The rabies virus is mainly caused by infection from dog bites or scratches. Although the probability of infection is relatively low, once infected, the mortality rate is 100%. Rabies vaccination is the only effective method of prevention. Can rabies prevention be achieved if the rabies vaccination is administered more than 72 hours after a dog bite or scratch? Rabies vaccine is recommended for all dog bites or scratches. Even if it has been more than 72 hours, the full vaccination may still be effective, so active vaccination is still required, and for those vaccinated more than 48 hours after exposure, it is recommended that the first dose be doubled. After being bitten or scratched by a dog, the first thing you can do is to treat the wound yourself in a standardized manner and wash it thoroughly with 20% soapy water. First, it is important to be quick and to rinse off the rabies virus that is staining the wound as fast as possible. This is because over time, the virus will gradually enter human tissue and gradually invade the central nervous system along the nerves. Second, be thorough. If the wound is small and deep, it is recommended to try to expand the wound area when rinsing so that the inside is fully exposed and try to get rid of the dog’s saliva. Third, the water flow should be rapid and large when rinsing to flush out the potential virus as much as possible. If conditions allow, it is recommended to use rabies professional cleaning equipment and special cleaning agents to rinse the inside of the wound. Fourth, saline rinsing the wound again after rinsing can avoid soap solution or other cleaning agent residue. If the wound is still bleeding there is no need to take measures to stop the bleeding, as this will help to take away the virus. After the wound is thoroughly rinsed, the inside of the wound is disinfected with dilute iodophor or other skin mucosal agent with virus inactivating effect. It is possible to prevent rabies attacks by injecting rabies vaccine according to the process before the attack. In principle, the earlier the rabies vaccination is given, the better, and the later the vaccination is given, the higher the failure rate of prevention. Some people believe that rabies vaccination cannot be given more than 72 hours later. In fact, this is not absolute, and it is currently believed that rabies vaccination must still be given even if it is more than 72 hours later, and rabies immunoglobulin or anti-rabies serum must be injected at the same time, and if only the vaccine is not injected with rabies immunoglobulin or anti-rabies serum after exposure, rabies immunoglobulin or anti-rabies serum can still be injected within 7 days of vaccination. If you have been vaccinated for more than 7 days, you are considered to have developed antibodies and there is no need to inject rabies immunoglobulin or anti-rabies serum. It is possible to prevent rabies with active treatment.