Nelson - Ch. 194 H. influenza

Question 1

H influenza ? Gram staining ? shape

Answer 1

Gram neg, pleomorphic coccobacillus

Question 2

Requirements of H influenza for growth

Answer 2

Factor X (hematin), Factor V (phosphopyridine nucleotide)

Question 3

H influenzae ? capsule

Answer 3

Yes, serotyped in 6 distinct types designated a,b,c,d,e,f

Question 4

T/F Humans are the only natural hosts of H. influenzae

Answer 4

T

Question 5

T/F H influenza is part of the normal respiratory flora of healthy children

Answer 5

T, in 60-90% of healthy children

Question 6

T/F Asymptomatic colonization with H influenzae type b occurs at a much lower rate in immunized populations

Answer 6

T

Question 7

Socioeconomic factors for invasive G. influenzae type b disease

Answer 7

1) Childcare outside the home 2) Siblings of elementary school age or younger 3) Short duration of breastfeeding 4) Parental smoking

Question 8

In Hib infection, history of ___ is associated with risk for invasive disease

Answer 8

Otitis media