Whether or not the rotavirus vaccine needs to be revaccinated after vomiting depends on the length of time between the onset of vomiting and the vaccination, and it is recommended to consult the doctor at the vaccination site. 1. Need to replenish the vaccine: If you vomit all of the vaccine immediately after oral administration, you generally need to replenish the vaccine. Because the oral mucosa has not absorbed the vaccine, the strength of the antibody is not enough, which may affect the effectiveness of the vaccine. 2. No need for vaccination: If only part of the vaccine is spit out, or if the vaccine stays in the mouth for a longer period of time, the vaccine may be partially absorbed and enough antibodies can be formed in the body, and then there is usually no need for vaccination. Rotavirus vaccine is an enterovirus vaccine, and the vaccine may be absorbed more, so it is recommended to consult with the doctor at the vaccination center for details, and then take the supplemental vaccination under the doctor’s guidance.