Food Poisoning 1x PDF

FOOD POISINING Etiology of food poisoning Infectious Bacterial Viral Biotoxin Chemical Insecticide, heavy metal  FOOD POISINING Consumption of contaminated food with pathogenic microorganisms, their toxins or chemicals 2/3 of food-borne outbreaks; due to ba...

FOOD POISINING Etiology of food poisoning Infectious Bacterial Viral Biotoxin Chemical Insecticide, heavy metal  FOOD POISINING Consumption of contaminated food with pathogenic microorganisms, their toxins or chemicals 2/3 of food-borne outbreaks; due to bacteria  Food-borne outbreaks Two or more persons experience smilar illnes (gastrointestinal) after ingestion a common food Epidemiologic analysis implicates food as the source of the illness ( 60°C, any longer than necessary keep raw and cooked food separate keep kitchen and utensils clean wash and dry your hands properly cover any cuts or sores when handling food Intoxications due to toxin preformed in the food S.aureus (99%) B.cereus C.botulinum  Bacillus cereus an agent of food poisoning two types of food-borne intoxications "short-incubation" or emetic form "long-incubation" or diarrheal form In either type, the illness usually lasts less than 24 hours after onset.  emetic form 1 characterized by nausea and vomiting and abdominal cramps Clinical symptoms and course are like S. aureus incubation period 1 to 6 hours caused by a heat-stable enterotoxin the mechanism and site of action of this toxin are unknown  emetic form 2 most often associated with fried rice after cooked to held food at warm temperatures for several hours diagnosed by the isolation of B.cereus from the incriminated food  B.cereus diarrheal form 1 incubation period of 8 to 16 hours abdominal cramps and diarrhea small volume or profuse and watery diarrhea benign, self-limited illness, antibiotics are not necessary  B.cereus diarrheal form 2 mediated by a heat-labile enterotoxin activates intestinal adenylate cyclase, causes intestinal fluid secretion associated with meat or vegetable- containing foods diarrheal form is diagnosed by isolation of the organism from stool and food Intoxications due to toxin preformed in the food S.aureus (99%) B.cereus C.botulinum  Clostridium Botulinum present in soil, water, sewage or on plants Under anaerobic conditions- *germination, *synthesizes and *releases a potent exotoxin.  botulinum toxins the most potent toxins known 1g can kill 1 million people eight antigenically distinct toxins: A, B, C ( ), C ( ), D, E, F, and G. each strain produces a single toxin type Types A, B, E, and (rarely) F cause human disease Toxins A and B are the most potent food-borne botulism 1 Spores present in food Spores germinate in anaerobic conditions Toxin is released into food If not destroyed by heating, toxin is ingested, absorbed in gut, enters bloodstream  food-borne botulism 2 attaches to presynaptic terminals of cholinergic nerves blocks neurotransmitter release, nerve impulses cannot be transmitted muscles connected to nerves not stimulated Result: generalized flaccid paralysis Food-borne botulism3 Symptoms · appear within 18-36 hours post ingestion · dose dependent · the severity of the illness varies from mild to severe, · death can occur within 24 hours Mortality rate: type A 75%, others 20%  Symptoms weakness double vision, dizziness blurred vision, dilation of pupils, dryness of mouth nausea, vomiting inability to swallow difficult speech, respiratory paralysis  Prevention of Botulism Canning or preserving foods with appropriate heat, pressure, & low pH – Spores Survive 2 hr at 100 °C Inactivated at 120 °C Boiling food before canning at high elevations may not inactivate the spores Factors favoring spore germination: Low acidity (pH > 5.0); Low O2; High water content – Toxin: Inactivated after 1 minute at 85 °C, or 5 minutes at 80 °C Avoid exposure of infants to honey (may contain Clostridium botulinum spores) Immunization – Pentavalent toxoid – Used only for high risk personnel: Laboratory workers and military  Prevention, C.botulinum keep hot food hot and cold food cold ≤5 and > 60°C, any longer than necessary bottle only high acid fruits at home add citric acid to tomatoes, melons and tropical fruits bottle vegetables in vinegar,  Intoxications due to toxins manufactereed in the body After live organisms are ingested C.perfringens V.cholerae Enterotoxigenic E. Coli (ETEC)  Clostridium perfringens Spore formation allows to survive harsh environment Rapid growth in vivo Many toxins produced (more than 20)  Serotypes of C. perfringens (A-E) according to the kinds and proportions of exotoxins produced Type Alpha Beta Epsilon Iota A X B X X X C X X D X X  C. perfringens the "food poisoning strains" belong to Type A self limited gastroenteritis incubation period of 8 - 12 hours following ingestion of a heavily contaminated food nausea, vomiting, cramps, diarrhea  C. perfringens contamination of a meat product cooking kills vegetative cells, not spores during improper cooling, spores germinate, vegetative cells multiply ingestion followed by sporulation in GI tract, release of enterotoxin Prevention: C.perfringens , B. cereus keep hot food hot and cold food cold ≤5 and > 60°C cool food quickly after cooking if you want to store it Divide large volumes of food into small portion reheating food to steaming hot (75°C) before eating, stir the food to make sure all parts are heated through  Lab Work up Microscopic examination of stool * Methylene blue staining- WBC (differentiates invasive/ non-invasive) * Wet –mount, Iodine solution for ova and parasites  Patients Food Handler Etiology Food stoo vomitus blood stool Nose Hand l S.aureus C C C,T C C C.botulinum C,T C,T T C,T B.cereus C C C C.perfringens C,T C C: culture, T: Toxin, Conclusion  Prevention Infants Older persons Susceptible Pregnant immunocompromised Never consume raw fish, raw seafood, raw meat  Therapy Most: self limited Supportive measures (fluid replacement) Antiperistaltic drugs contraindicated  Common Inc. Toxin Duration Symptom vehicle period s B.cereus Fried rice 1- 6 h. STNeuroT 4-6 h V, C, D Meat balls 6-14 h. LT 24 h Vegetables C.perfringens Beef, 8-22 h LT 24 h D, C poultry C.botulinum Home- 18-24 Neuro Death Flaccid canned food h toxin due to paralysis Honey respirat. (infant) failure S.aureus Ham, poultry 1-6 h ST 24 h V, C, D Cream pasty (Neuro T) Egg salads  Etiology Season Geographic predilection S.aureus Summer None B.cereus Year round None C.botulinum Summer, fall Developing c. C. perfringens Fall,winter, None spring thanks for your attention