Gunshot wounds are contagious

Gun violence can ripple through social networks and communities just like an infectious germ, Harvard and Yale researchers reported Monday in JAMA Internal Medicine. This may not seem surprising, because earlier work has found that gun violence often clusters in certain areas and groups, particularly those steeped in gangs and drugs. But this study is the first to show that gun violence spreads directly from person to person after shootings—it’s not just about growing up in the same rough neighborhood or having the same risk factors.

The finding is good news, because, after decades of research, scientists are pretty good at predicting how infections cascade through populations. Applying disease-based theories and simulations to gun violence could help health workers get ahead of bullets and intervene before violence spreads. A more informed strategy could also cut down on intervention tactics that “rest largely on geographic or group-based policing efforts that tend to disproportionately affect disadvantaged minority communities,” the authors argue.