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ANTHRACOID BACILLUS. Some bacilli other than B.anthracis may occasionally cause human infections B.cereus – Septicemia, endocarditis, pneumonia, meningitis, wound infections and other suppurative lesions B.subtilis, B.licheniformis have also been isolated PSEUDOANTHRAX. ANTHRAX BACILLUS. - PowerPoint PPT Presentation
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ANTHRACOID BACILLUS
• Some bacilli other than B.anthracis may occasionally cause human infections
• B.cereus – Septicemia, endocarditis, pneumonia, meningitis, wound infections and other suppurative lesions
• B.subtilis, B.licheniformis have also been isolated
• PSEUDOANTHRAX
ANTHRAX BACILLUS
• Non-motile• Capsulated• Grow in long chains• Medusa head
colonies• No growth in
penicillin agar• Haemolysis is absent• Slow liquefaction
ANTHRACOID BACILLUS • Motile• Non capsulated• Grow in short chains• Not present
• Grows usually
• Usually well marked• Rapid liquefaction
• No turbidity in broth• Salicin fermentation
negative• No growth at 45oC• Growth inhibited by
chloral hydrate• Susceptible to
gamma phage• Pathogenic to lab
animals
•Turbidity usual
•Usually positive
•Grows usually•Not inhibited
•Not susceptible
•Not pathogenic
• B.thuringiensis
• B.subtilis
• B.coagulans
• B.steatothermophilus
• B.licheniformis
BACILLUS CEREUS
• Large gram positive bacilli
• Widely distributed in nature
• Generally motile
• Non capsulated
• Large grey irregular anthracoid colonies
• Haemolytic
About….
•M’Fadyean’s reaction negative
•Ferments glucose but not mannitol
•Not susceptible to gamma phage
•Anthrax flouroscent antibody conjugate
•Animal pathogenicity test
• Food poisoning is a common, usually mild, but sometimes deadly illness.
PATHOGENESIS
source : contaminated food
route : ingestion
INGESTION
DIARRHOEAL SYNDROME
EMETIC SYNDROME
• EMETIC TOXIN HBL• DIARRHOEAL TOXIN Nhe Cyt k
B.cereus spores and vegetative cells
Rice pulses Various foods
Spore survives cooking
Organism ingested
Heat labile enterotoxin
DIARRHOEA
Spores survive cooking
Enterotoxin in food not destroyed by heating
Enterotoxin ingested
VOMITING
Diarrhoeal syndrome Emetic syndrome
Infective dose 105–107 (total) 105–108 (cells g−1)
Toxin producedIn the small intestine of the host
Preformed in foods
Type of toxin Protein Cyclic peptideIncubation period 8–16 h 1–5 h
Duration of illness 12–24 h 6–24 h
SymptomsAbdominal pain, watery diarrhoea and occasionally nausea
Nausea, vomiting and malaise
Foods most frequently implicated
Meat products, soups, vegetables, puddings/sauces, milk/milk products
Fried and cooked rice, pasta, pastry and noodles
Lab diagnosis• Specimens : stool sample vomitus food sample
MYPA medium for isolation from feces
TREATMENT
• Short lived and self limiting• Antibiotic not indicated• Gentamycin, vancomycin, ciprofloxocin-bacteremia in immunosuppressed patient
Preventive measures
FOOD POISONINGWHAT???
HOW???
WHEN???
Single source outbreak are becoming larger with modern food processing and
distribution
CAUSES
IMPROPER COOKING
IMPROPER STORAGE TEMPERATURES
TEMP NOT SUFFICIENT TO KILL THE SPORES
FOOD POISONING
INFECTIOUS AGENTS
TOXIC AGENTS
• SYMPTOMS -nausea -vomiting -diarrhoea -fever, chills, -bloody stools, dehydration, nervous
system damage
ETIOLOGY % OF CASES
TYPICAL INCUBATION PERIOD
PRIMARY CLINICAL FEATURES
CHARACTERISTIC FOODS
BACILLUS CEREUS
1-2 1-6 hrs Vomiting, diarrhoea Rice, meat, vegetables
CLOSTRIDIUM BOTULINUM
5-15 12-72hrs Neuromuscular paralysis
Improperly preserved vegetables, meat, fish
STAPHYLOCOCCUS AUREUS
5-25 2-4hrs vomitings Meat, custard salad
CHEMICALS 20-25 1-48hrs variable _
ETIOLOGY % OF CASES
TYPICAL INCUBATION PERIOD
PRIMARY CLINICAL FEATURES
CHARECTERISTIC FOODS
CLOSTIRIDIUM PERFRINGENS
5-15 4-15hrs Watery diarrhoea Meat, poultry
SALMONELLA 10-30 6-48hrs dysentery Meat, poultry, eggs
SHIGELLA 2-5 12-48hrs dysentery variable
VIBRIO PARAHEMOLYTICUS
1-2 10-24hrs Watery diarrhoea Shell fish
LAB
DIAGNOSIS
TREATMENTGENERALLY NOT REQUIRED
REQUIRED WHEN????
PROPHYLAXIS