Summary Streptococci spp: A Complete Laboratory Guide to Classification and Diagnosis.

CHAPTER TWO
PART-I
Streptococci spp


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, Outcomes of this lecture
Recognize and understand the following:
 Morphology
 Culture
 Classification
 Pathogenesis
 Diseases
 Laboratory diagnosis
 Treatment
 Prevension and Control
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, General Characteristics of
Streptococci
 Gram-positive spherical/ovoid cocci arranged in long chains;
commonly in pairs
 Non-spore-forming, nonmotile, can form capsules and slime
layers
 Facultative anaerobes
 Do not form catalase, but have a peroxidase system
 Most parasitic forms are fastidious and require enriched media
such as blood agar for their growth.
 Small, nonpigmented colonies
 Sensitive to drying, heat and disinfectants
 25 species

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, Morphology
 Gram positive cocci
arranged in chain.
 They are non-motile,
non-sporing forming
and some strains
are capsulated.



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