Reagent update
Current availability from MHRA of candidate influenza vaccine viruses, SRD reagents and neuraminidase reagents for use in the 2026 southern hemisphere season and in the 2025-26 northern hemisphere season (see below for pricing information).
More information can be found in the Influenza Resource Centre pages
Update 167 - 13 April 2026
Candidate influenza viruses for use in the northern hemisphere 2026-271
Candidate influenza vaccine viruses
|
NIBSC code
|
|
H1N1
|
|
|
A/Switzerland/6849/2025
|
25/234
|
|
IVR-278 reassortant derived from A/Switzerland/6849/2025
|
25/240
|
|
A/Missouri/11/2025
|
25/236
|
|
IVR-279 reassortant derived from A/Missouri/112025
|
25/242
|
|
H3N2
|
|
|
A/Darwin/1454/2025
|
25/296
|
|
IVR-283 reassortant derived from A/Darwin/1454/2025
|
25/304
|
|
A/Darwin/1499/2025
|
25/318
|
|
IVR-284 reassortant derived from A/Darwin/1499/2025
|
25/306
|
|
A/Michigan/105/2025
|
25/298
|
|
IVR-285 reassortant derived from A/Michigan/105/2025
|
25/324
|
|
SAN-049A reassortant derived from A/Michigan/105/2025
|
25/326
|
|
CNIC-2601 reassortant derived from (A/Sichuan-Pingshan/323/20250
|
25/292
|
|
CNIC-2602A reassortant derived from (A/Shanghai-Huangpu/12925/2025)
|
25/294
|
|
B (Victoria lineage)
|
|
|
B/Toyko/EIS13-175/2025
|
25/300
|
|
B/Tokyo/EIS-011/2025
|
25/302
|
|
B/Perth/115/2025
|
25/328
|
1 Recommended composition of influenza virus vaccines for use in the 2026-2027 northern hemisphere influenza season
Access To B/Yamagata lineage viruses is currently restricted.
Please contact Othmar.Engelhardt@mhra.gov.uk and Jason.Long@mhra.gov.uk
SRD reagents for use in the northern hemisphere 2026-27 1
Reagents for influenza vaccine standardisation
|
NIBSC code
|
|
H1N1
|
|
|
A/Switzerland/6849/2025 (IVR-278) antigen
|
25/222
|
|
A/Missouri/11/2025 (IVR-279) antigen
|
25/320
in preparation
|
|
A/Missouri/11/2025 - like antiserum
|
25/224
|
|
H3N2
|
|
|
A/Michigan/105/2025 (IVR-285) antigen
|
26/100
in preparation
|
|
A/Michigan/105/2025 (SAN-049A) antigen
|
26/102
in preparation
|
|
A/Darwin/1454/2025 – like –antiserum
|
26/108
in preparation
|
|
B (Victoria lineage)
|
|
|
B/Tokyo/EIS13-175/2025antigen
|
26/104
in preparation
|
|
B/Tokyo/EIS13-175/2025 – like antiserum
|
26/110
in preparation
|
1 Recommended composition of influenza virus vaccines for use in the 2026-2027 northern hemisphere influenza season
B Yamagata reagents available
Reagents for influenza vaccine standardisation
|
NIBSC code
|
|
B (Yamagata lineage)
|
|
|
B/Phuket/3073/2013 antigen
|
21/136
24/182
|
|
B/Utah/9/2014 (cell derived) antigen
|
15/100
|
|
B/Singapore/INFTT-16-0610/2016 (cell derived) antigen
|
19/308
|
|
B/Phuket/3073/2013 - like antiserum
|
22/132
|
Neuraminidase reagents in use
Neuraminidase reagents
|
NIBSC code
|
|
N1
|
|
|
NA antiserum prepared from A/California/7/2009
|
10/218
|
|
NA antiserum prepared from A/New Caledonia/20/99
|
04/230
|
|
NA antiserum prepared from A/Victoria/4897/2022
|
23/208
|
|
N2
|
|
NA antiserum prepared from A/Victoria/361/2011
|
14/144
|
|
NA antiserum prepared from A/South Australia/34/2019
|
19/320
|
|
B
|
|
NA antiserum prepared from B/Jiangsu/10/2003
|
04/228
|
|
NA antiserum prepared from B/Malaysia/2506/2004
|
05/252
|
|
NA antiserum prepared from B/Phuket/3073/2013
|
21/322
|
Candidate influenza viruses for use in the southernhemisphere 20262
Candidate influenza vaccine viruses
|
NIBSC code
|
|
H1N1
|
|
|
A/Switzerland/6849/2025
|
25/234
|
|
IVR-278 reassortant derived from A/Switzerland/6849/2025
|
25/240
|
|
A/Missouri/11/2025
|
25/236
|
|
IVR-279 reassortant derived from A/Missouri/11/2025
|
25/242
|
|
SAN-046 reassortant derived from A/Missouri/11/2025
|
25/282
|
|
H3N2
|
|
|
A/Singapore/GP20238/2024
|
25/232
|
|
IVR-277 reassortant derived from A/Singapore/GP20238/2024
|
25/238
|
|
A/Valladolid/1187/2025
|
25/244
|
|
B (Victoria lineage)
|
|
|
B/Austria/1359417/2021
|
25/280
|
|
BVR-26 reassortant derived from B/Austria/1359417/2021
|
25/264
|
|
BX-107A reassortant derived from B/Austria/1359417/2021
|
22/134
|
|
B/Michigan/01/2021
|
21/244
|
|
B/Singapore/WUH4618/2021
|
21/242
|
|
B/Guangdong-Zhenjiang/1516/2021
|
21/388
|
2 Recommended composition of influenza virus vaccines for use in the 2026 southern hemisphere influenza season
Access To B/Yamagata lineage viruses is currently restricted.
Please contact Othmar.Engelhardt@mhra.gov.uk and Jason.Long@mhra.gov.uk
SRD reagents for use in the southern hemisphere 20262
Reagents for influenza vaccine standardisation
|
NIBSC code
|
|
H1N1
|
|
|
A/Switzerland/6849/2025 (IVR-278) antigen
|
25/222
|
|
A/Missouri/11/2025 - like antiserum
|
25/224
|
|
H3N2
|
|
|
A/Singapore/GP20238/2024 (IVR-277) antigen
|
25/220
|
|
A/Singapore/GP20238/2024 - like antiserum
|
25/226
|
|
B (Victoria lineage)
|
|
|
B/Austria/1359417/2021 (BVR-26) antigen
|
24/180
|
|
B/Michigan/01/2021 antigen
|
21/330
|
|
B/Singapore/WUH4618/2021 (cell derived) antigen
|
23/268
|
|
B/Austria/1359417/2021 - like antiserum
|
24/118
|
2 Recommended composition of influenza virus vaccines for use in the 2026 southern hemisphere influenza season
Pricing information
Viruses are free of charge (normally a maximum of two vials per recipient), but customers are expected to pay shipping and packing costs. Reagents for Single Radial Diffusion assay are subject to a handling fee as stated on the product information page, plus shipping and packing costs. Approved National Control Laboratories for human health are exempt from the handling fee.
Calibration of Reagents for Influenza vaccine standardisation
Reference antigens and antiserum reagents for the standardization of vaccines are produced by the following WHO laboratories:
Essential Regulatory Laboratories (ERL)
- Medicines and Healthcare products Regulatory Agency (MHRA), UK
- Center for Biologics Evaluation and Research (CBER), USA
- National Institute for Infectious Disease (NIID), Japan
- Therapeutic Goods Administration (TGA), Australia