Table II.
Effects of different pH conditions on infectivity of severe acute respiratory syndrome coronavirus-2a
| pH | Day 1 (log10 reduction ±SD) | Day 3 (log10 reduction ±SD) | Day 6 (log10 reduction ±SD) |
|---|---|---|---|
| 2 | Negative (6.50±0.00) | Negative (6.50±0.00) | ND |
| 3 | Negative (6.50±0.00) | Negative (6.50±0.00) | ND |
| 4 | Positive (2.67±0.29) | Negative (6.50±0.00) | Negative (6.50±0.00) |
| 5 | Positive (1.08±0.52) | Positive (2.33±0.29) | Positive (3.50±0.50) |
| 6 | Positive (1.00±0.50) | Positive (1.67±0.58) | Positive (4.10±0.85) |
| 7 | Positive (0.67±0.29) | Positive (1.50±0.50) | Positive (2.90±0.96) |
| 8 | Positive (1.23±0.25) | Positive (2.73±0.64) | Positive (3.92±0.63) |
| 9 | Positive (1.50±0.87) | Positive (3.23±0.68) | Positive (5.33±0.58) |
| 10 | Positive (2.40±0.36) | Positive (5.13±0.40) | Negative (6.50±0.00) |
| 11 | Positive (3.00±0.70) | Negative (6.50±0.00) | Negative (6.50±0.00) |
| 12 | Negative (6.50±0.00) | Negative (6.50±0.00) | ND |
| 13 | Negative (6.50±0.00) | Negative (6.50±0.00) | ND |
Positive, culture positive; negative, culture negative; ND, not done; SD, standard deviation.
a
Include untreated virus stock solution as the viral load for the positive control median tissue culture infectious dose/mL=6.50±0.61. All tests were neutralized before testing and performed in triplicate.