Enteric pathogens Flashcards
(25 cards)
What is the main pathogen causing foodborne illness in the UK?
Campylobacter
What culture material is usually used to isolate enteric pathogens?
MacConkey agar - contains bile salts
How does E. coli appear on MacConkeys agar?
Ferments lactose forming pink/ red colonies
How does Salmonella appear on MacConkeys agar?
Does not ferment lactose and therefore agar does not change
Brilliant green again is selective for what bacteria?
Salmonella - colour change from yellow to red
EMB media is selective for what bacteria?
E.coli
Which media is used to isolate Campylobacter?
Blood based agar - CCDA/ Skirrows. Reduced O2 tension
How does phage typing work?
Bacteria are tested against a panel of bacteriophages
What definitive methodology is used to type bacteria?
Genome sequencing
EPEC
Entero pathogenic E. coli
ETEC
Entero toxigenic
EIEC
Entero Invasiv
EHEC
Entero Haemorrhagic
EAEC
Entero Aggregative
UPEC E. coli is associated with what antigen and pathology?
Urinary tract infection (UPEC) allow attachment to
urethra or bladder.
Pili & Fimbriae enteric forms and UPEC to allow attachment
LPS is associated with what E.coli pathology?
Septicaemia
Which virulence factor is associated with ETEC?
Enterotoxin
What virulence factor is responsible for gut attachment and invasion of EPEC and EHEC?
T3 secretion system
Verotoxin and Shiga-like toxins cause what pathology?
Target blood vessels and causing bloody diarrhoea (gut) and haemolytic uremic syndrome (kidney)
Salmonella is most commonly found in which foodstuffs?
Eggs and meat
Foodstuffs contaminated with faeces from infected animals
Salmonella species associated with non-typhoidal salmonellosis
Enteritidis
Typhimurium
Incubation period of non-typhoidal salmonellosis.
12-72 hours
Sudden onset of painful abdominal cramps, followed by fever, headache, diarrheoa (sometimes bloody) and vomiting. Symptoms lasting 5 days.
What pathogen may be suspected?
Salmonella
Which phage type of Salmonella is most commonly found in the UK?
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