Table 3 Association between selected factors and latent as well as incubation periods using univariate AFT model
| Â | Latent period | Â | Incubation period | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Delta (672) | Â | Omicron (885) | Â | Delta (405) | Â | Omicron (420) | |||||
exp (\( \varvec{\beta }\)) (95%CI) | p value | Â | exp (\( \varvec{\beta }\)) (95%CI) | p value | Â | exp (\( \varvec{\beta }\)) (95%CI) | p value | Â | exp (\( \varvec{\beta }\)) (95%CI) | p value | |
Sex | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Male | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |
Female | 1.02 (0.92 ~ 1.13) | 0.735 |  | 0.98 (0.89 ~ 1.09) | 0.760 |  | 1.01 (0.89 ~ 1.13) | 0.941 |  | 0.98 (0.88 ~ 1.08) | 0.633 |
Age | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
0 ~ 17 | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |
18 ~ 49 | 0.76 (0.64 ~ 0.91) | 0.002 |  | 0.74 (0.65 ~ 0.84) | < 0.001 |  | 0.68 (0.56 ~ 0.83) | < 0.001 |  | 0.80 (0.70 ~ 0.92) | 0.002 |
50~ | 0.95 (0.81 ~ 1.11) | 0.500 |  | 1.02 (0.88 ~ 1.18) | 0.805 |  | 0.86 (0.71 ~ 1.04) | 0.128 |  | 0.97 (0.81 ~ 1.16) | 0.733 |
Vaccination history | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Unvaccinated | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |
Partially vaccinated | 0.96 (0.84 ~ 1.09) | 0.492 |  | 1.02 (0.75 ~ 1.40) | 0.900 |  | 0.92 (0.80 ~ 1.06) | 0.229 |  | 0.94 (0.70 ~ 1.25) | 0.676 |
Fully vaccinated | 0.91 (0.80 ~ 1.03) | 0.121 |  | 1.10 (0.90 ~ 1.33) | 0.357 |  | 0.88 (0.77 ~ 1.01) | 0.070 |  | 1.05 (0.87 ~ 1.27) | 0.584 |
Booster | ·· | ·· |  | 0.97 (0.80 ~ 1.18) | 0.762 |  | ·· | ·· |  | 1.01 (0.84 ~ 1.22) | 0.914 |
Clinical severity | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
Asymptomatic | 1 (ref) | ·· |  | 1 (ref) | ·· |  | NA | NA |  | NA | NA |
Mild | 1.40 (0.92 ~ 2.12) | 0.112 |  | 1.05 (0.93 ~ 1.19) | 0.409 |  | 1 (ref) | ·· |  | 1 (ref) | ·· |
Moderate/Severe/Critical | 1.30 (0.87 ~ 1.93) | 0.204 |  | 1.09 (0.92 ~ 1.29) | 0.317 |  | 0.98 (0.83 ~ 1.16) | 0.831 |  | 1.06 (0.90 ~ 1.24) | 0.489 |
Number of infectors | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
> 1 | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |
= 1 | 0.92 (0.82 ~ 1.04) | 0.184 |  | 1.04 (0.94 ~ 1.14) | 0.471 |  | 0.92 (0.81 ~ 1.05) | 0.229 |  | 1.07 (0.97 ~ 1.19) | 0.186 |
Exposure window | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
≤ 3 days | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |
> 3 days | 1.07 (0.96 ~ 1.19) | 0.227 |  | 1.54 (1.37 ~ 1.73) | < 0.001 |  | 1.05 (0.94 ~ 1.19) | 0.388 |  | 1.54 (1.38 ~ 1.73) | < 0.001 |
Shedding window | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
≤ 3 days | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |
> 3 days | 0.79 (0.70 ~ 0.89) | < 0.001 |  | 0.85 (0.70 ~ 1.02) | 0.086 |  | 0.95 (0.85 ~ 1.06) | 0.376 |  | 1.21 (1.07 ~ 1.38) | 0.002 |
Omicron sublineages | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
BA.1 | NA | NA |  | 1 (ref) | ·· |  | NA | NA |  | 1 (ref) | ·· |
BA.2 | NA | NA |  | 0.94 (0.83 ~ 1.05) | 0.262 |  | NA | NA |  | 0.98 (0.86 ~ 1.12) | 0.759 |
Comorbidity | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â | Â |
No | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |  | 1 (ref) | ·· |
Yes | 1.00 (0.89 ~ 1.12) | 0.954 |  | 1.10 (0.89 ~ 1.35) | 0.364 |  | 0.98 (0.86 ~ 1.11) | 0.695 |  | 1.07 (0.84 ~ 1.35) | 0.597 |