Midterm 2

Question 1

Special culture media for corynebacteria?

Answer 1

Clauberg medium (K- tellurit medium) – selective differential medium for isolation of c. diphtheria. Contains potassium –tellurite and blood glycerinate. Organisms that grow on this culture medium reduce potassium tellurite to tellurium; resulting in black to greyish colonies, and garlic smell.

Question 2

zoonosis (definition, examples)?

Answer 2

Definition:

an infection or parasite shared in nature by humans and other animals that are normal or usual host, the disease of humans is acquired from an animal source. Or

An infectious disease transmissible under natural conditions between vertebrate animals and human beings. Animal to human spread. Rodents, mammalians are the natural hosts. Direct contact, food and vector bite.

Examples:

Brucella genus (b. bovis, b. melitensis, b. suis, b.canis)

Francisella tularensis (antropo-zoonosis)

Question 3

8. Lancefield grouping

Question 4

Eosin methylene blue medium:

Question 5

CAMP test

Question 6

5. Indol test

Answer 6

E. coli is indol positive

Procedure: triptophane -à indole via triptophanase enzyme

Put the bacteria in a triphosphate solution add indol reagent (amylalcohol = organic material, when bacteria procedure indol, it is dissolved in reagent which is organic and therefore lighter than water positive result intense red circle on top.

Question 7

4. List 4 major meningitis pathogens!

Answer 7

N. Meningitidis

Haemophilus influnzae

E. coli (nosocomial, newborns)

Streptococcus agalactiae (no. 1 in newborns)

Question 8

3. List 4 viral vaccines! (What is the content? Against which disease?)

Answer 8

IPV (poliomyelitis virus, content: inactivated virus given at 2,3 in 18 months + 6 years)

MMR – mumps, morbilli, rubella , live attenuated viruses (15 months, 11 years)

Question 9

2. Morphology of Bacillus cereus (culture, microscope)

Answer 9

gram +, rod, spore forming , gram stain blue , beta haemolytic – blood agar

cloud like colonies under microscope