After being bitten by a dog, it is not always necessary to give a person an injection, which is mainly to consider whether the dog will transmit rabies to people. If the bite is very light, this light means that there is no obvious visible wound, no broken skin, the place where the bite was not even red, and no pain is felt when wiped up with alcohol, the wound is then called primary exposure, and rabies will not be transmitted in this case. However, after being bitten by a dog, there will be small broken skin, and this situation belongs to secondary exposure, and the situation with bleeding belongs to tertiary exposure. Both secondary and tertiary exposures are likely to require rabies vaccination of the person. Another way to determine if a dog is carrying rabies virus is to determine if the dog is healthy and there is no complete guarantee that it does not carry rabies virus. So when available, dogs can be tested accordingly, and if the dog is proven not to carry rabies virus, there is no need to give a person a shot to prevent rabies. However, this is rarely the case in clinical practice, and is mostly judged indirectly by whether the dog has been regularly and regularly vaccinated against rabies.