Table 2.
Characteristics of participants with prior SARS-CoV-2 infection category
| Prior SARS-CoV-2 infection status | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
| |||||||||||
| N | No evidence of prior infection | Confirmed†,‡ or possible§ prior infection | Serologic† | Documented‡ | Self-reported§ | ||||||
|
| |||||||||||
| N | No. | % | No. | % | No. | %¶ | No. | %¶ | No. | %¶ | |
|
| |||||||||||
| 1577 | 731 | 46 | 846 | 54 | 790 | 50 | 171 | 11 | 212 | 13 | |
|
| |||||||||||
| Age (years) | |||||||||||
| Mean (SD) | 42.5 (15.3) | 43.1 (15.9) | 43.3 (16.0) | 43.2 (14.6) | 39.3 (14.7) | ||||||
| 18–49 | 1055 | 506 | 48 | 549 | 52 | 507 | 48 | 111 | 11 | 157 | 15 |
| 50–64 | 348 | 150 | 43 | 198 | 57 | 189 | 54 | 45 | 13 | 40 | 11 |
| ≥65 | 174 | 75 | 43 | 99 | 57 | 94 | 54 | 15 | 9 | 15 | 9 |
| Sex | |||||||||||
| Female | 1003 | 458 | 46 | 545 | 54 | 509 | 51 | 125 | 12 | 148 | 15 |
| Male | 574 | 273 | 48 | 301 | 52 | 281 | 49 | 46 | 8 | 64 | 11 |
| Race and Ethnicity †† | |||||||||||
| White | 1067 | 482 | 45 | 585 | 55 | 540 | 51 | 115 | 11 | 149 | 14 |
| Black | 83 | 39 | 47 | 44 | 53 | 44 | 53 | 4 | 5 | 11 | 13 |
| Hispanic | 254 | 112 | 44 | 142 | 56 | 135 | 53 | 39 | 15 | 37 | 15 |
| Asian | 142 | 81 | 57 | 61 | 43 | 57 | 40 | 9 | 6 | 11 | 8 |
| Other/Unknown | 31 | 17 | 55 | 14 | 45 | 14 | 45 | 4 | 13 | 4 | 13 |
| Highest level of education obtained ‡‡ | |||||||||||
| High School or less | 271 | 123 | 45 | 148 | 55 | 137 | 51 | 34 | 13 | 40 | 15 |
| College | 970 | 441 | 45 | 529 | 55 | 494 | 51 | 112 | 12 | 151 | 16 |
| Advanced Degree | 332 | 166 | 50 | 166 | 50 | 156 | 47 | 24 | 7 | 21 | 6 |
| Self-reported Chronic Medical Condition §§ | |||||||||||
| Yes | 442 | 213 | 48 | 229 | 52 | 212 | 48 | 45 | 10 | 53 | 12 |
| No | 1135 | 518 | 46 | 617 | 54 | 578 | 51 | 126 | 11 | 159 | 14 |
| High-Risk SARS-CoV-2 exposure ¶¶ | |||||||||||
| Yes | 643 | 281 | 44 | 362 | 56 | 340 | 53 | 76 | 12 | 103 | 16 |
| No | 934 | 450 | 48 | 484 | 52 | 450 | 48 | 95 | 10 | 109 | 12 |
| Number of COVID-19 vaccine doses ††† | |||||||||||
| Unvaccinated | 289 | 135 | 47 | 154 | 53 | 137 | 47 | 43 | 15 | 63 | 22 |
| 2-dose | 647 | 389 | 60 | 258 | 40 | 235 | 36 | 70 | 11 | 81 | 13 |
| 3-dose | 641 | 207 | 32 | 434 | 68 | 418 | 65 | 58 | 9 | 68 | 11 |
| SARS-CoV-2 test result at enrollment | |||||||||||
| Positive | 455 | 246 | 54 | 209 | 46 | 192 | 42 | 38 | 8 | 41 | 9 |
| Negative | 1122 | 485 | 43 | 637 | 57 | 598 | 53 | 133 | 12 | 171 | 15 |
Nucleocapsid protein (NP) seropositive by multiplex SARS-CoV-2 bead assay (FlexImmArray, Tetracore).
Laboratory confirmed SARS-CoV-2 infection documented in electronic health record (EHR) >90 days before onset of current illness.
Participant self-report of prior confirmed COVID-19 or positive SARS-CoV-2 test >90 days before onset of current illness
Denominator is the row total for the header row. Categories of prior SARS-CoV-2 infection status are not mutually exclusive and sum to more than 100%.
Race and Hispanic ethnicity as participant reported at enrollment. Participants could select more than one. ‘Other’ category includes Native Hawaiian or other Pacific Islander and American Indian or Alaska Native.
Unknown for four participants.
Conditions included heart disease, lung disease, diabetes, cancer, liver/kidney disease, immune suppression, or high blood pressure
High-risk SARS-CoV-2 exposures included healthcare work in close contact with patients, close contact in the 14 days before illness onset with either a person with laboratory-confirmed SARS-CoV-2 or a household member with laboratory-confirmed SARS-CoV-2 or symptoms consistent with COVID-19-like illness.
Number of COVID-19 vaccine doses reported in a participant’s electronic health record.