Bacterial Vaccines (lecture)

Question 1

How are vaccines prepared so that they are effective for children under 2?

Answer 1

The polysaccharide is conjugated to a protein.

Question 2

A recently immigrated 8 month old presents with fever, malaise, vomiting, malaise and a cough that ends in a high pitched wine. CBC is increased, with marked increase in lymphocytes. What is the likely causative agent and findings on gram stain? What is required for its growth?

Answer 2

This is likely B. pertussis. It is a gram negative, encapsulated, pleomorphic and short coccobacilli.
The preferred media for growth is charcoal with horse blood (Regan-Lowe).

Question 3

What is the pathophysiology behind increase fluid secretion during pertussis infection?

Answer 3

Pertussis toxin and extracellular adenylate cyclase: incr. cAMP –> incr. excretion

Question 4

6 y.o. South American presents with non specific symptoms and a white psuedomembrane covering his epiglottis and a barking cough. What are your expected results of staining the likely organism?

Answer 4

Diptheria is Gram +, non motile, catalyze + that is grows in a pattern describe as Chinese characters

Question 5

What is the virulence factor of Diphtheria?

Answer 5

Its toxin is responsible for inhibition of protein synthesis