Table 1 Molecular analysis of the A/Taiwan/1/2021(H1N2)v virus

PB2

627

E

K

E

Replication ability [26]

701

D

N

D

Nuclear Import [26]

PB1

99

H

Y

H

Increased transmission in ferret [27]

PA

336

L

M

M

Increased polymerase activity in mice [28]

HA

(H3 numbering)

Cleavage site

Single basic aa

Multiple basic aa

PSIQSR/GLF

high pathogenesis in poultry [29]

190

E

D

D

Increased binding to human-type influenza receptor [30, 31]

225

G

D

D

Increased binding to human-type influenza receptor [30, 31]

226

Q

L

Q

Increased binding to human-type influenza receptor [30, 32]

228

G

S

G

Increased binding to human-type influenza receptor [30, 32, 33]

NA

(N2 numbering)

119

E

V

E

Resistance to oseltamivir and zanamivir [34]

222

I

L

I

Resistance to oseltamivir and zanamivir [35]

224

R

K

R

Resistance to oseltamivir and zanamivir [36]

292

R

K

R

Resistance to oseltamivir and zanamivir [34]

M2

31

S

N

N

Amantadine resistance [37]

NS1

42

P

S

A

Increased pathogenesis in mice [38]

92

D

E

D

Altered virulence in mice [39]

205

N

S

N

Altered antiviral response in host [40]