Pneumococcal Vaccine Responses in Small Vulnerable Newborns (360G-Wellcome-342429_Z_25_Z)

Childhood mortality has shown an impressive 59% decline between 1990 to 2022; unfortunately, this reduction has not been equal. Low-incomes countries, and sub-Saharan Africa in particular, now account for the majority of global child deaths; currently the under-5 mortality rate per 1000 births in Africa is ten times that in Europe. In conjunction, the recent Lancet Small Vulnerable Newborn (SVN) Series highlighted key underlying risk factors for infant mortality, with 25% of live births carrying one or more vulnerabilities: low birthweight, small for gestational age, and/or prematurity. The gap in improving infant mortality between high- and low-income countries demonstrates the inequity faced by this population and the need to increase research around SVNs to inform new evidence-based interventions. Globally, SVNs have the most to gain from interventions to reduce infant mortality, such as vaccination, however they are drastically under-represented in vaccine efficacy trials and particularly in newer vaccines, there is little evidence of their efficacy in this population. Pneumococcal disease remains one of the most prevalent causes for pneumonia globally, despite the introduction of PCV13 across many countries. This project will characterise the response to PCV13 in SVNs, considering immunogenicity and B cell recruitment, durability of protection and mucosal immunity.