Shigella Sonnei

Question 1

gram stain

Answer 1

gram negative rods

Question 2

media

Answer 2

grows on MacConkey, HE, XLD, and SS

Question 3

Appearance on media

Answer 3

NLF; clear flat colonies with jagged edges on Mac, clear on HE and XLD

Question 4

IMViC

Answer 4

• • • -

Question 5

Lactose fermentation

Answer 5

negative (most strains)

Question 6

H2S production

Answer 6

negative

Question 7

Oxidase

Answer 7

negative

Question 8

Indole

Answer 8

negative

Question 9

Methyl red

Answer 9

positive

Question 10

Voges Proskauer

Answer 10

negative

Question 11

Citrate

Answer 11

negative

Question 12

Motility

Answer 12

negative

Question 13

Unique characteristics

Answer 13

overt pathogen

Question 14

TSI

Answer 14

K/A

Question 15

LIA

Answer 15

K/A

Question 16

Diseases

Answer 16

dysentery defined as acute inflammatory colitis and bloody diarrhea characterized by cramps, tenesmus (feeling of constantly needing to defecate, and bloody, mucoid stools; infections may produce only watery diarrhea; onset in 12-50 hours

Question 17

Reservoirs

Answer 17

only found at times of infection

Question 18

Transmission

Answer 18

person to person spread by fecal-oral route, especially in overcrowded areas and areas with poor sanitary conditions; highly infectious; contaminated water and unsanitary food handlers; infants, elderly and infirm are highly susceptible

Question 19

Vectors

Answer 19

not part of normal bowel flora

Question 20

Serotyping

Answer 20

types O antigens (Groups A, B, C, & D)

Question 21

Endemic areas

Answer 21

300,000 in US per year

Question 22

Specimens

Answer 22

stool

Question 23

Virulence factors

Answer 23

several factors involved to mediate adherence and invasion of mucosal cells, escape from phagocytic vesicles, intercellular spread, and inflammation; Shiga toxin role in disease is uncertain, but it does have various effects on host cells