Beta-haemolytic streptococci produce haemolysis when incubated anaerobically. A minority of Group A streptococcus strains will only grow if incubated anaerobically. larger Zones of
Modified Tinsdale medium and tellurite blood agar if diphtheria is suspected.
If in an area where diphtheria occurs or the disease is suspected, inoculate the swab on modified Tinsdale medium and tellurite blood agar.
Incubate the plates aerobically at 35-370c for up to 48 hours, examing for growth after overnight incubation.
Sabouraud agar if thrush is suspected
Inoculate the swab on sabourad agar
Incubate at 35-370c for up to 48hours checking for growth after overnight incubation
Examine the specimen microscopically
Gram smear Examine the smear for pus cells and Vincent’s organisms:
Vincent’s organism are seen as Gram negative spirochaetes