Vaccination is a crucial matter, as it is essential for better prevention of certain diseases. Generally, two shots of a vaccine should not be administered simultaneously. If symptoms such as fever, colds, or diarrhea are present, it is advisable to postpone the vaccination temporarily.

Can Two Shots of a Vaccine Be Administered Together?

Generally, two shots of a vaccine should not be administered simultaneously, and it is recommended to separate the inoculations. This is because mild reactions such as fever, diarrhea, redness, and swelling may occur after vaccination. If two shots are given together, especially when combining a Category I (free) vaccine with a Category II (paid) vaccine, it can be difficult to determine which vaccine caused the reaction.

How to Administer Different Vaccines at the Same Time?

The National Health and Family Planning Commission of China and the Chinese Center for Disease Control and Prevention recommend that, in principle, a maximum of two injectable vaccines and one oral vaccine can be administered at the same time, with injectable vaccines being given in different locations.

1. Administering Different Vaccines Simultaneously: Currently, all national immunization program vaccines can be administered simultaneously according to the immunization schedule or catch-up principles. Two or more injectable vaccines should be given in different locations. It is strictly prohibited to mix two or more vaccines into the same syringe for inoculation.

2. Vaccination Interval for Different Vaccines: For two or more attenuated live vaccines used in the national immunization program that are not administered simultaneously, the interval between inoculations should be at least 28 days. There is no restriction on the interval between inactivated vaccines and oral polio attenuated live vaccines used in the national immunization program if they are not administered simultaneously with other types of national immunization program vaccines (including attenuated and inactivated vaccines).

3. If there is a conflict between the administration times of Category I and Category II vaccines, priority should be given to ensuring the administration of Category I vaccines.