Table 6.

Incidence rates of breakthrough infections across entire matched cohorts (all states included), split by month.

Month	mRNA-1273 Incidence Rate Events/Person-Days [Per 1000 Person-Days] (# Individuals Contributing)	BNT162b2 Incidence Rate Events/Person-Days [Per 1000 Person-Days] (# Individuals Contributing)	IRR mRNA-1273 / BNT162b2
February	0/30026.0 [0] (n = 3770)	0/31074.0 [0] (n = 3351)	N/A
March	6/268901.0 [0.022] (n = 15373)	8/281110.0 [0.028] (n = 14188)	0.78 (0.22, 2.6)
April	12/612527.0 [0.02] (n = 26911)	24/647037.0 [0.037] (n = 28001)	0.53 (0.24, 1.1)
May	14/921359.0 [0.015] (n = 32862)	18/965133.0 [0.019] (n = 34577)	0.81 (0.38, 1.7)
June	15/997221.0 [0.015] (n = 35193)	27/1040827.0 [0.026] (n = 36789)	0.58 (0.29, 1.1)
July	58/1065321.0 [0.054] (n = 35710)	138/1112136.0 [0.12] (n = 37337)	0.44 (0.32, 0.6)