Rural-like gut microbiota profiles are linked to high yellow fever antibody titers but rapid waning in a healthy Tanzanian population

Vaccine responses vary across populations and are influenced by numerous intrinsic and extrinsic factors. Increasing evidence indicates that the gut microbiota may play a role in modulating vaccine responses. However, human studies linking microbiota and vaccine immunogenicity in populations living in low- and middle-income countries, are sparse. The gut microbiota composition in 143 healthy rural and urban living Tanzanian adults who participated in a yellow fever vaccine (YF-17D) trial was studied. Significant differences in gut microbiota profiles between rural and urban individuals were found, with rural-associated microbiota profiles showing higher diversity and enrichment of among others Prevotella and Succinivibrio. These profiles were strongly associated with dietary intake of specific foods. Yellow fever neutralizing antibody titers post-vaccination were higher in rural- compared to urban living Tanzanians. Microbiota profiling revealed a group of urban living individuals with a rural-like microbiota who showed higher antibody titers and faster waning compared to urban counterparts with a more industrialized gut microbiota. These findings suggest that the gut microbiota composition is linked to vaccine immunogenicity, potentially outweighing the influence of living location.