General Characteristics of Streptococcus :

1.     Streptococcus:

General  Characteristics of Streptococcus :      

a. Gram Positive coccus.

b. Arranged in short chain or long chain,

c. Spherical or oval in shape,

d. About 1 µm in diameter,

e.   Many are facultative anaerobes.

f. Grow better in enriched media,

g. Non-flagellated , non-sporing, non-motile, usually

non-capsulated but one more virulent,

h. Catalase negative,

Habitat:

a. Found on the skin and inside the naso-pharynx, mouth and throat in small numbers ,

b. In Pyogenic lesions,

c. Rectum.

Diseases Produced by Streptococcus :

a.      Pyogenic diseases:

i)                   Respiratory tract:

● Cellulitis

Figure : Streptococcus

●Tonsilitis

●Pharyngitis

●Peritonsillar abscess

ii)                Skin & soft tissue:

●Erysipelas

●Impetigo

●Pyoderma

                                                                                  

iii)              Ear infection:

●Otitis media                                                    

●Mastoiditis

                                                                                 

iv)               Genital tract:                                                       

●Puerperal sepsis

v)                  Deep infection:

●Lymphangitis

●Acute endocarditis

● Septicaemia

b)Toxigenic diseases:

i)                   Scarlet fever,

ii)                Toxic shock syndrome

c) Immunogenic diseases/post streptococcal disease:

i)                   Acute rheumatic fever (ARF),

ii)                Acute glomerulonephritis (AGN),