Anaerobic gram positive spore-forming bacilli
Unvaccinated (incompletely vaccinated) individuals with wound (portal of entry).
Note there is no herd immunity as the organism is found in soil/earth and not transmitted person-to-person.
Tetanus: generalized, localized, cephalic, neonatal
Deep wound with necrotic tissue highest risk. See Tetanus Recommendations in SSTI pathway regarding immunoglobulin/Td vaccination.