Table 2.
Pathogenicity and transmission of Pakistani H7N3 viruses in chickens
| Transmissiona | Organ Titers | Viral shedding (days) |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| Virus isolate | IVPI (b) | 6-week-old birds | 33-week-old birds | ||||||
| Infected | Contact | Infected | Contact | Kidney | Pancreas | Trachea (d) | Cloaca (d) | ||
| A/Ck/Pak/34668/95 | 2.22 | 2/2 | ND | ND | ND | ND | ND | 5 | 7 |
| A/Ck/Pak/34669/95 | 2.94 | 2/2 | ND | 2/2 | 0/2 | 3.5 | <1 | ND | ND |
| A/Ck/Pak/C1998/98 | 2.79 | 1/2 | 1/2 | ND | ND | ND | ND | 5 | 14 |
| A/Ck/Pak/NARC-68/02 (c) | 2.82 | 2/2 | 0/2 | 2/2 | 2/2 | 6.0 | 1.5 | 5 | 14 |
| A/Ck/Pak/NARC-72/02 (c) | ND | 2/2 | 0/2 | 2/2 | 0/2 | 6.0 | 2.3 | 5 | 7 |
a
Transmission is shown as the number of dead birds/total number of birds per group.
Abbreviations: IVPI, intravenous pathogenicity index; ND, not done
Separate experiments were done for determining IVPI (b); transmission in 6 week and 33 week birds (c) and in studies on virus titers in organs and duration of shedding (d).