Table 1. Cohort characteristics and incidence of SARS-CoV-2 infection presented by month in a cohort of 9.1 million VA enrollees followed from February 2020 to March 2021.
| Cohort characteristics N (%) |
Number of SARS-CoV-2–positive persons (and incidence per 10,000 persons per month) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Time period and number of VA enrollees at risk* | Entire period: February 2020 to March 2021 N = 9,127,673 |
February to March 2020 N = 9,127,673 |
April 2020 N = 9,090,196 |
May 2020 N = 9,053,082 |
June 2020 N = 9,022,051 |
July 2020 N = 8,990,833 |
August 2020 N = 8,948,674 |
September 2020 N = 8,913,864 |
October 2020 N = 8,881,573 |
November 2020 N = 8,844,680 |
December 2020 N = 8,804,424 |
January 2021 N = 8,744,388 |
February 2021 N = 8,671,916 |
March 2021 N = 8,630,283 |
| All persons infected | 216,046 (100%) |
2,470 (2.7) |
7,346 (8.1) |
4,957 (5.5) |
7,634 (8.5) |
16,105 (17.9) |
9,189 (10.3) |
7,526 (8.4) |
13,523 (15.2) |
33,553 (37.9) |
47,357 (53.8) |
39,431 (45.1) |
17,698 (20.4) |
9,257 (10.7) |
| Sex | ||||||||||||||
| Female | 829,355 (9.1) |
218 (2.6) |
695 (8.4) |
453 (5.5) |
853 (10.3) |
1,946 (23.6) |
968 (11.8) |
716 (8.7) |
1,243 (15.2) |
3,315 (40.6) |
4,859 (59.7) |
3,942 (48.7) |
1,825 (22.7) |
1,003 (12.5) |
| Male | 8,298,318 (90.9) |
2,252 (2.7) |
6,651 (8.1) |
4,504 (5.5) |
6,781 (8.3) |
14,159 (17.3) |
8,221 (10.1) |
6,810 (8.4) |
12,280 (15.2) |
30,238 (37.7) |
42,498 (53.2) |
35,489 (44.7) |
15,873 (20.2) |
8,254 (10.5) |
| Age (years) | ||||||||||||||
| 18 to 24 | 81,085 (0.9) |
8 (1.0) |
26 (3.2) |
16 (2.0) |
88 (10.9) |
153 (18.9) |
66 (8.2) |
42 (5.2) |
69 (8.6) |
207 (25.7) |
303 (37.7) |
229 (28.6) |
86 (10.8) |
59 (7.4) |
| 25 to 34 | 828,607 (9.1) |
144 (1.7) |
388 (4.7) |
273 (3.3) |
919 (11.1) |
1,681 (20.3) |
737 (8.9) |
538 (6.5) |
993 (12.1) |
2,648 (32.2) |
3,633 (44.3) |
2,745 (33.6) |
1,220 (15.0) |
767 (9.4) |
| 35 to 44 | 1,069,496 (11.7) |
279 (2.6) |
614 (5.7) |
405 (3.8) |
1,005 (9.4) |
2,168 (20.3) |
1,018 (9.6) |
794 (7.5) |
1,488 (14.0) |
3,898 (36.7) |
5,409 (51.2) |
4,382 (41.7) |
1,879 (17.9) |
1,205 (11.5) |
| 45 to 54 | 1,175,283 (12.9) |
369 (3.1) |
860 (7.3) |
546 (4.7) |
1,174 (10.0) |
2,708 (23.1) |
1,364 (11.7) |
1,103 (9.5) |
1,952 (16.8) |
4,938 (42.5) |
6,790 (58.7) |
5,524 (48.1) |
2,455 (21.5) |
1,496 (13.1) |
| 55 to 64 | 1,517,143 (16.6) |
562 (3.7) |
1,514 (10.0) |
1,061 (7.0) |
1,420 (9.4) |
3,086 (20.5) |
1,810 (12.1) |
1,385 (9.3) |
2,506 (16.8) |
6,093 (40.9) |
8,846 (59.7) |
7,579 (51.5) |
3,478 (23.8) |
1,927 (13.2) |
| 65 to 74 | 2,434,839 (26.7) |
688 (2.8) |
2,111 (8.7) |
1,399 (5.8) |
1,808 (7.5) |
3,989 (16.6) |
2,554 (10.7) |
2,215 (9.3) |
3,938 (16.6) |
9,484 (40.1) |
13,197 (56.1) |
11,319 (48.5) |
5,167 (22.3) |
2,355 (10.2) |
| 75 to 84 | 1,257,097 (13.8) |
279 (2.2) |
1,022 (8.2) |
693 (5.6) |
795 (6.5) |
1,564 (12.8) |
1,123 (9.2) |
999 (8.3) |
1,797 (15.0) |
4,389 (36.8) |
6,368 (53.7) |
5,380 (45.7) |
2,384 (20.5) |
1,050 (9.1) |
| ≥85 | 764,123 (8.4) |
141 (1.8) |
811 (10.8) |
564 (7.7) |
425 (5.9) |
756 (10.6) |
517 (7.3) |
450 (6.5) |
780 (11.4) |
1,896 (28.0) |
2,811 (41.9) |
2,273 (34.2) |
1,029 (15.9) |
398 (6.2) |
| Race | ||||||||||||||
| White | 5,886,250 (64.5) |
956 (1.6) |
3,774 (6.4) |
2,739 (4.7) |
4,414 (7.6) |
9,315 (16.1) |
5,690 (9.9) |
5,141 (9.0) |
9,898 (17.3) |
24,753 (43.5) |
33,126 (58.5) |
26,626 (47.4) |
11,932 (21.4) |
6,425 (11.6) |
| Black | 1,337,163 (14.6) |
1,293 (9.7) |
2,919 (21.9) |
1,729 (13.0) |
2,319 (17.6) |
4,922 (37.4) |
2,544 (19.4) |
1,602 (12.3) |
2,267 (17.4) |
5,337 (41.2) |
8,959 (69.5) |
8,488 (66.4) |
3,909 (30.8) |
1,914 (15.2) |
| Asian | 114,794 (1.3) |
27 (2.4) |
55 (4.8) |
37 (3.2) |
75 (6.6) |
168 (14.7) |
81 (7.1) |
70 (6.2) |
95 (8.4) |
278 (24.6) |
550 (48.8) |
442 (39.4) |
191 (17.1) |
82 (7.4) |
| AI/AN | 79,738 (0.9) |
14 (1.8) |
54 (6.8) |
48 (6.1) |
92 (11.6) |
155 (19.7) |
79 (10.1) |
76 (9.7) |
147 (18.9) |
340 (43.9) |
439 (56.9) |
349 (45.6) |
162 (21.3) |
60 (7.9) |
| PI/NH | 75,186 (0.8) |
13 (1.7) |
57 (7.6) |
44 (5.9) |
77 (10.3) |
157 (21.1) |
101 (13.7) |
73 (9.9) |
115 (15.7) |
301 (41.1) |
440 (60.4) |
393 (54.3) |
177 (24.7) |
68 (9.5) |
| Missing/unknown/refused | 1,634,542 (17.9) |
167 (1.0) |
487 (3.0) |
360 (2.2) |
657 (4.1) |
1,388 (8.6) |
694 (4.3) |
564 (3.5) |
1,001 (6.3) |
2,544 (16.0) |
3,843 (24.2) |
3,133 (19.8) |
1,327 (8.4) |
708 (4.5) |
| Ethnicity | ||||||||||||||
| Non-Hispanic | 7,201,109 (78.9) |
2,119 (2.9) |
6,441 (9.0) |
4,365 (6.1) |
6,101 (8.6) |
12,936 (18.3) |
7,825 (11.1) |
6,615 (9.4) |
11,868 (17.0) |
29,477 (42.3) |
40,749 (58.8) |
33,980 (49.4) |
15,482 (22.7) |
8,014 (11.8) |
| Hispanic | 571,236 (6.3) |
272 (4.8) |
649 (11.4) |
426 (7.5) |
1,235 (21.8) |
2,583 (45.7) |
1,037 (18.5) |
645 (11.5) |
1,159 (20.8) |
2,819 (50.7) |
4,648 (84.1) |
3,791 (69.2) |
1,487 (27.4) |
861 (15.9) |
| Missing/unknown/refused | 1,355,328 (14.8) |
79 (0.6) |
256 (1.9) |
166 (1.2) |
298 (2.2) |
586 (4.4) |
327 (2.4) |
266 (2.0) |
496 (3.7) |
1,257 (9.5) |
1,960 (14.8) |
1,660 (12.6) |
729 (5.6) |
382 (2.9) |
| US Federal Region † | ||||||||||||||
| 1 | 400,339 (4.4) |
95 (2.4) |
852 (21.4) |
398 (10.1) |
196 (5.0) |
143 (3.6) |
102 (2.6) |
99 (2.5) |
219 (5.6) |
946 (24.5) |
1,674 (43.4) |
1,520 (39.7) |
760 (20.0) |
419 (11.1) |
| 2 | 665,463 (7.3) |
615 (9.2) |
1,717 (26.0) |
590 (9.0) |
267 (4.1) |
340 (5.2) |
217 (3.4) |
209 (3.2) |
380 (5.9) |
1,248 (19.5) |
2,183 (34.2) |
2,114 (33.3) |
1,079 (17.1) |
759 (12.1) |
| 3 | 958,643 (10.5) |
185 (1.9) |
838 (8.8) |
657 (6.9) |
459 (4.8) |
773 (8.2) |
581 (6.2) |
474 (5.1) |
830 (8.9) |
2,528 (27.1) |
4,474 (48.2) |
3,725 (40.4) |
1,815 (19.8) |
1,048 (11.5) |
| 4 | 2,290,207 (25.1) |
363 (1.6) |
1,085 (4.8) |
1,006 (4.4) |
2,474 (10.9) |
5,993 (26.5) |
3,416 (15.2) |
2,328 (10.4) |
3,045 (13.7) |
5,555 (25.0) |
11,123 (50.3) |
11,489 (52.3) |
5,354 (24.6) |
2,470 (11.4) |
| 5 | 1,325,949 (14.5) |
413 (3.1) |
1,230 (9.3) |
955 (7.3) |
605 (4.6) |
1,217 (9.3) |
1,007 (7.8) |
1,095 (8.5) |
3,058 (23.7) |
8,438 (65.8) |
7,528 (59.2) |
4,576 (36.3) |
2,187 (17.5) |
1,436 (11.5) |
| 6 | 1,194,444 (13.1) |
459 (3.8) |
658 (5.5) |
486 (4.1) |
1,744 (14.7) |
4,019 (34.1) |
1,687 (14.4) |
1,206 (10.3) |
2,161 (18.6) |
4,403 (38.0) |
6,419 (55.7) |
6,182 (54.0) |
2,338 (20.6) |
1,104 (9.8) |
| 7 | 458,363 (5.0) |
58 (1.3) |
238 (5.2) |
250 (5.5) |
221 (4.9) |
600 (13.3) |
681 (15.2) |
853 (19.1) |
1,432 (32.2) |
3,652 (82.6) |
3,057 (69.8) |
2,007 (46.2) |
935 (21.7) |
465 (10.9) |
| 8 | 374,484 (4.1) |
74 (2.0) |
208 (5.6) |
179 (4.8) |
147 (4.0) |
277 (7.5) |
241 (6.5) |
414 (11.3) |
1,100 (30.1) |
2,568 (70.6) |
1,908 (52.8) |
992 (27.7) |
515 (14.4) |
369 (10.4) |
| 9 | 1,041,079 (11.4) |
164 (1.6) |
387 (3.7) |
344 (3.3) |
1,376 (13.3) |
2,356 (22.9) |
967 (9.5) |
627 (6.2) |
860 (8.5) |
3,112 (30.7) |
7,725 (76.6) |
6,059 (60.6) |
2,253 (22.8) |
875 (8.9) |
| 10 | 418,702 (4.6) |
44 (1.1) |
133 (3.2) |
92 (2.2) |
145 (3.5) |
387 (9.3) |
290 (7.0) |
221 (5.4) |
438 (10.7) |
1,103 (27.0) |
1,266 (31.1) |
767 (18.9) |
462 (11.4) |
312 (7.8) |
| Urban versus rural | ||||||||||||||
| Rural | 4,469,258 (49.0) |
579 (1.3) |
1,870 (4.2) |
1,623 (3.7) |
2,955 (6.7) |
6,872 (15.6) |
4,680 (10.7) |
4,147 (9.5) |
7,468 (17.2) |
17,506 (40.4) |
23,772 (55.1) |
19,440 (45.4) |
8,734 (20.6) |
4,513 (10.7) |
| Urban | 4,658,415 (51.0) |
1,891 (4.1) |
5,476 (11.8) |
3,334 (7.2) |
4,679 (10.2) |
9,233 (20.1) |
4,509 (9.9) |
3,379 (7.4) |
6,055 (13.4) |
16,047 (35.6) |
23,585 (52.5) |
19,991 (44.8) |
8,964 (20.3) |
4,744 (10.8) |
| BMI (kg/m2) | ||||||||||||||
| <18.5 (underweight) | 64,634 (0.7) |
38 (5.9) |
148 (23.5) |
101 (16.4) |
95 (15.7) |
115 (19.3) |
98 (16.7) |
74 (12.8) |
105 (18.4) |
223 (39.6) |
374 (66.9) |
367 (66.4) |
159 (29.4) |
89 (16.6) |
| 18.5 to <25 (normal weight) | 1,841,422 (20.2) |
413 (2.2) |
1,448 (7.9) |
1,030 (5.7) |
1,218 (6.7) |
2,414 (13.4) |
1,362 (7.6) |
1,171 (6.6) |
1,864 (10.5) |
4,658 (26.5) |
6,929 (39.5) |
5,908 (33.9) |
2,703 (15.7) |
1,345 (7.8) |
| 25 to <30 (overweight) | 3,314,997 (36.3) |
794 (2.4) |
2,348 (7.1) |
1,602 (4.9) |
2,509 (7.7) |
5,183 (15.9) |
2,920 (9.0) |
2,460 (7.6) |
4,410 (13.6) |
10,898 (33.9) |
15,526 (48.4) |
12,829 (40.3) |
5,759 (18.2) |
2,928 (9.3) |
| 30 to <35 (obese I) | 2,433,428 (26.7) |
677 (2.8) |
1,901 (7.8) |
1,260 (5.2) |
2,181 (9.0) |
4,684 (19.5) |
2,679 (11.2) |
2,163 (9.1) |
3,969 (16.7) |
9,903 (41.7) |
13,689 (57.9) |
11,498 (49.0) |
5,096 (21.9) |
2,744 (11.8) |
| 35 to <40 (obese II) | 1,026,570 (11.2) |
355 (3.5) |
946 (9.2) |
633 (6.2) |
1,039 (10.2) |
2,358 (23.2) |
1,398 (13.8) |
1,031 (10.2) |
2,007 (20.0) |
4,995 (49.9) |
6,941 (69.7) |
5,696 (57.6) |
2,540 (25.9) |
1,371 (14.1) |
| ≥40 (obese III) | 446,622 (4.9) |
193 (4.3) |
555 (12.5) |
331 (7.5) |
592 (13.4) |
1,351 (30.6) |
732 (16.7) |
627 (14.3) |
1,168 (26.8) |
2,876 (66.3) |
3,898 (90.6) |
3,133 (73.5) |
1,441 (34.2) |
780 (18.6) |
| CCI | ||||||||||||||
| 0 to 1 | 6,063,266 (66.4) |
955 (1.6) |
2,620 (4.3) |
1,805 (3.0) |
3,799 (6.3) |
7,918 (13.2) |
4,197 (7.0) |
3,313 (5.5) |
6,130 (10.3) |
15,701 (26.4) |
21,571 (36.3) |
17,532 (29.7) |
8,062 (13.7) |
4,708 (8.0) |
| 2 to 3 | 1,520,767 (16.7) |
552 (3.6) |
1,649 (10.9) |
1,154 (7.7) |
1,575 (10.5) |
3,703 (24.8) |
2,093 (14.1) |
1,813 (12.3) |
3,253 (22.2) |
7,929 (54.3) |
11,334 (78.1) |
9,722 (67.7) |
4,332 (30.5) |
2,198 (15.6) |
| 4 to 5 | 768,966 (8.4) |
346 (4.5) |
1,153 (15.1) |
807 (10.7) |
985 (13.1) |
1,990 (26.6) |
1,301 (17.5) |
1,073 (14.6) |
1,815 (24.8) |
4,613 (63.4) |
6,557 (90.9) |
5,671 (79.5) |
2,427 (34.6) |
1,110 (15.9) |
| ≥6 | 774,674 (8.5) |
617 (8.0) |
1,924 (25.2) |
1,191 (15.8) |
1,275 (17.1) |
2,494 (33.8) |
1,598 (21.9) |
1,327 (18.4) |
2,325 (32.7) |
5,310 (75.5) |
7,895 (113.4) |
6,506 (94.9) |
2,877 (42.9) |
1,241 (18.7) |
* VA enrollees at risk are those who are still alive and not yet infected at the beginning of each time period.
† Categorized according to the 10 US Federal Regions drawn up by the Office of Management and Budget: 1 (CT, MA, ME, NH, RI, and VT), 2 (NJ, NY, PR, and Virgin Island), 3 (DC, DE, MD, PA, VA, and WV), 4 (AL, FL, GA, KY, MS, NC, SC, and TN), 5 (IL, IN, MI, MN, OH, and WI), 6 (AR, LA, NM, OK, and TX), 7 (IA, KS, MO, and NE), 8 (CO, MT, ND, SD, UT, and WY), 9 (AZ, CA, GU, HI, and NV), and 10 (AK, ID, OR, and WA).
AI/AN, American Indian/Alaska Native; CCI, Charlson comorbidity index; PI/NH, Pacific Islander/Native Hawaiian; SARS-CoV-2, Severe Acute Respiratory Syndrome Coronavirus 2; VA, Veterans Affairs.