Whether a 3-year-old child bitten by a child should get a tetanus shot depends on the condition of the wound, which may or may not be injected. Normally speaking, if the wound is relatively shallow, it is usually not easy to form an anaerobic environment, and there will be no symptoms of tetanus bacillus parasitism, and of course there is no need to get a tetanus shot. However, if the bite is relatively serious, such as a relatively deep wound, more foreign objects, necrotic tissue residue, etc., it is recommended to clean and disinfect the wound first, and promptly inject tetanus antitoxin or tetanus immunoglobulin. If you can not clarify the wound condition, it is recommended to go to the hospital surgery to give the wound treatment, if necessary, tetanus injection.