How is tetanus spread?

Answer 1

A bacterium called Clostridium Tetani.

It's a gram negative, anaerobic, endospore-forming bacillus which produces a powerful neurotoxin, which causes the symptoms known as Tetanus.

The organism is found in soil, animal faeces and, occasionally, human faeces. Spores are often deposited in dead (oxygen-free) tissue through a wound, burn, or ulcer. The lesion of infection often goes unnoticed allowing spores to germinate and spread long before treatment can be obtained. By secreting a powerful neurotoxin, tetanospasmin, C. tetani blocks the release of neurotransmitters from the presynaptic membranes of inhibitory nerve synapses. The toxin can be up to 10% of the bacterial weight.

Answer 2

Tetanus is not contageous. You catch it by having the infection enter your body through a wound. Not from someone who has it.