Food poisoning

1. Food poisoning Dr. Muhabat Raji Images used in this lecture were obtained from various internet websites. Their use is for educational purposes only.

2. Expectations... • Describe • the bacteriology and virulence characteristics of some agents of food poisoning (FP) • the risk factors and clinical presentation FP • Discuss the principle of management • laboratory approaches to the diagnosis of FP

3. Outline • Introduction • Bacteriology of some agents of FP • Pathophysiology of FP • Risk factors for • Laboratory approaches to the diagnosis of FP • Principles of management and recurrence

4. Introduction • FP is a common condition worldwide • May present with self limiting diarrhoea or with diarrhoea associated with vomiting • Ingestion of preformed microbial toxins/chemical toxin in food • Staphylococcus aureus enterotoxin • Bacillus cereus • Ingestion of spores may lead to infection • Clostridium botulinum

5. S. aureus FP • symptoms usually begin within 1 to 6 hours • nausea • vomiting • abdominal cramps • S. aureus toxin is heat-stable • often associated with the consumption of foods prepared by a food handler such as • dairy produce • meats • eggs • salads

6. S. aureus FP

7. S. aureus FP • Diagnosis is clinical • Food remnant or vomitus can be screened for the heat stable enterotoxin. • Culture is not routinely performed • Screen for toxin genes

8. B. cereus • Can also form toxin in starchy food • Rice • Associated with nausea, vomiting and diarrhoea • Onset of symptom within 1 to 6 hours • Diagnosis is clinical • Toxin may be screened for in vomitus/food remnant

9. Bacillus cereus • catalase positive • aerobic (or facultative anaerobic) • spore-forming gram-positive bacilli • diarrheal enterotoxin and the emetic toxin

10. Clostridium botulinum • causes botulism • a rare but potentially life-threatening neuroparalytic syndrome resulting from the action of a neurotoxin • Botulinum toxin is the most potent bacterial toxin

11. Types of botulism • Food borne botulism • Infant botulism • Wound botulism • Adult enteric infectious botulism or adult infectious botulism of unknown source

12. Agents of FP

13. Management • Usually self limiting • Food history • IVF and antibiotics if needed • Take preventive measures

14. Conclusion • FP is usually a self limiting condition • Most case are diagnosed clinically • Presence of toxin is more diagnostic • Food history is important • Supportive care may be needed in some cases.