Salmonella Shigella & Yersinia

Question 0

2 main conditions caused by salmonella

Answer 0

Gastroenteritis

Typhoid fever

Question 1

Is salmonella a true or opportunistic pathogen?

Answer 1

True pathogen

Amongst most successful human pathogens

Question 2

Salmonella strain that causes Typhoid fever?

Answer 2

S. Typhi

Question 3

Symptoms of 1st phase typhoid fever

Answer 3

Slow mild fever

Flat rose spots

Question 4

Reaches gall bladder, with reinvasion of intestine, ulcers, haemorrhage and (20%) death- are symptoms of what disease by s.typhi

Answer 4

2nd phase typhoid fever

Question 5

Which disease does S.Paratyphi cause?

Answer 5

Enteric fever

Similar to typhoid fever, but less severe.

Question 6

Which disease does S.Cholerae cause?

Answer 6

Bacteremia

Blood Infection. High mortality.

Question 7

Can salmonella exist in asymptomatic carriage?

Answer 7

Yes

Question 8

Which bacteria is often spread rapidly in states of sanitation break down (eg natural disasters)

Answer 8

Salmonella causes typhoid fever.

S.Typhi

Question 9

Typhoid fever host specific?

Answer 9

Yes. Human exclusive

S.Typhi and S.Paratyphi

Question 10

Salmonella causing gastroenteritis

Answer 10

S.Typhinurium

S.Enteritidis

Question 11

Symptoms of salmonella gastroenteritis

Answer 11

Abdominal pain. & fever.

But self limiting

Question 12

Dysentery and shigellosis are caused by…?

Answer 12

Shigella

Question 13

What is the infection route for shigella?

Answer 13

Faecal oral transmission

Question 14

What is the natural reservoir for shigella?

Answer 14

Man

Question 15

How infectious is shigella?

Answer 15

Highly infectious

Question 16

What is the most frequent serotype of shigella?

Answer 16

S.Flexneri

Question 17

Which is the most severe serotype of shigella?

Answer 17

S.Dysenteriae

Question 18

Which two types of yersinia cause self limiting gastroenteritis?

Answer 18

Y. Enterocolitica

Y.Pseudotuberculosis

Question 19

Which form of yersinia is ALWAYS imotile?

Answer 19

Yersinia Pestis

Others are motile below 30c

Question 20

Which Yersinia strain causes gastroenteritis without diarrhoea?

Answer 20

Y.Pseudotuberculosis

Likely to become systemic

Question 21

At which temperatures does Y.Enterocolitica grow?

Answer 21

Between -1 +40

Psychotroph

Question 22

What is yersinia Enterocolitica main virulence factor?

Answer 22

Heat stable enterotoxin

INVASIVE PATHOGEN

also pYV virulence plasmid

Question 23

What is a characteristic symptom of yersinia Enterocolitica

Answer 23

Abdominal aim localised to the right side, often mistaken for appendicitis

Question 24

What are the chronic carriers/sources of yersinia Enterocolitica?

Answer 24

PIGS

Raw pork. Unpasteurised milk.

Question 25

In which age group is yersinia Enterocolitica most common?

Answer 25

<7 yrs

Question 26

What is the salvatic cycle?

Answer 26

Cycle of yersinia Pestis within the environment between fleas and rats

Question 27

How does yersinia Pestis enter an urban cycle!

Answer 27

When the sylvatic cycle overlaps- Eg. An urban ratios bitten by a flea carrying y.pestis from rodents In the sylvatic cycle

Question 28

What is the progression of the plague?

Answer 28

Bubonic plague

Septicaemic (Black Plague)

Pneumonic plague

Question 29

In which stage of the plague does yersinia Pestis travel to the lymph nodes?

Answer 29

Bubonic plague

Question 30

What is the impact of a blocked protrenviculous

Answer 30

Prevents fleas receiving nutrients from food, increasing hunger & in turn feeding- further spreading the disease.

Also causes fleas to regurgitate last y.pestis infected meal into new host.

Question 31

What causes the black lesions in plague?

Answer 31

Lysis of bacteria releases LPS causes septic shock producing black lesions

Question 32

How is pneumonic plague transmitted

Answer 32

Via aerosol- highly infectious

Question 33

Which three important groups of gram negative bacteria are NOT enterobacteriacae?

Answer 33

Vibrios

Campylobacter

Helicobacter

Question 34

Which branch of the proteobacteria are the vibrionaceae from

Answer 34

GAMMA

Question 35

What are the differences between enterobacteriacae and vibrionacaea?

Answer 35

SINGLE polar flagellum

Most are oxidase POSITIVE

Most have aquatic habitats