Co-administration of COVID-19 and influenza vaccines.

It will also be critical to continue assessing co-administration of other vaccines in the future, since COVID-19 vaccine boosters are likely to be part of routine immunization in the future, at least in selected vulnerable population. It will be particularly critical to assess the safety of simultaneous immunization with vaccines that are equally reactogenic than the current COVID-19 vaccines, such as adjuvanted vaccines. Eventually, the development of combination vaccines in adults, following the model of pediatric vaccines, is also urgently needed to optimize vaccine coverage and alleviate any remaining concerns on vaccine co-administration.