Gun violence is a huge public health problem in the US that disproportionately affects urban areas.  It claims the lives of an estimated 34,000 individuals each year through homicide, suicide, and accidental shootings.  Although the homicide rate in the US decreased from an estimated 5.5 per 100,000 in 2000, to 4.7 per 100,000 in 2012, this decline may mask potentially fatal gun injuries that do not result in death. Trends in gun violence over the past 30 years showed a large rise in the early 1990s nationally, followed by a decline and eventual steadying off through the 2000s. But such trends vary depending on the location. Chicago had its worst year in 2016 with nearly 2 murders per day, whereas New York City saw a dramatic decline.

National figures can obscure the fact that gun violence is not randomly distributed among the general population. Instead, it appears to be clustered in impoverished minority communities. Homicide was the sixth leading cause of death accounting for 2.8% of all deaths among Blacks, and accounted for 1.7% of Hispanic deaths, compared to 0.4% in predominantly white urban neighborhoods. Gun violence is also heavily concentrated within small social networks of young men suggesting a clustering effect just like an infectious diseases wherein just 20% of the population contributes 80% of the onward transmission of the disease. Beyond particular populations, gun violence clusters in particular locations as small as street corners. Such observations led investigators to study spatial and temporal patterns of gun violence in Syracuse, a large urban setting of estimated population 732,000 persons and median income $31,000, with one-third below the federal poverty line and a high concentration of poverty. Their findings, published in PloS One revealed statistically significant spatial temporal clusters of gun violence especially in census blocks with more rental units, increased vacant housing. The warmer months of May through October were associated with a significant increase in the risk of gun violence.  Their results point to the importance of urban planning that can ignore the segregation or concentration of poverty in neighborhoods already at high risk, thereby disrupt community cohesion. Community violence is associated with a multitude of negative effects for those residing in the community, not just the victims or witnesses of gun violence. It is associated with poor birth outcomes, poor cognitive performance and development in the children who reside in the affected neighborhoods. 

Neighborhoods with definable spatial and temporal trends of gun violence, especially those concentrated in poor urban areas, need to harness multifaceted interventions in order to respond to gun violence, and temper this epidemic problem.