TABLE 6.
Amino acid substitutions and frequencies of minor variants observed in ferret nasal wash samples collected during transmission experiments using A/Anhui-Lujiang/39/2018 virus
| Experiment | Animal sourceb |
Amino acid substitutions or variability (>5% cutoff threshold)a
|
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PB2 | PB1 | PA |
NP | NS1 | HA1c
|
HA2 |
||||||
| 563Q | 617D | 532L | 466N | 253I | 115L/I (84/16) | 39A | 78L | 224N/K (85/15) | 75T/N (90/10) | 215S | ||
| Respiratory droplet transmission experiments | ||||||||||||
| Ferret pair 1 | Inoculated (1 dpi) | Q/R (94/6) | D | L | N | I | L/I (89/11) | A | L | N/K (92/8) | T/N (89/11) | S |
| Ferret pair 1 | Contact (7 dpc) | Q | D | L | N | I | L | A | L | N | T | S |
| Ferret pair 2 | Inoculated (1 dpi) | Q | D | L | N | I | L/I (89/10) | A | L | N/K (81/19) | T/N (88/11) | F |
| Ferret pair 2 | Contact (3 dpc) | Q | D | L | N | I | L | A | L | N | T | S |
| Ferret pair 3 | Inoculated (1 dpi) | Q | D | L | N | I | L/I (88/12) | A | L | N/K (92/8) | T/N (86/14) | S |
| Ferret pair 3 | Contact (3 dpc) | Q | D | L | N | I | L | A | L | K/N (53/46) | T | S |
| Ferret pair 4 | Inoculated (1 dpi) | Q | D | L | N | I/T (94/6) | L/I (88/11) | A | L | N/K (84/16) | T/N (88/12) | S |
| Ferret pair 4 | Contact | ND | ND | ND | ND | ND | ND | ND | ND | ND | ND | ND |
| Ferret pair 5 | Inoculated (1 dpi) | Q | D | L | N | I | L | A | L/R (68/31) | N/K (79/21) | T/N (86/14) | S |
| Ferret pair 5 | Contact (5 dpc) | Q | D | S | N | I | L | A | R | N | T | S |
| Ferret pair 6 | Inoculated (1 dpi) | Q | D | L | N | I | L/I (84/16) | A | L | N/K (91/9) | T/N (84/15) | S |
| Ferret pair 6 | Contact (5 dpc) | Q | D | L | N | I | L | S | L | N | T | S |
| Direct contact transmission experiments | ||||||||||||
| Ferret pair 1 | Inoculated (1 dpi) | Q | D | L | N | I | L/I (83/17) | A | L | N/K (87/13) | T/N (88/12) | S |
| Ferret pair 1 | Contact (3 dpc) | Q | D | L | N | I | L/I (82/18) | A | L | N/K (93/7) | T | S |
| Ferret pair 2 | Inoculated (3 dpi) | Q | D | L | N | I | L/I (91/8) | A | L | N/K (74/26) | T/N (92/8) | S |
| Ferret pair 2 | Contact (3 dpc) | Q | D | L | N | I | L/I (92/7) | A | L | N/K (94/6) | T/N (59/40) | S |
| Ferret pair 3 | Inoculated (3 dpi) | Q | D | L | N | I | L/I (88/12) | A | L | N/K (78/21) | T/N (88/11) | S |
| Ferret pair 3 | Contact (3 dpc) | Q | D/G (94/6) | L | N/S (94/6) | I | L | A | L/R (76/23) | K/N (54/45) | T/N (95/5) | S |
This table presents nonsynonymous changes compared to the inoculum. No amino acid changes or variability was detected for PB1-F2, PA-X, NA, MP, and NEP. Nasal wash samples representing peak titers were chosen for analysis. When mixed populations were detected, the percentage of each amino acid present in the sample is specified in parentheses. ND means that the virus was not detected in this animal during the course of the experiment (limit of detection was 101.5 EID50/ml).
dpi, days postinoculation; dpc, days postcontact.
Amino acid positions for HA1 are in H3 numbering.