A systematised review and evidence synthesis on the broader societal impact of vaccines against Salmonella.

Vaccines against Salmonella Typhi are available, while vaccines against invasive non-typhoidal Salmonella are in development. Investments in vaccine development and introduction need to be informed by a full value of vaccines assessment, including consideration of broader societal impacts of salmonellae disease. We reviewed literature on these broader impacts in low- and middle-income countries to inform a conceptual framework. We found 16 studies relevant to Salmonella, but only one study on non-typhoidal Salmonella. Despite variations in study design, methodology, and study quality, salmonellae infections were largely associated with negative broader societal impacts, including detriments in childhood physical development (very weak association), childhood educational development (strong to very strong association), household security (moderate association), public health spending (moderate association), and national income (moderate to strong association). Study quality was low for all impacts except childhood physical development. There were no studies measuring economic impact of antimicrobial resistance, changes in household behaviour or health inequalities.