Table 2. Genetic risk characteristics of influenza A virus subtype H7N3 isolates, Cambodia*.
| Gene segment and risk factor |
Amino acid change |
Isolates in Cambodia |
Conclusions† |
Reference |
|---|---|---|---|---|
| PB2 | ||||
| Mammalian host range marker and increased viral pathogenicity |
E627K | E | Avian specificity |
(9) |
| D701N |
D |
|||
| HA | ||||
| Multibasic cleavage site causing increased pathogenicity | Multibasic | PEPPKGR/GLF | Monobasic | (10) |
| Increased mammalian receptor specificity |
Q226L‡ | Q | Avian specificity |
(11) |
| G228S‡ |
G |
|||
| NA | ||||
| Resistance to NA inhibitor antivirals |
H275Y§ | H | Sensitive to oseltamivir |
(12) |
| E119K¶ | E | |||
| R292K |
R |
|||
| MP | ||||
| Resistance to M2 inhibitor antivirals | L26F | Q | Sensitive to M2 inhibitors | (13) |
| V27A | R | |||
| A30T | D | |||
| S31N | V | |||
| G34E | G | |||
*HA, hemagglutinin; MP, matrix protein; MP2, matrix protein 2; NA, neuraminidase; PB2, polymerase basic protein 2. †Receptor binding specificity and antiviral sensitivity is predicted based on sequence information and has not been experimentally confirmed. ‡H3 numbering. §N1 numbering. ¶N2 numbering.