Characteristics of specific food-born pathogens Flashcards
What is the most common Yersinia spp involved in food born disease
Yersinia enterocolitica
Describe the characteristics of Y. entero
gram - fac anaero rod 1-44 degrees survival 5-7%NaCl pH-4-5
What animal is Y. entero most common source
Pig
What are the clincial signs of Yersiniosis
acute fever and G-enteritis
bloody d+
hepatic absesses
incubation = 1-11d
How can Yersinia get into food
poor evisceration
its a psychotroph so can live a -5-20+
inadeq pasteurisation
describe the main characteristics of vibrio cholera
fac anaerobe halophiles alkaliphillic rod grows in water! inc = 6hours!
what are the symptoms of cholera toxicoinfection
watery d++++++
abdo pain
dehydratin
shock
what are the major differences of vibrio parahaemolyticus and cholera?
invasive infection,
produces haemolytic toxin in enterocytes
milder symptoms
What is the identifying symptom of vibrio vulnificus from cholera?
necrotic skin lesions
What are the main sources of listeria monocytogenes
GIT
soil, water, plants
forms persistent biofilms - work surfaces!
What are the main characteristics of INVASIVE listeriosis?
invasive infection
incubation = 1-20d
systemic invasion
immuno-comp people commonly
What are the main characteristics of NON-INVASIVE listeriosis?
d+ and headache
incub = 1-3d
healthy individuals mostly
what is the average minimum toxic dose for bacteria toxins?
10^6
What are the characteristics of staffy a?
fac anaerobe resistant to desiccation and thermophile survives 100! most common toxins = A and D incub = 1-6hrs
What are the maj symptoms of the staff a
V+D
abdo pain
NO fever
dehydrat
how to prevent a staffy a infection - since you cant really kill it
cook and eat fast
little handling as pos
hope below infective dose
what are the main characteristics of Cl botulinum
spores
anaerob
neuro toxin -> paralysis
what are the 2 forms of cl bot infection
intoxication (botulinum)
toxico-inf (infants)
what are the prote-olytic toxins formed by clost bot?
A, B, F
What are the main bacillus cereus
gram + spore rod D+V syndromes V - onset 1-14hrs; D - onset 4-16hrs
B cereus is very thermophillic; how long and at what temp is req to kill it (enough)
15m at 100 degrees
What are the main characteristics of clot perfringens
type A toxin - in GIT and soil
spore
what are the main charact of rotavirus
ds RNA
winter vom disease commonly
profuse/projectile V+D!
What are the main characteristics of calcivirus
ssRNA like norovirus winter vom (like rotavirus) V+D adults more effected than children
What are the main characteristics of Hep A
ssRNA high shedd ing in faeces rare in UK vaccination V+D virus in GIT --> liver jaundice!
What are the main characteristics of Hep E
RNA
pork!
mild usually
