Brief Answer:
Discussed below.

Detailed Answer:
Hello.
Welcome to HCM.
Thank you for the query.

Tetanus , commonly called as "Lock jaw" is caused by a bacteria called Clostridium Tetani. Infection usually occurs by contaminated wound.
Usually patients presents with prodromal symptoms like Fever, malaise, weakness, tiredness.
Gradually patient presents with neck stiffness, sweating, painful muscle contraction, muscle around mouth get contracted and patient finds it very difficult to open mouth. It looks as if patient is widely smiling all the time with difficukty in opening mouth, which gives it the name "Lock jaw".
Tetanus is one of vaccine preventable diseases.

Hope I have explained it.

Regards.

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