Redness, swelling and hard lumps after vaccination can be warmed up with a towel, and in serious cases, it is recommended to go to the hospital for examination. After vaccination, redness, swelling and hard lumps at the inoculation site may be a normal post-vaccination adverse reaction, or it may be due to improper inoculation techniques, infection at the inoculation site and other reasons. Redness, swelling and hardness caused by normal post-inoculation adverse reaction or improper inoculation technique can be treated with localized hot compresses, which can help to promote local blood circulation and relieve the symptoms. Usually the adverse reaction can subside within a few days. If after three days, the redness and swelling still does not subside or significantly aggravated by pus or fluctuating sensation, may be the occurrence of infection, you need to go to the hospital in a timely manner, and under the guidance of the doctor to carry out anti-infection treatment. Care should be taken not to rub the vaccinated area, as rubbing may worsen the symptoms.