ATAGI targeted review 2025: Immunisation considerations for immunocompromised people in Australia

Vaccination plays a pivotal role in protecting people who are immunocompromised, and who may therefore be at increased risk of infectious diseases, including vaccine preventable diseases (VPDs). However, there are special challenges in clinical practice and the development of immunisation policies to accurately address the vaccination needs of this heterogeneous population. This review aims to highlight the immunisation needs and challenges of immunocompromised populations, and to summarise the rationale behind the immunisation recommendations for these populations in Australia. The chapter Vaccination for people who are immunocompromised, in the Australian Immunisation Handbook, was recently updated by the Australian Technical Advisory Group on Immunisation (ATAGI). The updated chapter introduces new categorisation and risk classification for various types of immunocompromise, alongside the principles of immunisation. When planning immunisation for immunocompromised people, it is crucial to consider their underlying diagnoses, exposure to immunosuppressive therapies, susceptibility to VPDs, and their immune response to vaccination. Strategies to improve protection for immunocompromised persons include booster doses or altered schedules of routine vaccines; additional vaccines to prevent specific VPDs; and complete revaccination following immune reconstitution. Several national and jurisdictional vaccination programs have been implemented for immunocompromised populations (alongside other priority populations); however, monitoring vaccine coverage in these groups is challenging, and strategies to improve coverage are needed. There are significant evidence gaps in vaccine research for immunocompromised people, particularly regarding the optimal timing and scheduling of vaccinations to ensure maximum efficacy and safety. Future research should prioritise the inclusion of immunocompromised people in clinical trials and should integrate evidence from post-licensure use through data linkage. Emerging vaccine technologies may enable the development of more immunogenic vaccines or may offer more effective vaccination strategies for better protection against VPDs in immunocompromised people.