Issues of food-borne diseases/illnesses

1. Issues of food-borne diseases/illnesses Issues of food-borne diseases/illnesses Microbes & Toxins

2. Prepared by Winfried Scheewe, DED, Marketing c#onsultant to CEDAC for the “Complying with market requirements on Food Safety and Product Quality”Second Regional Training WorkshopLinking Small Farmers to Markets January 19-23, 2009 Siem Reap, Cambodia

3. Food-borne illness • term used to describe the adverse health effects associated with the consumption of • biological,(including parasites) • chemical and • physical hazards in food. More than 200 diseases are spread through food

4. Food-borne illness • Each day millions of people become ill and thousands die from a preventable food-borne disease • WHO estimate: Worldwide 5 – 10% of the population suffer from food-borne illnesses annually Food-borne diseases are increasing worldwide

5. Cambodia • Cambodia: High incidence of deaths due to diarrhoeal diseases • can be attributed to contaminated water and food • WHO: Children under 5 years: • 17% of deaths due to diarrhea All age groups: • 7% of deaths due to diarrhea

6. Cambodia (2) • Food-borne illnesses are one factor contributing to the low life expectancy(2004 data)

7. Transmitted + originating from food We can distinguish: • Diseases transmitted through food: • Hepatitis A • Typhoid fever • Cholera, etc. • Diseases originating from the food: • Spoilage • Infected animals

8. Food Poisoning • Most food-borne diseases food poisoning • any condition in which a food causes a toxic reaction • Generally:affecting the stomach and intestines = gastrointestinal disease resulting from bacterial (or sometimes viral) contamination of foods

9. Food Poisoning • Other causes: • fungal spoilage mycotoxins • a toxin naturally present in the food • pesticide residues • contamination with industrial chemicals • a toxin acquired by the food as a result of • natural accident (such as contamination • of fish or shellfish by ‘red tide’)

10. Bacterial Food Poisoning • contamination of foods with bacteria that do not cause any obvious spoilage, • food is still apparently fit to eat, • but may contain hazar-dous amounts of harmful organisms or toxins

11. Bacterial Food Poisoning (2) or • sufficient numbers of bacteria to cause an infection • Some bacteria already have infected the animal or plant

12. The symptoms poisoning range from mild diarrhea, through severe diarrhea and vomiting, to potentially life-threatening illness. In some cases the symptoms develop within a few hours of eating the contaminated food Symptoms • in other cases there may be a delay of several days, or even weeks, before there are any signs of infection

13. Food-poisoning Organisms • With most food-poisoning organisms, an intake of several thousand is required for infection, • but consumption of as few as 10 of the virulent entero-haemorrhagic E.coli strain 0157 can cause life-threatening illness.

14. Causes Of Food Poisoning • The way animals are raised + crops cultivated • The way in which the food is handled and prepared • esp. lack offood hygiene + personal hygiene • Inadequate cooking of contaminated raw food (under-cooking) Bacillus cereus: causes the "Fried Rice Syndrome"

15. Causes ... (2) • Inadequate reheating • Keeping cooked food at temperatures that favor the growth of bacteria • Cross-contamination between raw and cooked food • Poor personal hygiene in food handlers

16. Major food-borne illnesses • Salmonellosis • Campylo-bacteriosis • E.coli infection, esp. E.coli O157 • Listeriosis • Cholera (WHO ranking) Special case: Botulism

17. Salmonellosis • Transmitted through contaminated poultry, eggs, and certain other foods • Also found on citrus fruits • Causes abdominal pain, fever, nausea and vomiting, and diarrhea • Incubation period is 8 to 48 hours, and an attack may last from three to seven days

18. Salmonella • Usually destroyed by adequate cooking • Some types can lead to typhoid fever • The bacteria survives in dried food

19. Campylobacter jejuni • probably most common bacterial cause of gastroenteritis worldwide • incidence of human campylobacter infections has been steadily increasing Gastroenteritis inflammation of the lining membrane of the stomach and the intestines characterized especially by nausea, vomiting, diarrhea, and cramps

20. Campylobacter jejuni • Bacteria, which is naturally part of the intestinal microflora • Cannot be treated with antibiotics • Can be caused by cross-contamination during food preparation

21. Campylobacteriosis • Most people who become ill develop diarrhea, • cramping, abdominal pain and fever • Symptoms: anywhere from 2 to 5 days after consuming a contaminated food

22. Campylobacteriosis • Poultry (raw chicken) is recognized as the primary pathway • other sources include unpasteurized milk and non-chlorinated water • common in cattle, pigs and other animals

23. Control of Campylobacter • Aim: to develop strategies to control campylobacter in the food supply "from farm to fork" • campylobacter can be reduced: natural feed ingredients (additive) caprylic acid naturally found in coconut and breast milk  antifungal and antibacterial properties

24. Escherichia coli Infection • Some 5 million E. coli bacteria normally inhabit intestinal tract • Vital to processing vitamins in the diet • Several strains are pathogenic and cause gastroenteritis • Strain E. coli 0157:H7potentially fatal form of food poisoning

25. E. coli 0157:H7 • Outbreaks in the US linked to spinach and other leafy vegetables • E.coli 0157:H7 probably originates from cattle

26. Botulism • Caused by a toxin produced by the bacteria Clostridium botulinum • especially dangerous because a large number of people can be poisoned by eating a batch of contaminated food • derived from the soil, grows in many meats and vegetables • Develops in anaerobe conditions such as canned food

27. Avoidance Spoilage or decomposition can be delayed: • Observance of hygiene • Storage in high salt or sugar concentrations or in weak acids (pickling); • Drying (desiccation) or cooling (refrigeration); and Killing the micro-organisms by heat (canning and pasteurization)

28. Food contamination throughTOXINS • Mycotoxins are produced by fungi, commonly known as mold. These toxins can develop during production, harvesting, or storage of grains, nuts, and other crops. • Mycotoxins are among the most potent mutagenic and carcino-genic substances known

29. Mycotoxins • They pose chronic health risks: • prolonged exposure through diet has been linked to cancer and kidney, liver, and immune-system disease • Mycotoxins occur more frequently under tropical conditions Many diets consists heavily of food from crops susceptible to mycotoxins

30. Aflatoxins • naturally occurring mycotoxins, produced by many species of the fungus Aspergillus, • Aflatoxins are highly toxic and cause cancer • After entering the body, aflatoxins are metabolized by the liver

31. Aflatoxins • Discovered after in 1960, mold-conta-minated peanut meal was shipped from Brazil to England • caused of the death of more than 100,000 turkey • Cause: liver damage

32. Avoidance of mycotoxins • Improved post-harvest practices • Proper storage • Shift from cereal based to pasture based feeding (instead of feedlots) • Free-range poultry

33. Unknown burden commonly only a part of the cases are reported  less than 10 percent

34. Common Problems • Indices of food-borne illnesses tend to increase • Often the pathogens cannot properly be identified ( up to 80% of cases) • Resistance against antibiotics increasing ( drug-resistant Salmonella)

35. Problems (3) • Refridgertion can preserve the food but also preserve many harmful organisms • Globalization of food supply  widely dispersed outbreaks • Often slow response by authorities

36. The looming climate change will probably worsen some problems: Higher temperature and moisture Outlook • More flooding and extended droughts  polluted water • may lead to new problems with food-borne diseases

37. Conclusion • In view of the rapid genetic adaptability we could say: • “Microorganisms are opponents with whom we cannot race on their terms”(Dr. Lederberg) We only can try to avoid conditions in which harmful microbes can develop

38. Thank you!