DMF Week 7 SAQ

1

Which one or more of the following statements is correct?

The transcutaneous route of viral infection of humans is exemplified by:

A - papilloma viruses which enter the skin via abrasions

B - hepatitis A virus which enters via use of contaminated needles

C - hepatitis B virus which can enter via body piercing and tattooing

D - dengue virus which is spread by the bite of a racoon


2

Which one or moreof the following statements about interferons is correct?

A - Interferons are of type I and type II which bind to the same receptor

B - Type II interferons (IFNgamma) are produced by T cells and NK cells

C - Type I interferons (IFNalpha and beta) are produced by NK cells

D - Type I interferons (IFNalpha and beta) activate NK cells


3

Which one of the following statements about the ability of viruses to cause damage to host cells and thus disease is incorrect?


4

Which one of the following statements about the herpes virus family is incorrect?


5

Baby S.T. is three days old and is in the neonatal unit, having been born at 32 weeks gestation after a prolonged labour. She weighs 2.1kg. She has become irritable, is feeding poorly and has become hypoxic. A paediatrician collects blood and CSF for culture. Which one or more of the organisms listed below is a likely cause of this baby’s illness?

A - Streptococcus agalactiae

B - Listeria monocytogenes

C - E. coli

D - Neisseria meningitidis


6

The organism grown from blood cultures is a Gram negative bacillus, which grows on MacConkey agar as a large (2 – 3mm diameter) lactose fermenting colony.

On the basis of the above results, which one of the organisms listed below is a likely cause of this baby’s illness?


7

Which one of the statements below regarding the agents which cause congenital and perinatal infections is correct?