Socially Connected Neighborhoods and the Spread of Sexually Transmitted Infections

Sexually trans mit ted infec tions (STIs) in the United States have been increasing at record levels and exhibit unequal spatial patterning across urban populations and neighborhoods. Research on the effects of residential and nearby neighborhoods on STI proliferation has largely ignored the role of socially connected contexts, even though neighborhoods are routinely linked by individ u als’ movements across space for work and other social activities. We showcase how commuting and public transit networks contribute to the social spillover of STIs in Chicago. Examining data on all employee–employer location links recorded yearly by the Census Bureau for more than a decade, we assess network spillover effects of local community STI rates on interconnected communities. Spatial and network autoregressive models show that exposure to STIs in geographically proximate and socially proximate communities con trib utes to increases in local STI lev els, even net of socio eco nomic and demographic factors and prior STIs. These findings suggest that geographically proximate and socially connected communities influence one another’s infection rates through social spillover effects.