Gram negative rods Seo

Question 1

Salmonella 2 species

Answer 1

Salmonella bongori
and
Salmonella enterica

Question 2

Members of subspecies I (enterica are associated with…

Answer 2

99% of Salmonella infections in human and warm blooded animals

Question 3

Other subspecies are found in cold blooded animals and he environment except for…

Answer 3

Salmonella arizonae (subspecies IIIa)

Question 4

Where was S. enterica arizonae originally found

Answer 4

in reptiles,

also occurs in fowls and other domestic animals

Question 5

Host for 
S. Typhi
S. Choleraesuis
S. Dublin 
S. Pullorum
S. Gallinarum

Answer 5

humans 
pigs
cattle
poultry 
poultry

Question 6

Common mode of transmission for people

Answer 6

are animals and their products, especially meat and poultry, milk, and pet turtles

Question 7

Since 1975 the FDA has banned what

Answer 7

the sale and distribution of turtles with a shell length of less than 4 inches in size as pets because they are links to Salmonella infections

Question 8

Salmonella disease two major forms

Answer 8

enteritis and septicemia (typhoid)

Question 9

Major signs of enteritis

Answer 9

fever, anorexia, depression, and foul smelling, watery diarrhea that often contain fibrin, mucus, and blood

Question 10

Septicemia may lead to

Answer 10

pneumonia, meningitis, and polyarthritis in the young and agalactia and abortion in adults

Question 11

disease in horses

Answer 11

S. Typhimurium most common, S. Anatum also common
Clinical signs: acute colitis and profuse diarrhea, sometimes abdominal pain, febrile, highly contagious, adults susceptible, colic, GI surgery, and antimicrobial therapy predispose, in neonates septicemia can occur

Question 12

disease in humans

Answer 12

Enteritis: Typhimurium, Enteritidis and Newport

Systemic disease: Typhi

Question 13

Disease in cattle

Answer 13

Typhimurium, Dublin, and Newport
Clinical signs:
4-6 week old calve most common, causes diarrhea with blood and fever, Sometimes septicemia can occur. Septicemia caused by Dublin can cause pneumonia in calves

Question 14

disease in pigs

Answer 14

Typhimurium (enterocolitis) and Choleraesuis (septicemia)

Most common in weaned pigs less than 5 months old

Question 15

disease in chickens

Answer 15

a. Parathyroid-motile Salmonella (anything but Pullorum or Gallinarum)
b. Pullorum disease-S. Pullorum
c. Fowl typhoid-S. Gallinarium

Question 16

S. Typhimurium, and S. Enteritidis infect….

Answer 16

a wide range of animals (poultry, cattle, pigs) and humans, usually causing self-limited enteritis

Question 17

Host adapted S. Typhi causes…

Answer 17

systemic illness in humans (typhoid)

Question 18

Salmonella carriers

Answer 18

are a major source of infections

Question 19

Virulence factors

Answer 19

Type III secretion systems and effector proteins

Capsule-not antiphagocytic, but protect from complement

Question 20

Pathogenesis

Answer 20

a. Oral route to the intestines
b. associated with enterocytes-mediated by fimbriae, M cells are the primary target
c. Invasion of enterocytes by receptor mediated endocytosis. Type III secretion system (needle like projection)
d. Bacterial proteins disrupt enterocyte function and cause release of cytokines (IL 8), which recruits neutrophils that invade and transcytose to intestinal lumen.
e. Neutrophils release prostaglandins causing adenylate cyclase activity in intestinal cells, increased cAMP, disrupts sodium chloride pumpls
f. Diarrhea is secretory and exudative WITHOUT enterotoxin production (similar to EHEC).
g. Some bacteria can transcytose to lamina propria and persist there or be phagocytosed by professional phagocytes and persist there to set up latent carrier state

Question 21

Pathogenesis of systemic infection

Answer 21

Salmonella that persist in professional phagocytes are protected from antibody and can spread to cause systemic infection, particularly with host adapted serovars ( s. typhi in humans- typhoid fever)
-Survives in special Salmonella modified vacuoles that fail to fuse with lysosomes

Question 22

Vaccines and antibiotic treatment

Answer 22

Live vaccines provide the best protection against challenge
-stimulate CMI

Controversy on antibiotic treatment

Question 23

Lab Diagnosis

Answer 23

Most and non-lactose fermenters (exception is S. arizonae group)

Question 24

Salmonella enterica arizonae

Answer 24

• rare in animals except reptiles, chicks, and turkey poults

- Causes an acute septicemic disease of young turkey poults known as arizonosis

Question 25

Klebsiella

Answer 25

• Pneumonia and pyosepticemia in foals

- mastitis in cows (coliform mastitis)

Question 26

Enterobacter-Serratia

Answer 26

(often lumped with Klebsiella as KES group

-Mastitis in cows (coliform)