NIHR Global Health Research Group on Vaccines for vulnerable people in Africa (VAnguard): Concept and Launch event report.

Vaccination is an important public health intervention but not everyone benefits equally. Some vaccines give weaker protection in people from rural, tropical settings than in those from high income settings. Some new vaccines, under development, also elicit weaker responses in people living in low-income, rural settings. The biological reasons for this are not fully understood. Also, some people benefit less from vaccines for socioeconomic reasons, such as the social context of the communities they live in, including limited access to accurate information to aid vaccine choices. Social and biological factors can interact to make communities "vulnerable" in terms of vaccine impact. This needs to be addressed to promote health equity, but also to secure maximum global benefit from vaccines. VAnguard's goal is to understand how biological, social, and structural factors interact to impair vaccine impact in vulnerable African communities, and to develop integrated strategies to optimise vaccine benefits and drive health equity. First, we shall work with national stakeholders (such as Ministries of Health, and vaccine-related non-governmental organisations), review literature, and work on samples from previous studies, to identify Ugandan and Kenyan communities likely to have the most difficulty in getting the best out of vaccination programmes ("vulnerable communities"). Then, with stakeholders and communities, we shall co-design the VAnguard Community Study, and implement it to investigate in detail which biological and social factors most influence vaccine impact in vulnerable communities. Data and economic modellers will study the results to identify which factors could usefully be modified, and we shall work with the communities to explore ways in which this could be done. Hence, we shall co-develop strategies which national stakeholders may be able to implement straight away, or which can be tested in future studies.