Foodborne Dz: Bacterial Flashcards
What bacterial foodborne illnesses do not colonize the intestinal tract, or replicate in the body?
Intoxication only
Bacteria replicates in food and produces a toxin within that food
A foodborn illness caused by a bacterial infection will colonize in the _________
GI tract
What bacteria associated with foodborne illnesses are infectious via intoxication?
Staph aureus
Bacillus cereus
Clostridium botulinum
Clostridium perfringens
Bacterial toxins are named by _____ and by target ______
Type and target tissue
What bacteria produce exotoxins? What bacteria produce endotoxins?
Gram positive = Exo
Gram negative = endo
When will you see signs associated with bacterial intoxication? What is the usual duration?
Onset is usually rapid: 30min - 6hr most commonly (up to 12hrs)
Duration is usually 1-2 days
Botulism toxin is an exception
When will you see signs associated with a bacterial infection from food? How long do they last and what are they?
Onset = several hours to days
Illness usually lasts for several days
Many produce enterotoxins that cause watery dhr: ranging from mild to severe
Invasive species or species with toxins that kill enterocytes cause dysentery, fever, and possible septicemia **dehydration
What temperature range is considered the food danger zone?
40-140F
What is the reservoir of staph aureus?
Skin and nose of (many healthy) people
How is staph aureus transmitted?
Vehicle: food - contaminated with S. aureus and stored at temps good for growth and toxin production
What is the most common foodborne intoxication?
S. aureus
What is the incubation time of S. aureus and the duration of intoxication?
30mins - 6 hours
Duration = +/- 24 hours
What clinical signs are associated with S. aureus intoxication?
Vomiting, dhr, cramping
How is S. aureus prevented?
Proper food hygiene and proper food storage (temp is important!!)
Bacillus cereus is a gram _____, soil dwelling, rod shaped, spore forming bacterium
POSITIVE
reservoir = soil
aka “fried rice syndrome”
How is bacillus cereus transmitted?
Vehicle = food. Contaminated with bacteria or spores and stored at temps good for growth and toxin production
T/F: Bacillus cereus is killed via cooking
FALSE
What are the two forms of Bacillus cereus intoxication and what are the associated clinical signs?
- Enteric form = Nausea/vomiting. Incubation is 30min to 6hr
- Diarrhea form = diarrhea and cramping. Incubation period 8-16 hours
How is Bacillus cereus prevented?
Proper food hygiene
Proper food storage (temp)
What is the reservoir of clostridium botulinum?
Soil; sediments (stream, lake, and coastal); intestinal tracts of fish and mammmals; gills and viscera of crabs/shellfish; honey
What is the mode of transmission of C. botulinum?
Vehicle: Food contaminated with spores at production and then improperly processed allowing growth and toxin production
C. botulinum is mostly associated with what preservation process of foods?
Canning
What is the time frame of clinical onset of C. botulinum intoxication?
18 - 36 hours
up to 8 days
What are the clinical signs associated with Botulism?
Typically will start with ocular signs - blurred vision, double vision, drooping eyes. Then a descending paralysis
What food should be avoided in infants less than 12 months?
Honey
Can contain C. botulinum spores that are able to sporulate within the GI tract of infants
If a patient is suspected to have Botulism, does treatment begin before lab test results are completed?
YES