Three and a half year old babies who have been injured by rusty iron should be vaccinated against tetanus if there is an obvious open wound, but not if there is no open wound. Tetanus bacillus is usually found in soil contaminated with feces, rusty metal or iron, and is an anaerobic bacteria. Tetanus bacillus may be present in rusty iron, so if your baby has been smashed and has a large, deep wound, he or she should be vaccinated against tetanus, but if there is no open wound after the smash, no tetanus vaccine is needed. Infection with tetanus bacillus can cause muscle spasms, respiratory paralysis and respiratory failure. Three-year-old baby smashed should pay attention to the wound to avoid water, ensure hygiene of the affected area, to avoid bacterial infection caused by inflammation. When the baby smashed seriously, should go to the hospital in time for examination and treatment.