15 Salmonella

D.A. Salmon in 1885

Genus salmonella is named after?

Genus salmonella is Isolated and described as the “hog cholera bacillus” (Salmonella cholerasuis)

Genus salmonella is Isolated and described as the “____ _____ _____” (Salmonella cholerasuis)

Salmonella cholerasuis

type species of salmonella

2000

how manu serovar in Genus Salmonella?

1. Typical salmonellae

2. Atypical salmonellae

3. S. arizonae and related organisms

4. S. houtinae and related organisms

5. S. houtinae and related organisms S. bongor and related organisms

Classification of salmonella

S. cholerasuis, S. enteritidis, S. gallinarum, S. typhi, S. typhimurium

Examples under typical salmonella

Salmonella salamae

Example under atypical salmonella

• Salmonella cholerasuis

• Salmonella dublin

Salmonellae named after the disease they produce or from animal or place in which they are isolated

Salmonella morphology

• Gram (-) microorganisms

• Non-capsulated short rods

• Peritrichous flagella with fimbriae

• S. gallinarum and S. pullorum (non-flagellated)

Salmonella morphology

• Gram (_) microorganisms

• Non-_____ short ___

• ____ flagella with ____

• Salmonella gallinarum

• Salmonella pullorum

non flagellated salmonella species

Salmonella Cultural Characteristics

• Aerobic and facultative anaerobic organisms

• Grown in BGA, MacConkey agar, bismuth sulfite agar

• • Small colonies 1-4mm

Salmonella Cultural Characteristics

• _____ and facultative _____ organisms

• Grown in ____, MacConkey agar, _____ sulfite agar

• • _____ colonies 1-4mm

Salmonella Cultural Characteristics

• Selective tetrathionate and sodium selenite

• Grows at 37’C as well as 43’C

• • Produces gas from glucose but lactose not fermented

Salmonella Cultural Characteristics

• Selective _____ and sodium ____

• Grows at __’C as well as __’C

• Produces ___ from glucose but ___ not fermented

Phage typing in Salmonella

• Based on sensitivity of culture to series of bacteriophages at appropriate dilutions

Phage typing in Salmonella

• Based on ______ of culture to series of ________ at appropriate dilutions

O, H and Vi

Antigens in Salmonella

Specificity of O antigen determined by structure and composition of the polysaccharide of the cell wall and O antigens designated by Arabic number like 1, 5 or 7

Specificity of O antigen determined by _____ and composition of the _______ of the cell wall and O antigens designated by Arabic number like _ , _ or _

O antigens may change following lysogeny and result in change of serotype

O antigens may change following _____ and result in change of ____

Variation in O antigen can change the colony variation from smooth (S) to rough ® which can result to loss of O antigen and sometimes virulence

Variation in O antigen can change the ____ variation from ____ (S) to + ® which can result to loss of O antigen and sometimes virulence

H antigen heat labile and made up of protein -> exist either as single (monophasic) or two separate forms (diphasic), only one is expressed at a given time -> only FljB (locked ON) or FljC (locked OFF) ->phenomenon known as phase of Andrewes

H antigen ___ labile and made up of _____ -> exist either as single (_____) or two separate forms (_______), only one is expressed at a given time -> only FljB (locked ON) or FljC (locked OFF) ->phenomenon known as phase of Andrewes

phase of Andrewes

this phenomenon occurs in H antigen

Antigens of phase 1 assigned lower case letters and those of phase 2 are given Arabic numbers or lower case letters

Antigens of phase 1 assigned ____ case letters and those of phase 2 are given _____ numbers or _____ case letters

Ags of phase 1 and 2 are determined by genes H1 and H2 which code for flagellar protein flagelli

Ags of phase 1 and 2 are determined by genes __ and __ which code for flagellar protein _____

Salmonella typhi

Vi antigen is found only in this species and the cause of typhoid in humans

feco oral route

Most important mode of transmission is?

primary source: contaminated feed

subsequent: feco-oral route or from egg to chick in the hatchery 

In poultry, whjat are the primary source of infection and subsequent means of spread?

in poultry, once infected, remain carrier and shed the organism intermittently in feces or sometime in milk

in poultry, once infected, remain carrier and shed the organism intermittently in _____ or sometime in ____

Salmonella typhimurium

species that is universally distributed?

• S. abortus equi

• S. abortus ovis

• S. cholerasuis

• S. dublin

• S. gallinarum

• S. paratyphi (A, C)

• S. pullorum

• S. typhi

AACDGPPTT

host adapted salmonellae

• S. anatum

• S. derby

• S. newport

• S. tennessee

• S. typhimurium

ADNTT

non host adapted salmonellae

Host adapted serotypes rarely cause diseases in hosts other than the one to which they are adapted

____ _______ serotypes rarely cause diseases in hosts other than the one to which they are adapted

young animals

who are more susceptible to salmonellosis, younger or older ones?

Poor sanitation, overcrowding, inclement weather

predisposing factors of salmonellosis

wild birds and rodents

salmonellosis sources of infection

Salmonellae killed at 56’C for 10 to 20 minutes except S. senftenberg

Salmonellae killed at __’C for 10 to 20 minutes except S. _________

Salmonellosis starts as enteric infection then reaches the bloodstream

Salmonellosis starts as _____ infection then reaches the ______

Phases of pathogenesis in Salmonella

Phase 1: Colonization of the intestine

Phase 2. Invasion of the intestinal epithelium

Phase 3. Stimulation of fluid exsorption

CIS

Phases of pathogenesis in Salmonella

Colonization of distal small intestine and colon

Phase 1: Colonization of the intestine

first step in pathogenesis?

Phase 1: Colonization of the intestine

Indigenous fusiform bacteria in the epithelium of the large intestine inhibit growth of salmonella by producing volatile organic acid, normal flora blocks attachment sites needed by salmonella

Phase 1: Colonization of the intestine

Indigenous ______ bacteria in the epithelium of the large intestine inhibit growth of salmonella by producing _____ ______ acid, normal flora blocks attachment sites needed by salmonella

Phase 1: Colonization of the intestine

Antibiotic therapy, diet and water deprivation disrupt normal flora increasing susceptibility of host

Phase 1: Colonization of the intestine

______ therapy, ____ and water _____ disrupt normal flora increasing susceptibility of host

Phase 1: Colonization of the intestine

Reduced peristalsis predisposes intestines to colonization

Phase 1: Colonization of the intestine

Reduced _______ predisposes intestines to _______

Peristalsis stimulated by active indigenous microflora

Phase 1: Colonization of the intestine

Peristalsis stimulated by active _______ microflora

Phase 2. Invasion of the intestinal epithelium

• Brush border penetrated, salmonellae enter the cell

• Multiply, enter lamina propria, multiply, phagocytosed and trapped in regional lymph nodes

• Villous tips contract and invaded by neutrophils

Phase 2. Invasion of the intestinal epithelium

• _____ ______ penetrated, salmonellae enter the cell

• ______, enter lamina propria, multiply, phagocytosed and trapped in regional _____ _____

• _____ tips contract and invaded by _____

inflammatory response

Phase 3. Stimulation of fluid exsorption

important factor?

Phase 3. Stimulation of fluid exsorption

Prostaglandins activate adenylate cyclase -> net secretion of water, carbonate, and chloride into the intestinal lumen

Phase 3. Stimulation of fluid exsorption

________ activate adenylate cyclase -> net secretion of water, carbonate, and chloride into the ________ lumen

Phase 3. Stimulation of fluid exsorption

Release of vasoactive substances increase permeability of mucosal vasculature that lead to fluid exsorption

Phase 3. Stimulation of fluid exsorption

Release of _______ substances increase _______ of mucosal vasculature that lead to fluid ______

Phase 3. Stimulation of fluid exsorption

• Enterotoxin similar to E. coli LT enterotoxin produced by some salmonellae strains

Phase 3. Stimulation of fluid exsorption

• Enterotoxin similar to E. coli __ enterotoxin produced by some _______ strains

Phase 3. Stimulation of fluid exsorption

Fluid exsorption accompanied by extensive neutrophil invasion of villous cores with acute ileitis and colitis

Phase 3. Stimulation of fluid exsorption

Fluid exsorption accompanied by extensive neutrophil invasion of villous cores with acute _____ and ______

Phase 3. Stimulation of fluid exsorption

• Neutrophils shed in feces, presence of diagnostic value

Phase 3. Stimulation of fluid exsorption

• Neutrophils shed in ____, presence of diagnostic value

endotoxin released from bacterial cell wall

Phase 3. Stimulation of fluid exsorption

Pathogenesis of salmonella septicemia closely related to effects of?

Phase 3. Stimulation of fluid exsorption

• Endotoxic activity associated with lipid A component of the cell wall lipopolysaccharide

Phase 3. Stimulation of fluid exsorption

• Endotoxic activity associated with ____ ___ component of the cell wall ________

Phase 3. Stimulation of fluid exsorption

Effects include

• fever,

• hemorrhages associated with consumption of coagulation factors,

• leukopenia followed by leukocytosis,

• hypotension and shock that is often fatal,

• depletion of liver glycogen resulting the hypoglycemia

Phase 3. Stimulation of fluid exsorption

Effects include

• _____,

• _______ associated with consumption of _______ factors,

• leukopenia followed by ______,

• hypotension and shock that is often fatal,

• depletion of liver glycogen resulting the hypoglycemia

Phase 3. Stimulation of fluid exsorption

Effects include

• fever,

• hemorrhages associated with consumption of coagulation factors,

• leukopenia followed by leukocytosis,

• hypotension and shock that is often fatal,

• depletion of liver glycogen resulting the hypoglycemia

Phase 3. Stimulation of fluid exsorption

Effects include

• fever,

• hemorrhages associated with consumption of coagulation factors,

• ________ followed by leukocytosis,

• _______ and _____ that is often fatal,

• depletion of liver glycogen resulting the _______

• most important is S. dublin and S. typhimurium

salmonella disease in cattle

Salmonella dublin

salmonella disease in cattle that is host adapted

Salmonella typhimurium

salmonella disease in cattle that is thorughout the world

carrier animals

main reservoir in salmonella cattle diseases

Normal adult cows serve as source of infection for their calves

_____ ______ cows serve as source of infection for their calves

Salmonella pullorum and Salmonella gallinarum

salmonella disease in poultry

Bacillary white diarrhea and fowl typhoid

Common name of

Salmonella pullorum and Salmonella gallinarum

In avian, calves, swine, dogs, humans

S. pullorum and S. gallinarum can also occur in?

Salmonelle pullorum

Disease in poultry that is highly fatal to young chicks during first few days of life

Salmonella pullorum

Salmonella dosease in poultry that isTransmission is transovarial

In salmonella pullorum, Infected eggs may fail to hatch or hatch into infected chicks which if stressed may become ill with diarrhea and septicemia

In salmonella pullorum, Infected eggs may fail to _____ or hatch into infected chicks which if stressed may become ill with ____ and _____

Salmonella pullorum

Salmonella dosease in poultry that is Transmission via incubator -> inhalation

Salmonella pullorum

Salmonella disease in poultry where Chicks huddle near heat source, do not eat, appear sleepy, have diarrhea and die within a few hour

Salmonella pullorum

Salmonella disease in poultry where meningoencephalitis occur

Salmonella pullorum

Salmonella disease in poultry that causes Caseous areas in lungs, gizzard and heart muscle

Salmonella gallinarum

Fowl typhoid in chickens and turkeys

Salmonella gallinarum

Cross-reacts with S. pullorum

• vertical

• horizontal through feces, broken eggs and by tick Argas persicus

transmission in Salmonella gallinarum?

Salmonella gallinarum

Salmonella disease in poultry that Affects adult birds?

• Weakness,

• drowsiness,

• wing drooping,

• hyperexcitability,

• paresis,

• diarrhea

Salmonella gallinarum c/s

Salmonella gallinarum

Salmonella disease in poultry where Rapidly developing anemia and leukocytosis

Salmonella gallinarum

Salmonella disease in poultry where birds found dead, hemorrhages in subcutis and parenchymatous organs, multiple small necrosis in liver and heart and enlarged spleen

Salmonella typhimurium

paratyphoid

Salmonella typhimurium

Salmonella disease in poultry where there is Enteritis, diarrhea and septicemia

Salmonella typhimurium

This can localize in ovaries and be transmitted via the egg

Salmonella typhimurium

Salmonella disease in poultry where it is Common in squabs, die soon after hatching or develop swollen wing joints and unable to fly (megrims) -> gelatinous exudate in joint capsule

Salmonella typhimurium

almonella disease in poultry which cause Infection in the ovary

1. Cell mediated but facultative intracellular parasite

2. Live salmonella vaccines, attenuated, bacterins (Humoral abs directed against O antigens)

Salmonella immunity

Serology: agglutination test, antiglobulin test, ELISA

Salmonella diagnosis

UPDATES: Salmonella species

1. Salmonella bongori

2. Salmonella enterica (formerly cholerasuis)

UPDATES: Salmonella species

1. Salmonella _______

2. Salmonella ________ (formerly cholerasuis)

1. enterica

2. salamae

3. arizonae

4. diarizonae

5. houtenae

6. indica

ESADHI

Salmonella enterica subspecies