Table 1.
Participant Characteristics (N = 152)
| Characteristic | No. (%)a |
|---|---|
| Age, mean (SD), y | 29.92 (10.71) |
| Women | 63 (41) |
| Race/ethnicityb | |
| White | 109 (72) |
| Black | 34 (22) |
| Other | 9 (6) |
| Education | |
| High school or less | 37 (24) |
| <2 y college, no degree | 43 (28) |
| 2 y college + associate’s degree | 31 (20) |
| Bachelor’s degree or higher | 41 (27) |
| Body mass index, mean (SD)c | 26.44 (5.68) |
| Days from blood draw to viral challenge, median (IQR) | 4 (3–50) |
| Prechallenge viral-specific antibody titer < 4 | 123 (81) |
| Season of exposure | |
| Winter | 39 (26) |
| Spring | 50 (33) |
| Summer | 63 (41) |
| Lymphocyte-relative T:S ratio, mean (SD), raw data | |
| PBMC (n = 128) | 0.81 (0.22) |
| CD4 (n = 146) | 0.53 (0.24) |
| CD8CD28+ (n = 132) | 0.55 (0.20) |
| CD8CD28− (n = 144) | 0.58 (0.27) |
Abbreviations: IQR, interquartile range; PBMC, peripheral blood mononuclear cell; T:S, ratio of telomere to single-copy gene amounts.
a
Except where otherwise noted. Ns differ between cell types owing to insufficient DNA content in some blood samples. Analyses involving each cell population were conducted with data only from those participants with complete telomere length data for that cell type.
b
”White” category includes white Hispanic. “Other” category includes Asian/Pacific Islander (3%); Native American (<1%); mixed race (3%).
c
Calculated as weight in kilograms divided by height in meters squared.