Commonly known as food poisoning, foodborne illness is caused by eating food that is contaminated by bacteria or other harmful substances.
How does food become hazardous?
Food becomes hazardous by contamination. Contamination is the unintended presence of harmful substances or microorganisms in food. Food can become contaminated from:
Chemical hazards
Physical hazards
Biological hazards
What is “cross contamination?”
Cross-contamination is the transportation of harmful substances to food by:
Food Safety Overview Organisms History Epidemiology Transmission Foodborne illness Prevention and Control Organisms Estimated 250 foodborne pathogens 2 or more cases of a similar illness resulting from ingestion of a common food Bacteria most common cause Also viruses, parasites, natural and manufactured chemicals, and toxins from organisms Foodborne disease outbreaks, cases and deaths 1993-1997 Salmonella had the highest number History Early 1900’s Contaminated food, milk and water caused many foodborne illnesses Sanitary revolution Sewage and water treatment Hand-washing, sanitation Pasteurization of milk- 1908 Refrigeration in homes- 1913 History Animals identified as a source of foodborne pathogens Improved animal care and feeding Improved carcass processing Surveillance and research Outbreak investigations Laws and policies regarding food handling Epidemiology Foodborne diseases each year in US Affects 1 in 4 Americans 76 million illnesses 325,000 hospitalizations 5,000 deaths 1,500 of those deaths caused by Salmonella, Listeria, and Toxoplasma Epidemiology Many unrecognized or unreported Mild disease undetected Same pathogens in water and person to person Emerging pathogens unidentifiable Greatest risk Elderly Children Immunocompromised Surveillance/Regulation Surveillance CDC FoodNet and PulseNet Regulation FDA Domestic and imported food USDA FSIS Meat, eggs, poultry National Marine Fisheries Service Surveillance FoodNet: Active surveillance Established 1996 CDC, USDA, FDA, select state health departments Nine sites in U.S. monitor 13% of U.S. population California, Colorado, Connecticut, Georgia, Maryland, Minnesota, New York, Oregon, Tennessee Surveillance PulseNet: Identify cause Molecular fingerprinting 45 state public health labs certified Passive surveillance: Survey methods Hospital discharges Outpatient treatment facilities FoodBorne Disease Outbreak Surveillance System All states submit outbreak data Estimated Cost Economic Research Service – USDA Cost of top 5 foodborne pathogens $6.9 billion annually Medical cost Productivity losses (missed work) Value estimate of premature death Transmission Oral route Contamination varies Organism, reservoir, handling/processing, cross-contamination Human reservoir Norwalk-like virus, Campylobacter, Shigella Animal reservoir Campylobacter, Salmonella, E. coli 0157:H7, Listeria, and Toxoplasma Transmission Contamination can occur at several points along the food chain On the farm or in the field At the slaughter plant During processing At the point of sale In the home Produce Processing Important Organisms Norwalk-like viruses Campylobacter Salmonella E. coli O157:H7 Clostridium botulinum Shigella spp Toxoplasma Emerging organisms Norwalk-like Viruses Norovirus; Caliciviridae family Most common foodborne agent 23 million cases annually Sources Person-to-person Shed in human feces, vomitus Outbreaks in daycares, nursing homes, cruise ships Contaminated shellfish Norwalk-like Viruses Small infectious dose Signs 12-48 hours post-exposure Nausea, vomiting, diarrhea, abdominal cramps Headache, low-grade fever Duration: 2 days Food handlers should not return to work for 3 days after symptoms subside Campylobacter jejuni Leading cause of bacterial diarrhea 2.4 million people each year Children under 5 years old Young adults (ages 15-29) Very few deaths Can lead to Guillain-Barré Syndrome Leading cause of acute paralysis Develops 2-4 weeks after Campylobacter infection (after diarrheal signs disappear) Campylobacteriosis Sources Raw or undercooked poultry Non-chlorinated water Raw milk Infected animal or human feces Poultry, cattle, puppies, kittens, pet birds Clinical signs Diarrhea, abdominal cramps, fever, nausea Duration: 2-5 days Salmonellosis Gram negative bacteria Many serotypes can cause disease S. enteritidis and typhimurium 41% of all human cases Most common species in U.S. 1.4 million cases annually 580 deaths Salmonellosis Sources Raw poultry and eggs Raw milk Raw beef Unwashed fruit, alfalfa sprouts Reptile pets: Snakes, turtles, lizards Signs Onset: 12-72 hours Diarrhea, fever, cramps Duration: 4-7 days E. coli O157:H7 Enterohemorrhagic Escherichia coli (EHEC) Surface proteins; toxin Sources Undercooked or raw hamburger; salami Alfalfa sprouts; lettuce Unpasteurized milk, apple juice or cider Well water Animals: Cattle, other mammals E. coli O157:H7 Signs Watery or bloody diarrhea, nausea, cramps Onset: 2-5 days Duration: 5-10 days Sequela Hemolytic Uremic Syndrome (HUS) Acute kidney failure in children Life threatening Botulism Clostridium botulinum Neurotoxin leads to flaccid paralysis Infants at greatest risk Annually: 10-30 outbreaks; ~110 cases Sources: Home-canned foods, honey Signs Double vision, drooping eyelids, difficulty speaking and swallowing Onset: 18-36 hours Shigellosis Bacillary dysentery Most cases Shigella sonnei 90,000 cases every year in U.S. Sources: Human fecal contamination of food, beverages, vegetables, water Signs: Watery or bloody diarrhea, nausea, vomiting, cramps, fever Onset: 2 days Duration: 5-7 days Toxoplasmosis Toxoplasma gondii- intracellular protozoan 112,500 cases annually Pregnant women/immunocompromised at greatest risk Sources Infected cats, soil, undercooked meat Signs Fever, headache, swollen lymph nodes Emerging Pathogens Cyclospora (Protozoan) 1996, imported raspberries Listeria monocytogenes Sources Ready-to-eat meats, soft cheeses Signs Human abortions and stillbirths Septicemia in young or low-immune Prevention and Control HACCP Hazard Analysis Critical Control Point To monitor and control production processes Identify food safety hazards and critical control points Production, processing and marketing Establish limits Monitor Applied to meat, poultry, and eggs On Farm Strategies Testing and removal for Salmonella Serologic, fecal culture, hide culture Vaccinating Many serotypes Varying effectiveness Minimize rodents, wild birds Isolation of new animals At the Slaughter Plant FSIS target organisms Salmonella and E. coli Control points Removal of internal organs Minimize contact between carcasses Proper movement through facilities Chilling Cooking processes (time, temperature) Irradiation Used since 1986 for Trichina control in pork Gamma rays Poultry in 1990/1992 Meat in 1997/1999 Reduction of bacterial pathogens Kills living cells of organisms Damaged and cannot survive Irradiation Identified with radura….. Does not affect taste quality Nutrients remain the same Handle foods appropriately afterwards Does not sterilize Contamination can still occur USDA Recall Classification In the Home Drink pasteurized milk and juices Wash hands carefully and frequently After using the bathroom Changing infant’s diapers Cleaning up animal feces Wash hands before preparing food In the Home Wash raw fruits and vegetables before eating After contact with raw meat or poultry Wash hands, utensils and kitchen surfaces Hot soapy water Defrost meats in the refrigerator In the Home Cook beef/beef products thoroughly Internal temperature of 160oF Cook poultry and eggs thoroughly Internal temperature of 170-180oF Eat cooked food promptly Refrigerate leftovers within 2 hours after cooking Store in shallow containers Additional Resources Centers for Disease Control and Prevention http://www.cdc.gov/foodsafety/ U.S. Department of Agriculture http://www.foodsafety.gov http://fnic.nal.usda.gov/about-fnic Acknowledgments Acknowledgments
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