Table 3. Replication and virulence of different H5 viruses in ducks.
| Virus | Replication in organs (mean titre)a | Virus shedding on different days post inoculation, positive/total (mean titre: oropharynx/cloaca)b | Death/total | Seroconversion: positive/total (mean HI antibody titre, log2) | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Day 3 | Day 5 | Day 7 | ||||||||||
| Lung | Brain | Inoculated | Contact | Inoculated | Contact | Inoculated | Contact | Inoculated | Contact | Inoculated | Contact | |
| GG/JS/6/2015(H5N1) | 4.8 | 5.6 | / | / | / | / | / | / | 5/5 | 3/3 | / | / |
| WS/HeN/1/2015(H5N1) | 5.0 | 7.2 | 5/5 (3.7/1.3) |
3/3 (2.7/0.9) |
5/5 (2.0/1.5) |
3/3 (3.0/0.9) |
3/3 (1.2/<) |
3/3 (1.6/1.1) |
4/5 | 0/3 | 1/1 (6.0) |
3/3 (3.7) |
| GBHG/QH/9/2015(H5N1) | 6.4 | 3.3 | 5/5 (3.4/0.9) |
3/3 (4.2/2.3) |
0/5 | 3/3 (2.2/0.9) |
0/5 | 0/3 | 0/5 | 0/3 | 5/5 (6.4) |
3/3 (5.0) |
| GP/HuN/14/2015(H5N2) | 5.4 | 4.3 | 5/5 (3.8/1.9) |
3/3 (1.8/1.6) |
5/5 (1.3/0.9) |
3/3 (1.6/1.5) |
0/5 | 0/3 | 0/5 | 0/3 | 5/5 (6.2) |
3/3 (5.3) |
| GP/HuN/13/2015(H5N6) | 4.8 | 5.0 | 5/5 (4.0/2.1) |
3/3 (3.1/2.8) |
5/5 (2.7/2.4) |
3/3 (3.4/1.7) |
/ | 0/3 | 5/5 | 0/3 | / | 3/3 (6.0) |
| CP/HuN/11/2015(H5N6) | 5.6 | 5.3 | 5/5 (3.8/2.9) |
3/3 (4.3/3.9) |
5/5 (2.9/1.9) |
3/3 (1.0/0.9) |
2/4 (1.3/0.9) |
0/3 | 1/5 | 0/3 | 4/4 (6.3) |
3/3 (6.0) |
| CP/HuN/2/2016(H5N6) | 5.8 | 4.8 | 4/4 (4.6/3.2) |
3/3 (5.4/2.4) |
1/3 (1.2/0.9) |
3/3 (4.8/2.7) |
2/2 (1.0/0.9) |
2/2 (1.2/1.4) |
4/5 | 1/3 | 1/1 (7.0) |
2/2 (7.5) |
| GP/HuN/1/2016(H5N6) | 4.3 | 5.0 | 5/5 (4.0/3.0) |
3/3 (3.6/2.8) |
1/4 (0/3.8) |
3/3 (1.2/0.9) |
0/4 | 0/3 | 1/5 | 0/3 | 4/4 (5.3) |
3/3 (5.7) |
| GG/HuN/1/2017(H5N6) | 5.8 | 5.8 | 5/5 (4.9/3.3) |
3/3 (4.8/2.4) |
2/5 (4.4/0.9) |
3/3 (3.1/1.6) |
/ | / | 5/5 | 3/3 | / | / |
| WS/SX/6/2016(H5N8) | 4.8 | 5.8 | 5/5 (4.4/3.3) |
3/3 (4.8/2.0) |
5/5 (1.9/0.9) |
3/3 (2.8/0.9) |
0/5 |
3/3 (1.8/0.9) |
0/5 | 1/3 | 5/5 (4.8) |
2/2 (4.5) |
aViral titre of all ten organs tested were show in supporting Figure 3.
bSwabs of survival ducks on day 9 p.i. were also collected, virus was only detected in one contact duck of the WS/HeN/1/2015(H5N1)-inoculated group, with titres of 1.0 and 0.9 in the oropharynx and cloaca, respectively. /, all ducks died; <, virus was not detected in the cloacal swabs.