World wide in distribution in the soil and in animal feces
Longer and thinner gram-positive rods with round terminal spores giving characteristic “drum-stick” appearance.
There are ten antigenic types of c. tetani but all produce the same neurotoxin.
The toxin has two components:
Tetanospasmin: Neurotoxic property
Tetanolysin: Hemolytic property
Pathogenesis and Clinical manifestation:
Infection of devitalized tissue (wound, burn, injury, umblical stamp, surgical suture) by spores of C.tetani Germination of the spore and development of vegetative organism Neurotoxin release from vegetative cells The toxin binds to receptors on the presynaptic membrane of motor neuron the retrograde axonal transport to the spinalcord and brain
Inhibition of inhibitory glycinergic and GABAergic
secreting neurons hyperreflexia
Spatic paralysis, muscle spasms and
IP= 4-5 days to several wks Tetanus classical presentation: . Lock jaw or trismus . Arched back or opistotonus . Arm flexion and of leg extension . Fever and sweating