Table 4.
Vaccine efficacy based on symptomatic COVID-19 infection in both scenarios: without censoring for COVID-19 vaccination and with censoring for COVID-19 vaccination.
| Scenario | All | Unvaccinated | Revaccinated with BCG |
|---|---|---|---|
| COVID-19 – without censoring for COVID-19 vaccination | |||
| Number of COVID-19 cases, n | 16 | 9 | 7 |
| Cumulative incidence. n/total (%) | 16/131 (12.2) | 9/67 (13.4) | 7/64 (10.9) |
| Number censored, n (%) | 115 (87.8) | 58 (86.6) | 57 (89.1) |
| VE based on HR (95.0% CI)* | 28.0 (-98.0 to 74.0) | ||
| Person-Years | 59.8 | 30.4 | 29.4 |
| IR per 100 Person-Years (95.0% CI) | 26.8 (15.3-43.4) | 29.6 (13.5-56.2) | 23.8 (9.6-49.1) |
| VE based on IRR (95.0% CI)† | 30.0 (-93.0 to 76.0) | ||
| COVID-19 – with censoring for COVID-19 vaccination | |||
| Number of COVID-19 cases, n | 14 | 7 | 7 |
| Cumulative incidence, n/total (%) | 14/131 (10.7) | 7/67 (10.4) | 7/64 (10.9) |
| Number censored, n (%) | 117 (89.3) | 60 (89.6) | 57 (89.1) |
| VE based on HR (95.0% CI)* | 8.0 (-173.0 to 69.0) | ||
| Person-Years | 42.2 | 21.2 | 21.0 |
| IR per 100 Person-Years (95.0% CI) | 33.2 (18.1-55.7) | 33.0 (13.3-68.0) | 33.3 (13.4-68.7) |
| VE based on IRR (95.0% CI)† | 16.0 (-155.0 to 72.0) |
Symptomatic COVID-19 defined as the presence of RT-PCR or IgM or IgG serology positive test and presence of flu-like symptoms. IRR, incidence rate ratio; HR=hazard ratio; VE, vaccine efficacy; CI, confidence interval. *Vaccine efficacy based on 1-HR obtained in Cox proportional model adjusted for age and sex; †Vaccine efficacy based on 1-IRR obtained in Poisson model adjusted for age and sex, with the natural logarithm (log[n]) of time at risk as offset variable.