Rough Guide to the Identification of
Bacteria of Medical Importance

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This is a quick guide to the identification of bacteria commonly encountered in clinical diagnostic microbiology laboratories. It does not include reference to important pathogens that are difficult to isolate, for example chlamydia, mycoplasmas and rickettsias, although species in these genera may cause serious disease. It should be noted that a very few simple tests will enable most bacteria in this key to be identified to genus level. Click on the appropriate link to follow your identification to its conclusion...

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The bacterium you are identifying is Gram-positive

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The bacterium you are identifying is Gram-negative

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