Fig. 1

a HCV cases aggregated at the census tract level in Massachusetts, 2002–2013. b HCV rates per 100,000 in Massachusetts census tracts, 2002–2013. c Density of HCV cases per square mile in Massachusetts, 2002–2013. d HCV clusters in Massachusetts based on reported HCV counts aggregated at the census tract level (n = 1464). Census tracts with elevated numbers of HCV cases (red) represent hotspots (p < 0.05); census tracts with low numbers of HCV cases (blue) represent coldspots (p < 0.05); census tracts with average numbers of HCV cases are represented in yellow. e HCV clusters in Massachusetts based on rates per 100,000 population at the census tract level. Census tracts with elevated HCV rates (red) represent hotspots (p < 0.05); census tracts with low HCV rates (blue) represent coldspots (p < 0.05); census tracts with average HCV rates are represented in yellow; f Space-time clusters of HCV in Massachusetts, 2002–2013