Table 2.

COVID-19 vaccine effectiveness against symptomatic SARS-CoV-2 infection, hospitalization, severe COVID-19, and death among IMSS pensioners, either of any vaccine or by vaccine type, overall and stratified by days since full-vaccination: ≤90 days, 91–140 days, and ≥141 days, April–November 2021.

	Symptomatic Infection			Hospitalization			Severe COVID-19			Death
	Positive tests, n	Negative tests, n	VE, % (95% CI)	Positive tests	Negative tests	VE, % (95% CI)	Positive tests	Negative tests	VE, % (95% CI)	Positive tests	Negative tests	VE, % (95% CI)
Unvaccinated
Unvaccinated	3265	2665	–	2469	2665	–	1855	2665	–	1846	2665	–
Anyvaccine
Overall	8947	14,349	56.3 [53.5, 59]	3818	14,349	75.3 [73.4, 77]	2383	14,349	79.7 [78, 81.3]	2359	14,349	79.8 [78.1, 81.4]
≤90 days	2585	4895	62.8 [59.5, 65.9]	977	4895	80.3 [78.2, 82.3]	592	4895	84.7 [82.7, 86.4]	586	4895	84.8 [82.8, 86.5]
91–140 days	3875	4318	53.9 [50.1, 57.5]	1677	4318	74 [71.4, 76.3]	1083	4318	78.9 [76.6, 81]	1075	4318	79 [76.7, 81.1]
≥141 days	2487	5136	53.8 [49.2, 58]	1164	5136	71.2 [67.8, 74.2]	708	5136	75.4 [72.1, 78.4]	698	5136	75.6 [72.3, 78.5]
BNT162b2 (Pfizer-BioNTech)
Overall	2208	5184	69.8 [67.3, 72]	878	5184	84.1 [82.5, 85.6]	491	5184	88.2 [86.7, 89.5]	483	5184	88.3 [86.9, 89.6]
≤90 days	433	1502	74.3 [70.5, 77.6]	155	1502	87.5 [84.9, 89.7]	90	1502	90.4 [87.8, 92.4]	90	1502	90.3 [87.7, 92.4]
91–140 days	982	1558	70.1 [66.6, 73.2]	376	1558	85.3 [83.1, 87.2]	216	1558	89.5 [87.6, 91.1]	215	1558	89.5 [87.6, 91.1]
≥141 days	793	2124	66.9 [62.7, 70.7]	347	2124	80.5 [77.4, 83.2]	185	2124	85.3 [82.3, 87.8]	178	2124	85.7 [82.8, 88.2]
AZD1222 (Oxford-AstraZeneca)
Overall	2383	3846	56.8 [53.2, 60.1]	996	3846	76.2 [73.8, 78.4]	630	3846	80.3 [77.9, 82.4]	623	3846	80.4 [78.1, 82.5]
≤90 days	1200	1774	61.2 [56.9, 65.1]	443	1774	81.1 [78.4, 83.5]	274	1774	85.3 [82.8, 87.5]	271	1774	85.4 [82.9, 87.6]
91–140 days	764	1140	57.8 [52.4, 62.6]	358	1140	73.7 [69.5, 77.3]	238	1140	77.1 [72.9, 80.7]	235	1140	77.3 [73.2, 80.9]
≥141 days	419	932	51.8 [43.5, 58.8]	195	932	70.5 [64.2, 75.8]	118	932	73.5 [66.5, 79.1]	117	932	73.6 [66.6, 79.2]
CoronaVac (Sinovac)
Overall	3103	3437	39.1 [34.1, 43.7]	1393	3437	63.8 [60.4, 67]	923	3437	68.4 [64.9, 71.5]	916	3437	68.5 [65.1, 71.6]
≤90 days	726	1087	47 [39.6, 53.5]	307	1087	69.8 [64.5, 74.2]	192	1087	75.4 [70.3, 79.7]	190	1087	75.6 [70.5, 79.8]
91–140 days	1496	1083	36.1 [28.7, 42.7]	658	1083	63.8 [58.9, 68.1]	443	1083	69.8 [65.2, 73.8]	439	1083	70 [65.3, 74]
≥141 days	881	1267	34.9 [26.2, 42.6]	428	1267	57.8 [51, 63.6]	288	1267	59.2 [51.6, 65.5]	287	1267	59.2 [51.6, 65.5]
Ad5-nCoV (CanSino)
Overall	774	727	30.5 [21.2, 38.6]	391	727	52.1 [44.5, 58.6]	263	727	59.2 [51.8, 65.6]	262	727	59.2 [51.8, 65.6]
≤90 days	103	172	29 [5.3, 46.7]	43	172	58.2 [39, 71.3]	24	172	69.4 [50.6, 81]	24	172	69.1 [50, 80.8]
91–140 days	411	207	14.3 [−3.5, 29.1]	207	207	42.9 [29.3, 54]	147	207	52.1 [39.3, 62.1]	147	207	51.9 [39, 62]
≥141 days	260	348	43.6 [32.1, 53.1]	141	348	58.8 [48.7, 66.9]	92	348	63.8 [53.2, 72]	91	348	64.1 [53.6, 72.3]
Gam-COVID-Vac Sputnik V (Gamaleya Research Institute)
Overall	479	1155	70 [64.8, 74.4]	160	1155	86.8 [83.7, 89.3]	76	1155	91.9 [89.4, 93.9]	75	1155	92 [89.5, 93.9]
≤90 days	123	360	68.5 [59.5, 75.5]	29	360	90.4 [85.5, 93.7]	12	360	94.8 [90.5, 97.2]	11	360	95.2 [91, 97.4]
91–140 days	222	330	66.2 [58.2, 72.7]	78	330	84.6 [79.5, 88.4]	39	330	90.5 [86.4, 93.4]	39	330	90.5 [86.3, 93.4]
≥141 days	134	465	75.5 [69.1, 80.6]	53	465	87.1 [82.2, 90.6]	25	465	91.8 [87.3, 94.7]	25	465	91.8 [87.3, 94.7]

Abbreviations: 95% CI, 95% confidence interval; VE, vaccine effectiveness.