Generally, a booster shot of rabies vaccine can be administered for 3 to 6 months. If re-exposure occurs 6 months after the booster shot of rabies vaccine, the vaccine needs to be re-administered. If re-exposure occurs 6 months after a full course of rabies vaccination, 2 rabies vaccine boosters are required. The absolute protection period after a rabies vaccine booster is usually 3 months, and in most people it is 6 months. Rabies can only be prevented but not treated, and once prevention fails, the fatality rate is 100%, so it is recommended that the protection period of the booster shots be limited to about six months. How long a rabies booster shot lasts is determined on a case-by-case basis. It is recommended that if you are re-exposed after a rabies booster shot, you should seek medical attention in a timely manner, and your doctor will take the appropriate measures to deal with the situation and determine if you need to receive a rabies vaccine. In addition, it is important to get enough rest and avoid overexertion after a rabies vaccine booster.