Usually, the bacterial toxins enter the body through a break in the skin caused by an object contaminated with tetanus. If you have one or more of the following injuries or wounds that are prone to tetanus, you should get a tetanus booster shot. These include:  Any wound visibly contaminated with soil, dust, or horse manure. Puncture wounds. Objects that can cause these types of wounds include wood splinters, nails, needles, glass, and human or animal bites.  Skin burns. Second degree (partial-thickness or with blisters) and third degree (full-thickness) burns are at higher risk for infection than first degree (superficial) burns.  Crush injuries that damage tissue by squeezing it between two heavy objects. They can also happen when heavy objects are dropped onto parts of the body.  Wounds involving necrotic, or dead, tissue. This kind of tissue has no blood supply, increasing its risk for infection (along with severely compromised tissue). For example, areas of gangrene (dead body tissue) are at increased risk for infection.  Wounds with foreign objects in them. Wounds that have foreign bodies, such as splinters, glass shards, gravel, or other objects in them are at higher risk for infection. If you never received the first series of tetanus shots (primary vaccination series) or you're not sure when you had your last tetanus shot, you should go get a tetanus shot. If you've been injured, you may be wondering whether you need to get a tetanus booster shot. You will need a tetanus booster shot if:  Your wound was caused by a “clean” object, but your last tetanus shot was over 10 years ago. Your wound was caused by a “dirty” object and your last tetanus shot more than 5 years ago. You're not sure if the wound was caused by a “clean” or “dirty” object and your last tetanus shot was over 5 years ago. In order to help transfer tetanus antibodies to your baby, you should get a tetanus vaccine when you are between 27-36 weeks pregnant.  Your doctor will likely recommend the inactivated Tdap (Tetanus, Diptheria and...

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Write a summary of the previous text in Chinese:
受了某些伤后，必须打破伤风预防针。 知道是否该打预防针了。 怀孕时打预防针。 让自己免疫。