In principle, the following applies: live vaccines (attenuated, reproducible viruses or bacteria, e.g. measles, mumps, rubella and varicella combination vaccine or rotavirus vaccine) can be administered simultaneously, i.e. at the same time. If they are not administered simultaneously, a minimum interval of four weeks is usually required. When using inactivated vaccines, it is not necessary to observe minimum intervals - even with live vaccines. In the (rare) case of an acute vaccination reaction, the symptoms should have subsided before a new vaccination.
The recommended vaccination intervals should not be exceeded, as otherwise the effectiveness of the vaccine(s) cannot be guaranteed. Exceeding the intervals is not problematic for most vaccinations, but delays the build-up of immunity.