Table 2.
Replication of H7N9-RG and H7N9-PBC mouse-passaged viruses in mice. Groups of mice (n = 5) were infected intranasally with 102 PFU of either H7N9-RG mP2 or H7N9-PBC mP2 viruses, blood and tissues were collected on days 3, 6, and 8 post-infection. Viral load was first measured by RT-qPCR detecting the M gene, with mean Ct values reported, and the limit of detection of the assay was 50 genome copies/mL or /g tissue. For all RT-qPCR positive samples, infectious viral loads were determined by TCID50 assay, where x is the number of samples that were RT-qPCR positive, and the mean logTCID50/mL or /g ± standard error of mean is shown. ND = not determined.
| Virus | Sample | Day 3 | Day 6 | Day 8 | |||
|---|---|---|---|---|---|---|---|
|
Mean Ct
(x / 5 mice) |
LogTCID50
per ml or g (n = x) |
Mean Ct
(x / 5 mice) |
LogTCID50
per ml or g (n = x) |
Mean Ct
(x / 5 mice) |
LogTCID50
per ml or g (n = x) |
||
| H7N9-RG mP2 | Blood | 0 | ND | 0 | ND | 0 | ND |
| Heart | 33.5 (2) | (0/2) | 34.6 (1) | (0/1) | 0 | ND | |
| Spleen | 0 | ND | 0 | ND | 0 | ND | |
| Kidney | 0 | ND | 0 | ND | 0 | ND | |
| Intestine | 0 | ND | 0 | ND | 0 | ND | |
| Lung | 24.3 (5) | 3.3 ± 2.7 (3/5) |
18.6 (5) | 6.0 ± 0.5 (5/5) |
27.9 (5) | 1.8 ± 2.3 (2/5) |
|
| Eyes | 0 | ND | 0 | ND | 0 | ND | |
| H7N9-PBC mP2 | Blood | 32.5 (2) | (0/2) | 0 | ND | 27.5 (2) | (0/2) |
| Heart | 30.9 (3) | (0/3) | 31.8 (4) | (0/4) | 33.9 (3) | (0/3) | |
| Spleen | 34.3 (3) | (0/3) | 34.4 (1) | (0/1) | 0 | ND | |
| Kidney | 30.7 (1) | (0/1) | 34.7 (1) | (0/1) | 0 | ND | |
| Intestine | 34.9 (1) | (0/1) | 35.6 (1) | (0/1) | 0 | ND | |
| Lung | 15.7 (5) | 7.3 ± 0.4 (5/5) |
15.6 (5) | 7.1 ± 0.3 (5/5) |
23.3 (5) | 6.2 ± 0.2 (5/5) |
|
| Eyes | 0 | ND | 34.0 (2) | (0/2) | 0 | ND | |