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Gram-positive cocci and Gram-negative cocci-KH

John L. Bezzant,M.D.

This shows Gram-positive (purple/blue) cocci, and a scattering of Gram-negative (red) cocci. The organism that most commonly infects the skin is staphylococcus aureus, and the younger organisms stain Gram-positive, and the older organisms are sometimes Gram-negative.