Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

25 Cards in this Set

  • Front
  • Back
what type of organism is Clostridium perfringens?
Gram (+ve)
Spore forming rod
what food borne illness symptom is it know for worldwide?
Diarrheal disease
what are the symptoms of Tpye A C.perfringens foodborne illness?
Bloating & gas
Profuse diarrhea w/abdominal cramps
little or no vomiting
few cases of fever/headache
what is the incubation period of C.perfringens?
8 - 22 hours
Median = 12hours
Clostridium is known as a "ubiquitous Organism" what does this mean?
It is found everywhere in the environment.
Human reservoir
food vehicle
fly vector
Soil & dust
How many types of C.perfringens are known & what are they?
A, B, C, D, E
what causes illness in Closrtidium perfringens?
the enterotoxin
Do spores give rise to new spores directly?
the answer is no, the spores form vegetative cells which multiply then sporulate into more spores
what is the sequence of events which lead to C.perfringens outbreak?
1)growth of cells in food (germination)
2)food consumed and sporulation occurs in Intestine
3)spores form vegetative cells & divide /& produce toxin
why is reheating considered the last line of defense in preventing C.perfringens outbreak?
the vegetative stage will be killed off.
why are large chunks of meat the food vehicles for C.perfringens outbreaks rather than thin meats such as hamburgers?
takes longer to cool, thus allowing for growth
more anaerobic environment in large chunks of meat.
what laboratory test was developed by the MOH in ontario to ID enterotoxin in faeces?
ELISA test
what are some other Lab diagnostic tests methods to ID C.perfringens as the causitive agent?
1)look at the number of spores in faeces 10*6 spores /gram of faeces

2)10*5 cells of C.P/g of food if available to test
3)serotype same amoung victims
4)match of serotypes in victims faeces & food
what is the Rabbit ileal test?
researchers tool to ID if bacterinm produces an enterotoxin
What are the most common factors contributing to outbreaks of Clostridium perfringens?
Inadequate Storage - 46.1%

Improper heating - 38.5%
what is the optimum temperature range for Clostridium perfringens?
37 - 45 degrees C
NB may double in 8-10 mins @45 C
what temperature is considered normal for C.perfringens growth?
20 - 50 C
what is the best way to kill off C.perfringens?
refrigeration of food source is best way
what is the pH range for growth for C.perfringens?
5.5 - 8.5
What is the Eh for C.perfringens?
will grow b/w -200 and +320mV

prefers negative values

what happens to C.perfringens @ -17.7C?
tends to be preserved at this temperature.
where are the spores of C.perfringens most found?
Muscle & internal Organs of food animals:
How does the enterotoxin exert its action?
breaks down the brush border of the microvilli
resulting in a net flow of water into sm Intestine
giving rise to diarrhea
what are the diagnostic clues for C.perfringins?
Severe lower abdominal pain
Absence of fever & headache
little vomiting , w/nausea sometimes
Incubation period: 8-23 hours
Shortest IP 1 hour
what difference in terms of an outbreak helps to determine whether Samonella is responsible or C.perfringens?
with Samonella the source might be a carrier
but with C.perfringens the problem is inadequate cooling of meat.