Salmonella Flashcards
Salmonella description
Motile, Most are Lactose fermenters, produce H2S, gram negative, small rods
Salmonella 2 species
S. bongori (many serovars) & S. enterica (many subspecies)
Salmonella - Antigenic composition
O antigen (LPS) and H antigen (flagella)
Salmonella adhesins
Fimbria/pili - attach M cells - Pef, Agf or curli and long polar fimbra Lpf
Salmonella Pathogenicity islands
Effector proteins mediate uptake, ruffle formation, intra-macrophage survival, death of activated macrophages, unknown functions
Salmonella Pathogenicity island types
Secreted proteins - Outer proteins- system effectors - system apparatus - Magnesium transport
Salmonella reservoir
GI tract of animals, ubiquitous geographically & zoologically - Normal flora prevent disease
Salmonella pathogenesis
Adherence to M cell/Epithelial cell–> injection of effectors & internalization–> replication & cell death –> chemokine release (inflammation–> hemorrhagic diarrhea) –> dissemination maybe, septicemia
Salmonella in ruminants
Feedlots! Young & adults - Intestinal & deptic presentation (pneumonia & abortion, osteomyelitis/Joint ill)
Salmonella species in cattle
S. dublin (pneumonia in calves), S. typhimurium, S. newport
Salmonella species in sheep
S. typhimurium, S. abortus ovi
Salmonella in Swine
Hog Cholera bacillus DDx=classical swine fever
When I say hog cholera, you say…
Salmonella!
Salmonella in horses
Common in adults, diarrhea - GI tract surgeries/colic/antimicrobial tx predisposes them
Salmonella in dogs/cats
Carriers - outbreaks from contaminated food or treats
Salmonella in poultry! 4 main diseases
Paratyphoid - Pullorum - Fowl typhoid - Avian arizonosis
Salmonella - Paratyphoid disease
S. enteridis & typhimurium - High losses first 2 wks old - Survivors=asymptomatic shedders - Ingestion/fecal contamination - Button type lesions on small intestine
If you see button-type lesions on SI, you say…
Paratyphoid disease! S. enteridis & typhimurium
Pullorum diseases
Non-motile Pullorum - Bacillary white diarrhea - Grey nodules in heart, lung, liver
When you see white diarrhea and grey nodules in heart, lung, liver, you think…
Pullorum diseases! Salmonella
Fowl Typhoid
S. gallinarum - Similar to pullorum but in adults too - REPORTABLE in USA
Salmonella in humans
Foodborne zoonoses - infection depends on dose, serotype, immune status - Typhoid Fever from Typhoid Mary - Gastroenteritis - Septicemia
Typhoid fever in humans, you say…
Salmonella infection!
Salmonella Immunity
Normal flora compete - Opsonins & anti-adhesins - Activated macrophages/PMN/ NKCs - Vaccinaiton (challenging)
Salmonella Selective media
Lactose fermentors! Produce H2S! So: MacConkey agar, Brilliant Green agar, Xylose Lysine agar, HE agar, Eosin methylene blue, TSI —-etc
