FOODBORNE INTOXICATIONS

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FOODBORNE INTOXICATIONS
OCCUR WHEN POISONOUS PLANT OR ANIMAL TISSUES IS
CONSUMED OR FOOD CONTAINS BACTERIAL AND ALGAL
TOXINS OR MYCOTOXINS EXAMPLES OF BACTERIA
PRODUCING TOXINS Clostridium botulinum,
Staphylococcus aureus
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FOODBORNE INFECTIONS
OCCURS WHEN BACTERIA ARE CONSUMED IN FOODS AND
THEN THEY MULTIPLY IN THE INTESTINES AND PRODUCE
ILLNESS. SALMONELLA, CLOSTRIDIUM PERFRINGENS,
LISTERIA MONOCYTOGENES, E. COLI INVASIVE AND
ENTEROTOXIGENIC
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FOODBORNE ILLNESS/INJURY THRESHOLD LEVELS

• SALMONELLA lt 105 CELLS
• Cl. PERFRINGENS 106 CELLS
• BACILLUS CEREUS 106 CELLS
• CAMPYLOBACTERUM 106 CELLS
• VIBRIO CHOLERAE 106 CELLS
• E. COLI 106 CELLS
• YERSINIA 109 CELLS

• STAPHYLOCOCCUS TOXIN
  1 mg
• HEPATITIS VIRUS
  1000? CELLS
• NORWALK VIRUS 10? CELLS

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STAPHYLOCOCCUS AUREUS

• is a facultative anaerobe-can grow in presence
  or absence of oxygen
• can tolerate 10-20 salt and 50-60 sugar
• optimum temperature for growth 35-37 C, but may
  also grow at 7C or even at 47.5C
• enterotoxin is stable under cooking
• Foods commonly associated meat and meat
  products, poultry, fish and fish products, milk
  and dairy products, ice cream, custards, cream
  filled bakery products.

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For Staphylococcal poisoning to occur

• Food must be contaminated with toxin producing
  Staphylococci
• Food must be capable to support the growth
• Food must be held at temperature and time
  sufficient to permit growth and production of
  toxin
• Food must be consumed

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STAPHYLOCOCCAL POISONING
Staphylococcal food intoxication is a second most
prevalent foodborne disease. Growth of millions
or more cells is necessary for sufficient toxin
production to elicit symptoms of food poisoning.
Onset may occur within 30 min to 8 hrs after
ingestion of food containing toxin.Symptoms
nausea, vomiting, cramps, sweating, chills, weak
pulse, shallow respiration, subnormal body
temperature. Recovery usually occurs within 24-48
hrs. S. aureus is commonly found in nose,
throat, hair, skins (hands,fingertips) gt 50
healthy individuals skins and hides of
animals.Source of infections infected wounds
and lesions of food handlers coughing and
sneezing by individuls with respiratory problems.
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Salmonellosis

• accounts for about 40 of all recorded foodborne
  diseases
• usually self limiting acute gastroenteritis
  often misdiagnosed by both patients and
  physicians as intestinal influenza
• the incubation period 6-48hrs (12-36hrs
• symptoms diarrhea, abdominal cramps, vomiting
  and fever. Generally last 1-7 days.
• Associated both with animals both wild and
  domestic
• Food associated beef, turkey, home-made ice
  cream, pork, chicken and raw eggs.

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Salmonellosis-contributing factors to the
implicated foods

• improper cooling
• inadequate cooking
• ingestion of contaminated raw foods
• cross contamination

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Clostridium botulinum

• Sporeforming anaerobic bacteria that produces
  very potent toxin
• Symptoms double vision, inability to swallow,
  speech difficulty, progressive respiratory
  paralysis. Onset after 12-36 hrs or even 8 days.
• Food implicated canned low-acid food, smoked
  fish.

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Listeriosis

• may involved central nervous system- meningitis,
  encephalitis.
• other- stillborn babies, miscarriages
• population at risk the unborn, newborn,
  immunocompromised ( pregnant women, elderly)
• Listeria has ability to grow at refrigerated
  conditions, at pH range of 5-9.5 is salt
  tolerant -survive 100 days in 30 salt solution
  at 4 C

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Foodborne illnesses

• Molds - produce very potent carcinogens
• Parasites (Trichinella spiralis Toxoplasma gondi)

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Prevention of foodborne illness

• Application of heat
• Adequate refrigeration
• Adequate time and storage conditions
• Sanitation
• Safe thawing practices
• Food additives (antimicrobials)

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Effect of temperature

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Food toxicants

• Lectins
• Glucosinolates
• Oxalic acid
• Vitamins antigonists (avidin, thiaminase)