Morphology
i)
Shape – It is fairly long , thin and rod shaped
bacillus
ii)
Size – About 8 μin length and 0.5 μ uin breadth .
iii)
Pleomorphism may be found
iv)
Spore – Terminal spores like drum stick are present .
v)
Capsule – It is absent
vi)
Flagella – Weavy peritrichate flagella are present and
so it is motile .
vii)
Gram positive bacillus .
viii)
Non-acid fast bacillus .
Pathogenesis of Clostridium tetani
i)
The toxin liberated by clostridium tetani passes the
nerve cells of the anterior horn cell of the spinal cord by way of axons or
perineural lymphatics of the regional motor nerves and gives rise to tonic
muscular contraction .
ii)
The toxinmay pass into the blood stream and enter into
the central nervous system .
iii)
Incubation period is about 8-days .
iv)
There will be series of tonic muscular contraction
locally and then in general . Due to the tonic muscular contraction there will
be ‘ lock-jaw “ as the muscles of the jaw are frequently affected .
