TABLE 1.
Summary of testing results for 19 cloacal swab field samples and inoculum samples included in this study. Cloacal swab field samples refers to the samples that were collected from Mallards (Anas platyrhynchos) in Minnesota, frozen at −80 C, thawed, and tested by virus isolation (VI) and real-time reverse-transcription PCR (RRT-PCR). Inoculum samples refer to the cloacal swab field samples after they were refrozen at −80 C and thawed one additional time and the residual cloacal swab medium was diluted to 2.5 mL.
| Sample identification | Cloacal swab field samples testing |
Inoculum concentration testing |
Inoculum inoculation testing |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Mallards | |||||||||||
| VI (Eggs) | Postinoculation VI |
14 DPI serology | Mallard infection summary based on VI and serology | ||||||||
| 2 DPIc |
4 DPI |
||||||||||
| VI | RRT-PCR (Ct valuea) |
Titer (log10EID50b) |
RRT-PCR (Ct value) |
OP | Cl | OP | Cl | ||||
| A/Mallard/MN/AI10-2106/10 (H4N6) | + | 29.93 | 3.8 | 27.58 | 5/5 | 4/5 | 5/5 | 2/5 | 5/5 | 5/5 | 5/5 |
| A/Mallard/MN/AI09-3094/09 (H6N1) | + | 28.65 | 2.3 | 32.88 | 5/5 | 1/5 | 1/5 | 0/5 | 2/5 | 1/5 | 2/5 |
| A/Mallard/MN/AI09-2434/09 (H3N8) | + | 26.16 | 1.9 | 26.16 | 5/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| A/Mallard/MN/Sg-00929/08 (H3N8) | + | 22.37 | 1.5 | 29.11 | 5/5 | 5/5 | 5/5 | 5/5 | 5/5 | 5/5 | 5/5 |
| A/Mallard/MN/AI09-2684/09 (H6N1) | + | 29.25 | 0.9 | 28.48 | 5/5 | 5/5 | 5/5 | 3/5 | 5/5 | 5/5 | 5/5 |
| A/Mallard/MN/AI09-3100/09 (H6N3) | + | 28.65 | 0.9 | 27.91 | 3/5 | 4/5 | 5/5 | 2/5 | 5/5 | 5/5 | 5/5 |
| A/Mallard/MN/Sg-00680/08 (H8N4) | + | 22.89 | <0.9d | 29.85 | 4/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| A/Mallard/MN/Sg-00570/08 (H8N4) | + | 22.92 | <0.9 | 30.41 | 1/5 | 2/5 | 3/5 | 0/5 | 5/5 | 5/5 | 5/5 |
| A/Mallard/MN/AI09-2855/09 (H4N8) | + | 30.19 | <0.9 | 29.66 | 2/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| A/Mallard/MN/AI09-2564/09 (H3N8) | + | 29.71 | <0.9 | 27.84 | 5/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| A/Mallard/MN/AI10-2050/10 (H11N9) | + | 29.16 | <0.9 | 28.07 | 5/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| A/Mallard/MN/Sg-00684/08 (H8N8) | + | 26.08 | -e | 34.31 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| A/Mallard/MN/Sg-00927/08 (H6N1) | + | 29.91 | - | 39.28 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| A/Mallard/MN/Sg-00932/08 (H6N1) | + | 25.96 | - | 35.57 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| AI07-5395 | − | 28.45 | - | 29.07 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| AI07-4041 | − | 33.85 | - | 34.83 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| AI07-2844 | − | 34.98 | - | 35.64 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| AI07-3907 | − | 35.42 | - | 36.28 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
| AI08-3605 | − | - | - | - | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 | 0/5 |
a
Ct = cycle threshold.
b
Titer in 0.2 mL inoculated into embryonating chicken eggs and Mallards.
c
DPI = day postinoculation.
d
Virus isolation positive, but below the limit of detection with viral titration.
e
[−] = negative result.