Tetanus infection can be fatal. Tetanus bacillus is an anaerobic bacterium and infection is usually caused by trauma, if the wound is deep or if the wound has not been properly sterilized and the wound is tightly capped. After infection, the tetanus bacillus will multiply in the body and the incubation period is 3-21 days. Tetanus bacillus will release tetanus toxin, which is a very toxic neurotoxin, it will cause muscle spasms in the human body, and the patient will show a horny and bitter smile, and even cause spasms in the respiratory muscles, resulting in respiratory difficulties, or even lead to asphyxiation and death.