Which is the principal virulence factor in C. tetani?

Tetanospasmin referred to as tetanus toxin, is the neurotoxin that causes the manifestations of tetanusClostridium tetani:General characteristicsCultural characteristics--Strict anaerobe, gram-positive bacilli--Stately motility--Spherical terminal spores--Drumstick appearance--Swarming growth --Blood agar - a hemolysis - b hemolysis Virulence factors Clinical features--Tetanospasmin (neurotoxin), Tetanolysin (hemolysin)--Generalized tetanus --Risus sardonicus, Opisthotonus, Respiratory muscle spasm--Trismus - first sign--Neonatal tetanus - 8th day diseaseDiagnosisTreatment--Direct culture of unheated material on blood agar incubated anaerobically --DOC - Penicillin or Metronidazole--Alternative - Clindamycin or Erythromycin --Mainstay of treatment - AntitoxinProphylaxisPrevention--Active immunization - Antitoxin>0.01 IU/ml serum--Passive immunization - Human tetanus Immunoglobulin7 cleans - Clean hand, Clean surface, Clean cord blade, Clean cord tie, Clean cord stump, Clean towel, Clean waterRef: Ananthanarayan 9th edition, p564-569