The bacteria that cause tetanus are found in soil, animal faeces and sometimes in human faeces. The bacteria can cause a tetanus infection if they enter your body through a wound or a cut. You are most likely to develop an infection if you have a wound that was caused by something dirty such as a knife or nail, or an animal bite. Babies can get neonatal tetanus via a healing umbilical wound that hasn't been cleaned properly or that has been cut with an instrument that isn't sterile.
Attribution: BUPA