Table 2.
Attributes of Participants Reporting High-Risk Exposure With Differing Characteristics of Contact
| Participant Attribute | Relationship to Contact | Exposure Setting | Duration of Exposure | Nature of Contact | |||||
|---|---|---|---|---|---|---|---|---|---|
| Nonhousehold Member | Household Member | Outdoor Exposure Only | Any Indoor Exposure | <3 Hours | >3 Hours | Nonphysical Contact Only | Any Physical Contact | ||
| n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | ||
| N = 559 | N = 444 | N = 91 | N = 880 | N = 252 | N = 728 | N = 363 | N = 594 | ||
| Age, years | |||||||||
| 0–6 | 12 (2.1) | 25 (5.6) | 1 (1.1) | 35 (4.0) | 3 (1.2) | 34 (4.7) | 2 (0.6) | 31 (5.2) | |
| 7–12 | 31 (5.5) | 30 (6.8) | 3 (3.3) | 53 (6.0) | 6 (2.4) | 53 (7.3) | 20 (5.5) | 36 (6.1) | |
| 13–17 | 31 (5.5) | 36 (8.1) | 8 (8.8) | 54 (6.1) | 6 (2.4) | 55 (7.6) | 18 (5.0) | 40 (6.7) | |
| 18–29 | 183 (32.7) | 115 (25.9) | 29 (31.9) | 258 (29.3) | 81 (32.1) | 208 (28.6) | 121 (33.3) | 163 (27.4) | |
| 30–49 | 195 (34.9) | 156 (35.1) | 33 (36.3) | 310 (35.2) | 95 (37.7) | 252 (34.6) | 131 (36.1) | 209 (35.2) | |
| 50–64 | 78 (14.0) | 57 (12.8) | 10 (11.0) | 123 (14.0) | 42 (16.7) | 91 (12.5) | 49 (13.5) | 83 (14.0) | |
| ≥65 | 29 (5.2) | 25 (5.6) | 7 (7.7) | 47 (5.3) | 19 (7.5) | 35 (4.8) | 22 (6.1) | 32 (5.4) | |
| Sex | |||||||||
| Male | 256 (45.8) | 204 (45.9) | 46 (50.5) | 395 (44.9) | 117 (46.4) | 334 (45.9) | 177 (48.8) | 259 (43.6) | |
| Female | 303 (54.2) | 240 (54.1) | 45 (49.5) | 485 (55.1) | 135 (53.6) | 394 (54.1) | 186 (51.2) | 335 (56.4) | |
| Household income | |||||||||
| Less than $50 000 | 146 (26.1) | 98 (22.1) | 21 (23.1) | 219 (24.9) | 62 (24.6) | 178 (24.5) | 93 (25.6) | 147 (24.7) | |
| $50 000–$100 000 | 121 (21.6) | 111 (25.0) | 17 (18.7) | 205 (23.3) | 54 (21.4) | 170 (23.4) | 76 (20.9) | 141 (23.7) | |
| $100 000–$150 000 | 84 (15.0) | 43 (9.7) | 11 (12.1) | 114 (13.0) | 36 (14.3) | 91 (12.5) | 37 (10.2) | 84 (14.1) | |
| More than $150 000 | 66 (11.8) | 61 (13.7) | 7 (7.7) | 119 (13.5) | 25 (9.9) | 102 (14.0) | 43 (11.8) | 81 (13.6) | |
| Refuse | 91 (16.3) | 79 (17.8) | 19 (20.9) | 141 (16.0) | 44 (17.5) | 120 (16.5) | 65 (17.9) | 92 (15.5) | |
| Not sure | 51 (9.1) | 52 (11.7) | 16 (17.6) | 82 (9.3) | 31 (12.3) | 67 (9.2) | 49 (13.5) | 49 (8.2) | |
| Race/ethnicity | |||||||||
| Non-Hispanic White | 250 (44.7) | 190 (42.8) | 30 (33.0) | 396 (45.0) | 105 (41.7) | 325 (44.6) | 144 (39.7) | 274 (46.1) | |
| Non-Hispanic Black | 27 (4.8) | 18 (4.1) | 2 (2.2) | 43 (4.9) | 9 (3.6) | 35 (4.8) | 15 (4.1) | 29 (4.9) | |
| Hispanic (any race) | 125 (22.4) | 127 (28.6) | 36 (39.6) | 209 (23.8) | 65 (25.8) | 182 (25.0) | 104 (28.7) | 141 (23.7) | |
| Asian | 46 (8.2) | 37 (8.3) | 3 (3.3) | 75 (8.5) | 20 (7.9) | 60 (8.2) | 38 (10.5) | 40 (6.7) | |
| Native American | 10 (1.8) | 7 (1.6) | 0 (0.0) | 17 (1.9) | 4 (1.6) | 13 (1.8) | 5 (1.4) | 12 (2.0) | |
| Native Hawaiian | 4 (0.7) | 1 (0.2) | 1 (1.1) | 4 (0.5) | 2 (0.8) | 3 (0.4) | 4 (1.1) | 1 (0.2) | |
| More than 1 race | 70 (12.5) | 51 (11.5) | 12 (13.2) | 107 (12.2) | 38 (15.1) | 83 (11.4) | 42 (11.6) | 74 (12.5) | |
| Refuse | 27 (4.8) | 13 (2.9) | 7 (7.7) | 29 (3.3) | 9 (3.6) | 27 (3.7) | 11 (3.0) | 23 (3.9) | |
| Region | |||||||||
| Predominantly urban regions | |||||||||
| San Francisco Bay area | 52 (9.3) | 55 (12.4) | 9 (9.9) | 96 (10.9) | 17 (6.7) | 89 (12.2) | 36 (9.9) | 66 (11.1) | |
| Greater Los Angeles area | 47 (8.4) | 49 (11.0) | 13 (14.3) | 82 (9.3) | 19 (7.5) | 78 (10.7) | 33 (9.1) | 64 (10.8) | |
| Greater Sacramento area | 64 (11.4) | 64 (14.4) | 15 (16.5) | 106 (12.0) | 36 (14.3) | 84 (11.5) | 52 (14.3) | 69 (11.6) | |
| San Diego and southern border | 59 (10.6) | 37 (8.3) | 8 (8.8) | 85 (9.7) | 24 (9.5) | 70 (9.6) | 35 (9.6) | 56 (9.4) | |
| Predominantly rural regions | |||||||||
| Central Coast | 74 (13.2) | 53 (11.9) | 11 (12.1) | 115 (13.1) | 28 (11.1) | 97 (13.3) | 49 (13.5) | 74 (12.5) | |
| Northern Sacramento Valley | 58 (10.4) | 48 (10.8) | 10 (11.0) | 93 (10.6) | 33 (13.1) | 70 (9.6) | 29 (8.0) | 73 (12.3) | |
| San Joaquin Valley | 65 (11.6) | 46 (10.4) | 6 (6.6) | 102 (11.6) | 34 (13.5) | 76 (10.4) | 44 (12.1) | 61 (10.3) | |
| Northwestern California | 72 (12.9) | 44 (9.9) | 12 (13.2) | 99 (11.2) | 38 (15.1) | 74 (10.2) | 47 (12.9) | 62 (10.4) | |
| Sierras region | 68 (12.2) | 48 (10.8) | 7 (7.7) | 102 (11.6) | 23 (9.1) | 90 (12.4) | 38 (10.5) | 69 (11.6) | |
| County reopening tier | |||||||||
| Purple (most restrictive) | 102 (18.2) | 98 (22.1) | 23 (25.3) | 174 (19.8) | 59 (23.4) | 140 (19.2) | 84 (23.1) | 112 (18.9) | |
| Red | 113 (20.2) | 92 (20.7) | 19 (20.9) | 183 (20.8) | 56 (22.2) | 145 (19.9) | 80 (22.0) | 119 (20.0) | |
| Orange | 97 (17.4) | 103 (23.2) | 13 (14.3) | 183 (20.8) | 43 (17.1) | 154 (21.2) | 72 (19.8) | 122 (20.5) | |
| Yellow (least restrictive) | 13 (2.3) | 10 (2.3) | 1 (1.1) | 22 (2.5) | 6 (2.4) | 17 (2.3) | 9 (2.5) | 14 (2.4) | |
| After 15 June | 234 (41.9) | 141 (31.8) | 35 (38.5) | 318 (36.1) | 88 (34.9) | 272 (37.4) | 118 (32.5) | 227 (38.2) | |
| Vaccination | |||||||||
| Unvaccinated | 326 (63.3) | 321 (74.5) | 53 (61.6) | 578 (69.6) | 136 (58.1) | 496 (71.8) | 230 (68.2) | 393 (69.3) | |
| Partially vaccinateda | 45 (8.7) | 38 (8.8) | 9 (10.5) | 71 (8.6) | 37 (15.8) | 45 (6.5) | 37 (11.0) | 43 (7.6) | |
| Fully vaccinated | 144 (28.0) | 72 (16.7) | 24 (27.9) | 181 (21.8) | 61 (26.1) | 150 (21.7) | 70 (20.8) | 131 (23.1) | |
| Symptoms experienced | |||||||||
| No symptoms | 246 (44.0) | 160 (36.0) | 50 (54.9) | 336 (38.2) | 128 (50.8) | 263 (36.1) | 166 (45.7) | 214 (36.0) | |
| Symptoms | 313 (56.0) | 284 (64.0) | 41 (45.1) | 544 (61.8) | 124 (49.2) | 465 (63.9) | 197 (54.3) | 380 (64.0) | |
| Level of anxiety about coronavirus disease 2019 | |||||||||
| Very anxious | 89 (15.9) | 66 (14.9) | 17 (18.7) | 135 (15.3) | 40 (15.9) | 114 (15.7) | 57 (15.7) | 93 (15.7) | |
| Not very anxious | 470 (84.1) | 378 (85.1) | 74 (81.3) | 745 (84.7) | 212 (84.1) | 614 (84.3) | 306 (84.3) | 501 (84.3) | |
Percentages presented in the table should be interpreted to represent the proportion of cases or controls with each characteristic and not their prevalence within the general population.
An individual was considered partially vaccinated if their severe acute respiratory syndrome coronavirus 2 test date with <14 days before their second dose of an mRNA vaccine product (Pfizer/BioNTech BNT-162b2 or Moderna mRNA-1273) or <14 days after their first dose of a single-dose product (Jansen Pharmaceutical Companies JNJ-78436735).