Gram Negatives

enterobacteriaceae

family of gram-negative facultative anaerobic rods

coliforms

associated with GI tract of warm-blooded animals and ruminants and can be used as an indicator for potential fecal contamination

cattle

reservoir for E. coli

poultry, cattle, pigs

reservoir for salmonella

humans (dirty hands)

reservoir of shigella

pigs

reservoir of yersinia

aquatic environment 

reservoir of vibrio

soil (feces from contaminated animal)

reservoir of campylobacter

cattle

reservoir of brucella

campylobacter

causes most illnesses

salmonella

causes most deaths

pseudomonas, non-pathogenic e. coli, animal pathogens

non-pathogens

e. coli

resides normally in GI tract of humans and warm-blooded animals

ETEC

e. coli that causes diarrhea in infants and traveler’s diarrhea

humans

what is the primary reservoir for ETEC

in small intestine

where does ETEC colonize

EHEC

produces Shiga toxin

O157:H7

primary serotype of EHEC

O26, O45, O103, O111, O121, O145

big 6 for EHEC

shiga toxin

EHEC produces 

STEC (hemorrhagic colitis)

e. coli that causes severe abdominal cramps, diarrhea, some vomiting, low-grade or absent fever

HUS or TTP

Hemorrhagic Colitis can result in

HUS

STEC can cause this in younger populations, when the shiga toxin targets glomerulus, resulting in renal failure and hemolytic anemia

TTP

STEC can cause this in elderly populations

50%

mortalitity rateof TTP

animals and humans

reservoir of STEC

ground beef, fresh produce, water, petting zoos, childcare

common sources of STEC

type III secretion

pathogenicity of e. coli

salmonella

leading cause of BACTERIAL foodborne illness

invasive infection

salmonella causes…

temperature and pH

salmonella enterica is resilient and adaptive to changes in

meat, poultry, fish, produce, low moisture foods

sources of salmonella enterica

s. typhi and paratyphi

causes enteric fever

non-typhoidal salmonella

most consequential in the US

beef and poultry, LMFs, and produce

salmonella outbreaks

Shigella

what is similar in relatedness to E. coli (EIEC) and Salmonella

humans

reservoir for shigella

bloody diarrhea, abdominal/rectal pain, cramps, fever

symptoms of shigellosis

T3SS

invasive shigella involves

pseudotuberculosis

yersinia that can sometimes pass to humans

pestis

yersinia that is the cause of the plague, 

entercolitica

yersinia that is a primary foodborne pathogen

psychotrophic

yersinia temperature requirement

fever, abdominal pain, diarrhea

symptoms of yersinia

microaerophile

oxygen requirements campylobacter

animals, shellfish

reservoir for campylobacter

2-5 days

onset for campylobacter

fever, abdominal cramps, diarrhea

campylobacter symptoms

cholerae, parahaemolyticus, vulnificus

3 types of vibrio

NaCl

what is vibrio tolerant of

serogroup O1

vibrio from contaminated water/seafood

non-O1

vibrio cholerae from shellfish from warm waters

gastroenteritis

caused by vibrio parahaemolyticus

4-96 hours

onset of gastroenteritis

halophiloc

vibrio parahaemolyticus is…meaning it requires salt to grow

parahaemolyticus

most common type of vibrio case in the US

vulnificus

most common type of death associated with Vibrio in the US

cattle, sheep’s and goats, and pigs

reservoir of brucella

3 weeks

incubation period of brucella

undercooked meat and unpasteurized dairy 

sources of brucella