Table 1.

Vaccine effectiveness (VE) by vaccination dose and month, January 2021 to December 2021.

	Dose 1		Dose 2		Dose 3		All vaccinated
Month	VE	95% CI	VE	95% CI	VE	95% CI	VE	95% CI
January 2021	23.7	15.9–30.7	97.3	96.4–98.0	–	–	28.9	21.6–35.5
February 2021	57.7	55.2–60.1	93.4	85.5–97.0	–	–	59.5	57.1–61.8
March 2021	75.3	73.1–77.3	95.2	88.9–97.9	–	–	76.3	74.2–78.3
April 2021	80.1	77.4–82.5	90.5	85.6–93.7	–	–	83.6	81.4–85.6
May 2021	77.3	71.9–81.7	92.7	90.1–94.7	–	–	87.9	85.8–89.8
June 2021	68.7	62.9–73.6	92.0	91.0–92.8	–	–	88.3	87.2–89.3
July 2021	68.4	64.9–71.6	91.1	90.7–91.5	–	–	90.0	89.5–90.4
August 2021	69.6	66.1–72.7	90.0	89.6–90.4	–	–	89.3	88.8–89.7
September 2021	66.0	61.5–69.9	85.6	85.0–86.2	–	–	85.1	84.4–85.7
October 2021	59.8	54.5–64.4	81.0	80.1–81.8	91.8	90.0–93.2	81.6	80.8–82.4
November 2021	61.5	56.2–66.2	78.7	77.7–79.7	94.7	94.1–95.2	86.1	85.4–86.7
December 2021	57.3	52.5–61.6	75.3	74.1–76.5	92.4	91.9–92.8	88.5	88.0–88.9

Dose 1 equals those who received only one dose, Dose 2 equals those who received only two doses, Dose 3 equals those who received three or more doses.