, fatigue and dehydration. Infant day-care centers are a common source Infant day-care centers are a common source

55 55 Shigellosis Preventative measures include; Preventative measures include; *Avoid cross contamination *Avoid cross contamination *Ensure food handlers use good personal *Ensure food handlers use good personal hygiene hygiene *Use approved water source. *Use approved water source. *Control flies *Control flies *Cool foods rapidly. *Cool foods rapidly.

56 56 LISTERIOSIS Listeria monocytogenes does not form spores, is facultative, resists freezing, drying and heat and can grow at refrigeration temperatures. Listeria monocytogenes does not form spores, is facultative, resists freezing, drying and heat and can grow at refrigeration temperatures. Is considered a foodborne infection. Is considered a foodborne infection. Symptoms include nausea, vomiting, diarrhea, headache, persistent fever, chills, backache, meningitis, encephalitis and septicemia. Symptoms include nausea, vomiting, diarrhea, headache, persistent fever, chills, backache, meningitis, encephalitis and septicemia. Most often affects infants, pregnant women and their fetuses, immune-compromised and organ transplant patients.. Most often affects infants, pregnant women and their fetuses, immune-compromised and organ transplant patients..

57 57 Listeria Monocytogenes Photo courtesy of USDA

58 58 LISTERIOSIS Foods associated with Listeria include; Foods associated with Listeria include; *Unpasteurized milk and milk *Unpasteurized milk and milk products. products. *Raw vegetables *Raw vegetables *Poultry, meat, seafood *Poultry, meat, seafood *Prepared and ready to eat foods *Prepared and ready to eat foods *Pregnant women should avoid in-store sliced *Pregnant women should avoid in-store sliced deli meats, soft cheeses and smoked salmon. deli meats, soft cheeses and smoked salmon.

59 59 LISTERIOSIS Preventative measures include; Preventative measures include; *Use only pasteurized milk and dairy *Use only pasteurized milk and dairy products. products. *Cook foods to proper internal *Cook foods to proper internal temperatures. temperatures. *Avoid cross contamination. *Avoid cross contamination. *Clean and sanitize food contact surfaces. *Clean and sanitize food contact surfaces.

60 60 CLOSTRIDIUM PERFRINGENS Clostridium perfringens form spores and is anaerobic. Clostridium perfringens form spores and is anaerobic. Causes a toxin-mediated infection. Causes a toxin-mediated infection. Symptoms include abdominal pain, diarrhea, nausea, dehydration (fever, headache and vomiting are usually absent). Symptoms include abdominal pain, diarrhea, nausea, dehydration (fever, headache and vomiting are usually absent). Sources of contamination include human and animal intestinal tracts and soil (especially contaminated with feces) Sources of contamination include human and animal intestinal tracts and soil (especially contaminated with feces)

61 61 Clostridium Perfringens Foods associated with contamination include meat, meat products, poultry, stew, gravy and beans that have been improperly cooked. Foods associated with contamination include meat, meat products, poultry, stew, gravy and beans that have been improperly cooked. The most common preventive methods include the control of time and temperature of cooking and cooling, reheating cooked foods and adequate refrigeration. The most common preventive methods include the control of time and temperature of cooking and cooling, reheating cooked foods and adequate refrigeration.

62 62 Staphylococcal Food Poisoning Staphylococcus aureas does not form spores, is facultative and is very heat sensitive. Staphylococcus aureas does not form spores, is facultative and is very heat sensitive. Causes a foodborne intoxication or poisoning. Causes a foodborne intoxication or poisoning. Symptoms include nausea, vomiting, abdominal cramps, and diarrhea. Symptoms include nausea, vomiting, abdominal cramps, and diarrhea. Sources of contamination include skin, hair, nose, throat, infected sores (boils & whiteheads) and animals. Sources of contamination include skin, hair, nose, throat, infected sores (boils & whiteheads) and animals.

63 63 Staphylococcal Food Poisoning Foods associated with contamination include meat, poultry, egg products, milk and dairy products, potato salad, custards and salad dressings. Foods associated with contamination include meat, poultry, egg products, milk and dairy products, potato salad, custards and salad dressings. Preventative measures include; Preventative measures include; *Properly cook all foods. *Properly cook all foods. *Practice good personal hygiene *Practice good personal hygiene *Properly refrigerate all foods. *Properly refrigerate all foods. *Rapidly cool prepared foods. *Rapidly cool prepared foods.

64 64 BACILLUS CEREUS Bacillus cereus forms spores and is facultative. Bacillus cereus forms spores and is facultative. It causes both toxin-mediated infections (causing diarrhea) and intoxication (causing vomiting). It causes both toxin-mediated infections (causing diarrhea) and intoxication (causing vomiting). Symptoms; Symptoms; *Infection-watery diarrhea, abdominal *Infection-watery diarrhea, abdominal cramps, pain, nausea. cramps, pain, nausea. *Intoxication-nausea and vomiting; *Intoxication-nausea and vomiting; sometimes abdominal cramps and diarrhea. sometimes abdominal cramps and diarrhea.

65 65 Bacillus Cereus Sources of contamination include soil and dust, cereal crops, skin infection (whiteheads on skin). Sources of contamination include soil and dust, cereal crops, skin infection (whiteheads on skin). Cooking kills the vegetative cells but can cause spores to germinate, making reheated foods a problem. Cooking kills the vegetative cells but can cause spores to germinate, making reheated foods a problem. Foods involved; Foods involved; *Infection-meat, milk, vegetables, fish. *Infection-meat, milk, vegetables, fish. *Intoxication-rice products, starchy foods, *Intoxication-rice products, starchy foods, sauces, puddings, soups. sauces, puddings, soups.

66 66 Bacillus Cereus Preventative methods include; Preventative methods include; *Careful time and temperature control *Careful time and temperature control *Quick chilling methods to cool foods. *Quick chilling methods to cool foods. *Adequate cooking of foods. *Adequate cooking of foods.

67 67 BOTULISM Clostridium botulinum forms spores and is anaerobic. Clostridium botulinum forms spores and is anaerobic. Causes food intoxication or poisoning. Causes food intoxication or poisoning. Symptoms include vomiting and constipation or diarrhea initially with progressive fatigue, weakness, vertigo, blurred or double vision, breathing paralysis, dry mouth eventually leading to paralysis and death. Symptoms include vomiting and constipation or diarrhea initially with progressive fatigue, weakness, vertigo, blurred or double vision, breathing paralysis, dry mouth eventually leading to paralysis and death.

68 68 Botulism Has been found in almost all foods but initially coming from soil and water. Has been found in almost all foods but initially coming from soil and water. Preventative methods include; Preventative methods include; *Treat all foods as if present. *Treat all foods as if present. *Keep cold foods cold. *Keep cold foods cold. *Be careful of home canned foods. *Be careful of home canned foods. *Use time/temperature control of large, *Use time/temperature control of large, bulky foods. bulky foods. *Rapidly cool leftovers. *Rapidly cool leftovers.

69 69 CAMPYLOBACTERIOSIS Campylobacter jejuni does not form spores. Campylobacter jejuni does not form spores. Causes a foodborne infection. Causes a foodborne infection. Symptoms include bloody diarrhea, fever, nausea, vomiting, abdominal pain, headache and muscle pain. Symptoms include bloody diarrhea, fever, nausea, vomiting, abdominal pain, headache and muscle pain. Sources of contamination include domestic and wild animals. Sources of contamination include domestic and wild animals.

70 70 Campylobacter Fetus Photo courtesy of USDA

71 71 Campylobacteriosis Foods associated with contamination include unpasteurized milk and dairy products, raw poultry and non-chlorinated or fecal-contaminated water. Foods associated with contamination include unpasteurized milk and dairy products, raw poultry and non-chlorinated or fecal-contaminated water. Preventative methods include; Preventative methods include; *Thoroughly cook food to minimum safe internal *Thoroughly cook food to minimum safe internal temperatures. temperatures. *Use only pasteurized milk and dairy products. *Use only pasteurized milk and dairy products. *Use approved water source *Use approved water source *Avoid cross-contamination. *Avoid cross-contamination.

72 72 Escherichia Coli 0157:H7 E. Coli does not form spores, is facultative and has survived freezing and low pH (below pH 4.0). Can grow at refrigeration temperatures. E. Coli does not form spores, is facultative and has survived freezing and low pH (below pH 4.0). Can grow at refrigeration temperatures. Causes a toxin-mediated infection. Causes a toxin-mediated infection. Symptoms include diarrhea (may become bloody), severe abdominal cramps, kidney failure and possibly death. Symptoms include diarrhea (may become bloody), severe abdominal cramps, kidney failure and possibly death. Source of contamination is from the GI tract of animals and humans. Source of contamination is from the GI tract of animals and humans.

73 73 E.Coli 0157:H7 Food associated include: Food associated include: *Raw or undercooked meat and *Raw or undercooked meat and poultry. poultry. *Unpasteurized milk and dairy *Unpasteurized milk and dairy products and fruit juices. products and fruit juices. *Vegetables from manure fertilized fields. *Vegetables from manure fertilized fields. *Non-chlorinated water. *Non-chlorinated water.

74 74 E. Coli 0157:H7 Preventative methods include: Preventative methods include: *Thoroughly cook all foods to safe *Thoroughly cook all foods to safe temperatures. temperatures. *Beware of unpasteurized dairy *Beware of unpasteurized dairy products and fruit juices. products and fruit juices. *Use approved water sources. *Use approved water sources. *Avoid cross-contamination. *Avoid cross-contamination.

75 75 VIBRIO Spp Vibrio parahaemolyticus and Vibrio vulnificus do not form spores; More common in warmer months. Vibrio parahaemolyticus and Vibrio vulnificus do not form spores; More common in warmer months. Results in foodborne infection. Results in foodborne infection. Symptoms include diarrhea, abdominal cramps, nausea, vomiting, headache and sometimes death in immuno-compromised individuals. Symptoms include diarrhea, abdominal cramps, nausea, vomiting, headache and sometimes death in immuno-compromised individuals.

76 76 Vibrio Spp Most commonly found in oysters and shellfish from the Gulf of Mexico. Most commonly found in oysters and shellfish from the Gulf of Mexico. Foods involved are raw or partially cooked oysters and shellfish. Foods involved are raw or partially cooked oysters and shellfish. Preventative measures include; Preventative measures include; *Avoid eating raw or undercooked seafood. *Avoid eating raw or undercooked seafood. *Avoid cross-contamination. *Avoid cross-contamination. *Keep all seafood frozen until ready to eat. *Keep all seafood frozen until ready to eat.

77 77 YERSINIOSIS Yersinia enterocolitica does not form spores, is facultative, can survive at a pH below 4.5 and can grow at refrigeration temperatures. Yersinia enterocolitica does not form spores, is facultative, can survive at a pH below 4.5 and can grow at refrigeration temperatures. Causes a foodborne infection usually in young people ( years old). Causes a foodborne infection usually in young people ( years old). Symptoms include fever and severe abdominal pain (mimics appendicitis). Possibly diarrhea, headache, sore throat or vomiting. Symptoms include fever and severe abdominal pain (mimics appendicitis). Possibly diarrhea, headache, sore throat or vomiting.

78 78 Yersiniosis Source is soil, water, domestic and wild animals, rodents. Source is soil, water, domestic and wild animals, rodents. Foods most commonly involved include meats, oysters and fish, unpasteurized milk and dairy products and non-chlorinated water. Foods most commonly involved include meats, oysters and fish, unpasteurized milk and dairy products and non-chlorinated water.

79 79 Yersiniosis Preventative measures include; Preventative measures include; *Thoroughly cook foods to minimum *Thoroughly cook foods to minimum safe internal temperatures safe internal temperatures *Avoid cross-contamination. *Avoid cross-contamination. *Use approved water source. *Use approved water source.

80 80 FUNGI

81 81 Fungi Fungi are larger than bacteria. Fungi are larger than bacteria. Prefer foods that are high in sugar or starch. Prefer foods that are high in sugar or starch. Are spoilage organisms that cause food to deteriorate. Are spoilage organisms that cause food to deteriorate. May produce toxic chemicals called mycotoxins. May produce toxic chemicals called mycotoxins. Examples are molds and yeasts. Examples are molds and yeasts.

82 82 MOLD Many molds are beneficial Many molds are beneficial *Important to medicine (i.e. penicillin). *Important to medicine (i.e. penicillin). *Important in food production (i.e. *Important in food production (i.e. cheese-making). cheese-making).

83 83 MOLD Can withstand extreme conditions; Can withstand extreme conditions; *Molds prefer warmer temperatures but *Molds prefer warmer temperatures but can survive and grow at cooler can survive and grow at cooler temperatures. temperatures. *Molds have the ability to tolerate salt, *Molds have the ability to tolerate salt, sugar and acids. sugar and acids. *Some molds produce poisons called *Some molds produce poisons called mycotoxins which can cause cancer such as liver mycotoxins which can cause cancer such as liver cancer and other illnesses. cancer and other illnesses.

84 84 MYCOTOXINS Symptoms of aflatoxicosis include acute on-set hemorrhage and fluid buildup. Symptoms of aflatoxicosis include acute on-set hemorrhage and fluid buildup. Common sources of mycotoxins include moldy grain, corn, peanuts, pecans, walnuts and milk. Common sources of mycotoxins include moldy grain, corn, peanuts, pecans, walnuts and milk. Preventive methods include; Preventive methods include; *Keep food covered to prevent exposure to *Keep food covered to prevent exposure to mold spores. mold spores. *Purchase food from a reputable supplier. *Purchase food from a reputable supplier. *Keep grain and nuts dry. *Keep grain and nuts dry.

85 85 YEASTS Spoils the quality of foods. Not usually a food safety hazard. Spoils the quality of foods. Not usually a food safety hazard. Requires carbohydrates and moisture to survive. Requires carbohydrates and moisture to survive. Serves as an agent in fermentation and leavening. You can see the bubbles and smell/taste alcoholic characteristics. Serves as an agent in fermentation and leavening. You can see the bubbles and smell/taste alcoholic characteristics. Can detract from the flavor of some foods. Can detract from the flavor of some foods. Easily killed by heating to 136F for 15 minutes. Easily killed by heating to 136F for 15 minutes.

86 86 PARASITES

87 87 PARASITES Parasites are tiny organisms that require a living host for growth and nourishment. The most common include Parasites are tiny organisms that require a living host for growth and nourishment. The most common include Trichinella spiralis. Trichinella spiralis. Anisakis Anisakis Giardia duodenalis Giardia duodenalis Cryptosporidium pavum Cryptosporidium pavum Toxoplasma gondii Toxoplasma gondii Cyclospora cayentanensis Cyclospora cayentanensis

88 88 TRICHINOSIS Caused by the parasite Trichinella spiralis, a roundworm that burrows into the muscle of the host and causes infection. Caused by the parasite Trichinella spiralis, a roundworm that burrows into the muscle of the host and causes infection. Early symptoms include nausea, diarrhea, abdominal pain, occasional vomiting, swelling around the eyes and fever. Early symptoms include nausea, diarrhea, abdominal pain, occasional vomiting, swelling around the eyes and fever. Later symptoms include muscle soreness, thirst, extreme sweating, chills, bleeding and fatigue. Later symptoms include muscle soreness, thirst, extreme sweating, chills, bleeding and fatigue.

89 89 Trichinosis Generally from meat animals that eat off the ground or in garbage dumps. Generally from meat animals that eat off the ground or in garbage dumps. Pork used to be the common vehicle to humans but proper cooking and the fact that hogs are now reared in confinement have reduced the incidence. Pork used to be the common vehicle to humans but proper cooking and the fact that hogs are now reared in confinement have reduced the incidence. Wild game such as bears and raccoons are the most common carriers. Wild game such as bears and raccoons are the most common carriers.

90 90 Trichinosis Methods of prevention include: Methods of prevention include: *Cook pork and all meats to minimum *Cook pork and all meats to minimum internal cooking temperatures. internal cooking temperatures. *Wash, rinse and sanitize equipment *Wash, rinse and sanitize equipment such as sausage grinders and such as sausage grinders and utensils used in the preparation of utensils used in the preparation of raw pork and other meats. raw pork and other meats.

91 91 Anisakiasis Food sources include raw, undercooked or improperly frozen seafood, especially cod, haddock, fluke, pacific salmon, herring, flounder and fish used in sushi and sashimi Food sources include raw, undercooked or improperly frozen seafood, especially cod, haddock, fluke, pacific salmon, herring, flounder and fish used in sushi and sashimi

92 92 Anisakiasis Preventative methods include; Preventative methods include; *Properly freezing fish. Fish to be *Properly freezing fish. Fish to be eaten raw should be frozen at –4F eaten raw should be frozen at –4F or lower for 15 hours in a blast or lower for 15 hours in a blast chiller. chiller. *Avoid eating raw or partially cooked *Avoid eating raw or partially cooked fish and shellfish. fish and shellfish.

93 93 GIARDIASIS An infection resulting from the protozoan Giardia duodenalis. An infection resulting from the protozoan Giardia duodenalis. Symptoms include fatigue, nausea, intestinal gas, weakness, weight loss and abdominal cramps. Symptoms include fatigue, nausea, intestinal gas, weakness, weight loss and abdominal cramps.

94 94 Giardiasis Food sources include water or raw vegetables that are contaminated by animal waste or infected water. Food sources include water or raw vegetables that are contaminated by animal waste or infected water. Prevention methods include; Prevention methods include; *Wash raw produce thoroughly. *Wash raw produce thoroughly. *Use approved water source *Use approved water source *Ensure that food handlers practice *Ensure that food handlers practice good hygiene. good hygiene.

95 95 TOXOPLASMOSIS Caused by the protozoan Toxoplasma gondii. Caused by the protozoan Toxoplasma gondii. Often there are no symptoms. Often there are no symptoms. When symptoms occur, they include enlarged lymph nodes in the head and neck, severe headaches, muscle pain and rash. When symptoms occur, they include enlarged lymph nodes in the head and neck, severe headaches, muscle pain and rash. Individuals with compromised immune systems such as HIV-infected people and pregnant women and their fetuses are at most risk. Individuals with compromised immune systems such as HIV-infected people and pregnant women and their fetuses are at most risk. It is not passed by person to person contact. Cats are a common source. Pregnant women should avoid emptying cat litter box. It is not passed by person to person contact. Cats are a common source. Pregnant women should avoid emptying cat litter box.

96 96 Toxoplasmosis Food sources include raw or undercooked meat especially pork, lamb, venison and raw vegetables. Food sources include raw or undercooked meat especially pork, lamb, venison and raw vegetables. Preventative methods include; Preventative methods include; *Avoid raw and undercooked meats *Avoid raw and undercooked meats *Cook meats to the minimum internal *Cook meats to the minimum internal temperature so there is no pink inside. temperature so there is no pink inside. *Keep cats away from food preparation *Keep cats away from food preparation areas. areas. *Wash hands that come in contact with *Wash hands that come in contact with soil, raw meat, cat feces and raw soil, raw meat, cat feces and raw vegetables. vegetables.

97 97 CYCLOSPORIASIS Caused by the protozoan Cyclospora cayentanesis. Caused by the protozoan Cyclospora cayentanesis. Symptoms include watery diarrhea, loss of appetite, weight loss, bloating, gas, abdominal cramps, nausea, vomiting, muscle aches and fatigue. Symptoms include watery diarrhea, loss of appetite, weight loss, bloating, gas, abdominal cramps, nausea, vomiting, muscle aches and fatigue.

98 98 Cyclosporiasis Food sources include water, raspberries, strawberries and other fresh produce. Food sources include water, raspberries, strawberries and other fresh produce. Preventive methods include; Preventive methods include; *Thoroughly wash all produce *Thoroughly wash all produce *Use approved water source *Use approved water source *Ensure that food handlers used good *Ensure that food handlers used good personal hygiene. personal hygiene.

99 99 VIRUSES

100 100 VIRUSES Multiply only in living cells (hosts) and are fairly hard to kill while in humans. Multiply only in living cells (hosts) and are fairly hard to kill while in humans. They do not multiple in food. They do not multiple in food. Usually killed during the cooking process. Usually killed during the cooking process. Food may become infected after cooking by human carriers or by contaminated water. Food may become infected after cooking by human carriers or by contaminated water.

101 101 Photo courtesy of USDA

102 102 Examples of Viruses Hepatitis A Hepatitis A Norwalk Virus Norwalk Virus Rotavirus Rotavirus HIV Virus HIV Virus

103 103 Hepatitis A Virus Hepatitus A or Hepatovirus causes an infection of the liver. Hepatitus A or Hepatovirus causes an infection of the liver. Symptoms include discomfort, fatigue, headache, nausea, loss of appetite, vomiting, abdominal pain and jaundice and may appear weeks/months after exposure. Symptoms include discomfort, fatigue, headache, nausea, loss of appetite, vomiting, abdominal pain and jaundice and may appear weeks/months after exposure. Transmitted to foods either by poor personal hygiene or contaminated water. Human feces is the main reservoir. Transmitted to foods either by poor personal hygiene or contaminated water. Human feces is the main reservoir.

104 104 Hepatitis A Virus Food sources that may be contaminated include water, ice, shellfish, cold cuts and sandwiches, milk or dairy products or any food that does not receive a further heat treatment. Also, fruits and vegetables that are washed with infected water or contaminated by infected humans or animals may contain Hepatitis A. Food sources that may be contaminated include water, ice, shellfish, cold cuts and sandwiches, milk or dairy products or any food that does not receive a further heat treatment. Also, fruits and vegetables that are washed with infected water or contaminated by infected humans or animals may contain Hepatitis A.

105 105 Hepatitus A Virus Preventive methods include; Preventive methods include; *Prevent cross contamination from *Prevent cross contamination from hands hands *Ensure that food handlers practice *Ensure that food handlers practice good personal hygiene. good personal hygiene. *Clean and sanitize food contact *Clean and sanitize food contact surfaces. surfaces. *Use approved water sources. *Use approved water sources.

106 106 Photo courtesy of USDA

107 107 Norwalk Virus Gastroenteritis The Norwalk virus agent causes an infection of the stomach and intestines. The Norwalk virus agent causes an infection of the stomach and intestines. Symptoms include nausea, vomiting, diarrhea, abdominal cramps, headache and mild fever. May appear weeks/months after exposure. Symptoms include nausea, vomiting, diarrhea, abdominal cramps, headache and mild fever. May appear weeks/months after exposure. Transmitted to food by either poor personal hygiene or contaminated water. Transmitted to food by either poor personal hygiene or contaminated water.

108 108 Norwalk Virus Food sources that may be contaminated include water, shellfish and raw fruits and vegetables that are washed with infected water or contaminated by infected humans or animals. Food sources that may be contaminated include water, shellfish and raw fruits and vegetables that are washed with infected water or contaminated by infected humans or animals.

109 109 Norwalk Virus Preventive methods include; Preventive methods include; *Prevention of cross contamination from *Prevention of cross contamination from hands. hands. *Ensure that food handlers practice *Ensure that food handlers practice good personal hygiene. good personal hygiene. *Thoroughly cook foods to minimum *Thoroughly cook foods to minimum safe internal temperatures. safe internal temperatures. *Use approved water sources. *Use approved water sources.

110 110 ROTAVIRUS GASTROENTERITIS Rotavirus causes an infection of the stomach and the intestines. Rotavirus causes an infection of the stomach and the intestines. Symptoms include vomiting and diarrhea, abdominal pain and mild fever. Illness more common in children than adults. Symptoms include vomiting and diarrhea, abdominal pain and mild fever. Illness more common in children than adults.

111 111 Rotavirus Preventive methods include: Preventive methods include: *Ensure food handlers practice good *Ensure food handlers practice good personal hygiene. personal hygiene. *Thoroughly cook food to minimum *Thoroughly cook food to minimum safe internal temperatures. safe internal temperatures. *Use approved water source. *Use approved water source.

112 112 HIV VIRUS The Human Immunodeficiency Virus is NOT a foodborne illness. The Human Immunodeficiency Virus is NOT a foodborne illness. HIV- infected people can work with food unless they have a secondary infection or communicable illness with symptoms including vomiting, diarrhea, fever, sore throat or jaundice. HIV- infected people can work with food unless they have a secondary infection or communicable illness with symptoms including vomiting, diarrhea, fever, sore throat or jaundice.

113 113 MAD COW DISEASE Mad cow disease is believed to be caused by prions which are proteins thought to originate as regular components of neurological tissues in animals. Mad cow disease is believed to be caused by prions which are proteins thought to originate as regular components of neurological tissues in animals. When these proteins become abnormally shaped, they are able to transform molecules of normally shaped protein with which they come in contact to the abnormal prion configuration. When these proteins become abnormally shaped, they are able to transform molecules of normally shaped protein with which they come in contact to the abnormal prion configuration. This process is repeated numerous times until the number of abnormally-shaped molecules causes overt illness. This process is repeated numerous times until the number of abnormally-shaped molecules causes overt illness.

114 114 MAD COW DISEASE Transmission is only through nerve tissue. Transmission is only through nerve tissue. Mad cow is one of a group of diseases called Transmissible Spongiform Encephalopathies which include; Mad cow is one of a group of diseases called Transmissible Spongiform Encephalopathies which include; - Creutzfeldt-Jacob disease in humans - Creutzfeldt-Jacob disease in humans -Scrapie in sheep and goats -Scrapie in sheep and goats -Chronic Wasting Disease in deer and elk -Chronic Wasting Disease in deer and elk in Wisconsin and Colorado. in Wisconsin and Colorado.

115 115 References To learn more about the pathogenic bacteria, parasites, viruses and Mad cow (prions), go to the U.S. Food &Drug Administrations “Bad Bugs Book” on-line at ; To learn more about the pathogenic bacteria, parasites, viruses and Mad cow (prions), go to the U.S. Food &Drug Administrations “Bad Bugs Book” on-line at ;

116 116 Bacterial Pathogens Let’s summarize the 4 major pathogens that cause the majority of foodborne illnesses

117 117 Source of Bacteria that cause Foodborne Illnesses Pathogen PathogenCampylobacterSalmonella C. Perfringens Staph. Aureus Source GI tract of mammals, raw milk, untreated water, sewage GI tract, eggs Soil, dust, sewage, GI tract On humans esp nose, hair, face

118 118 Transmission of Bacteria that cause Foodborne Illnesses Pathogen PathogenCampylobacterSalmonella C. Perfringens Staph. Aureus Transmission Contaminated water, raw milk, undercooked meat, poultry or shellfish Raw or undercooked milk, dairy products, eggs, meat, poultry, food handlers “Cafeteria germ”; steam tables or room temp. Person to person contact

119 119 Symptoms of Bacteria that Cause Foodborne Ilnesses Pathogen PathogenCampylobacterSalmonella C. Perfringens Staph. Aureus Symptoms Fever, headache and muscle pain, diarrhea, abdominal pain and nausea 2-5 days after eating Stomach pain, diarrhea, nausea, chills, fever, and headache 8-72 hrs after eating Diarrhea and gas pains 8-24 hrs after eating Nausea, abdominal cramps, vomiting and diarrhea 1-6 hours after eating.

120 120 Prevention of Foodborne Illnesses Although this series presented a lot of information, there are several things we can do to reduce the incidences of foodborne illnesses no matter what type of microorganism we are dealing with.

121 121 Prevention of Foodborne Illness 1)Cook- Cook all meat, poultry and eggs to at least 160F. Other than spore-forming bacteria, all bacteria, parasites and viruses are killed quite easily with heating to 160F. 2)Avoid Cross-Contamination- Do not cross- contaminate one food with another. Keep raw food totally separated from cooked product. Clean utensils and work areas etc in between working raw and cooked product. Constantly be thinking of how microorganisms get from raw to cooked products.

122 122 Prevention of Foodborne Illnesses 3)Chill Foods- Keep foods cold. After cooking, chill foods as rapidly as possible. Remember that cooking has destroyed most of the bacteria but spore formers, that are resistant to cooking may become very active and can proliferate rapidly. 4)Cleaning-Wash fruits and vegetables and all foods possible. In addition, continually wash work areas. Use only treated or tested water.

123 123 Prevention of Foodborne Illnesses 5)Personal Hygiene- People working with foods should wash their hands regularly, wear hairnets, plastic gloves etc. In addition, food handlers should not work with food if they have a boil, open sores or feel sick themselves

124 124 PREVENTION By learning and following the 5 previously mentioned preventive measures, almost all foodborne illnesses can be prevented.

125 125 CONCLUSIONS Although it may appear from the presentation that there are numerous microorganisms that may be in our foods supply, in actuality our food supply is the the safest in the world and at any time in history. Although it may appear from the presentation that there are numerous microorganisms that may be in our foods supply, in actuality our food supply is the the safest in the world and at any time in history. Scientific advances in microbiology and food science have provided knowledge in the control of pathogenic bacteria. Scientific advances in microbiology and food science have provided knowledge in the control of pathogenic bacteria.

126 126 CONCLUSIONS Knowledge of the bacterial control factors (FAT TOM) must be utilized by people in the food processing industry as well as food stores, restaurants and consumers at home to minimize the probability of proliferation of pathogenic bacteria that cause foodborne illnesses. Knowledge of the bacterial control factors (FAT TOM) must be utilized by people in the food processing industry as well as food stores, restaurants and consumers at home to minimize the probability of proliferation of pathogenic bacteria that cause foodborne illnesses.

127 127 CONCLUSIONS By learning and practicing the 5 preventive measures, one can drastically reduce the incidence of foodborne illnesses. By learning and practicing the 5 preventive measures, one can drastically reduce the incidence of foodborne illnesses.

128 128


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