Table 1. Influenza virus detections in sentinel and non-sentinel source specimens by type and subtype cumulatively, EU/EEA, weeks 40/2023–9/2024 (n = 154,718).
| Sentinel | Non-sentinel | |||
|---|---|---|---|---|
| Detections by virus (sub)type | n | % | n | % |
| Influenza A | 12,397 | 95.7a | 138,295 | 97.6a |
| A(H1)pdm09 | 8,296 | 79.5b | 22,167 | 73.4b |
| A(H3) | 2,136 | 20.5b | 8,038 | 26.6b |
| A not subtyped | 1,965 | NA | 108, 090 | NA |
| Influenza B | 561 | 4.3a | 3,465 | 2.4a |
| B/Victoria lineage | 256 | 100.0c | 553 | 100.0a |
| B/Yamagata lineage | 0 | 0c | 0 | 0c |
| B Unknown lineage | 305 | NA | 2,912 | NA |
|
Total detections
(total tested) |
12,958
(66,596) |
19.5 |
141,760
(1,168,394) |
12.1 |
| Antigenic characterisations | n | % | ||
| Influenza A | ||||
| A(H1)pdm09 | 512 | 100.0 | ||
| 5a.2a A/Sydney/5/2021-liked | 262 | 51.2 | ||
| 5a.2a.1 A/Victoria/4897/2022-likee,f | 248 | 48.4 | ||
| 5a.2a.1 A/Wisconsin/67/2022-likee,f | 2 | 0.4 | ||
| A(H3) | 103 | 100.0 | ||
| 2a A/Darwin/9/2021-liked,e,g,h | 76 | 73.8 | ||
| 2a.3a.1 A/Thailand/8/2022-likef | 24 | 23.3 | ||
| Not categorised | 3 | 2.9 | ||
| Influenza B | ||||
| B/Victoria lineage | 60 | 100.0 | ||
| V1A.3a.2 B/Austria/1359417/2021-liked,e,f,g,h | 58 | 96.7 | ||
| Not categorised | 2 | 3.3 | ||
| Phylogenetic analysisi | n | % | ||
| Influenza A | ||||
| A(H1)pdm09 | 1,815 | 100.0 | ||
| 5a.2a (C.1) | 1,029 | 56.7 | ||
| 5a.2a + T216A (C.1.7) | 54 | 3.0 | ||
| 5a.2a.1 (C.1.1) | 22 | 1.2 | ||
| 5a.2a.1 + T216A (C.1.1.1) | 710 | 39.1 | ||
| A(H3) | 639 | 100.0 | ||
| 2a.3a (G.1.3.1) | 10 | 1.6 | ||
| 2a.3a.1 (J) | 50 | 7.8 | ||
| 2a.3a.1 + I25V (J.1) | 212 | 33.2 | ||
| 2a.3a.1 + N122D, K276E (J.2) | 346 | 54.1 | ||
| 2a.3a.1 Q173R, K276E (J.4) | 20 | 3.1 | ||
| 2a.3b (G.1.3.2) | 1 | 0.2 | ||
| Influenza B | ||||
| B/Victoria lineage | 90 | 100.0 | ||
| V1A.3a.2 (C.2) | 1 | 1.1 | ||
| V1A.3a.2 (C.3) | 2 | 2.2 | ||
| V1A.3a.2 (C.5) | 9 | 10.0 | ||
| V1A.3a.2 (C.5.1) | 35 | 38.9 | ||
| V1A.3a.2 (C.5.6) | 14 | 15.6 | ||
| V1A.3a.2 + E128G (C.5.7) | 29 | 32.2 | ||
EEA: European Economic Area; EU: European Union; NA: not applicable; WHO: World Health Organization.
a Proportion of influenza A or B type.
b Proportion of influenza A subtypes.
c Proportion of B virus lineages.
d WHO-recommended vaccine virus for the 2023 southern hemisphere influenza season.
e WHO-recommended vaccine virus for the 2023/24 northern hemisphere influenza season.
f WHO-recommended vaccine virus for the 2024 southern hemisphere influenza season.
g WHO-recommended vaccine virus for the 2022 southern hemisphere influenza season.
h WHO-recommended vaccine virus for the 2022/23 northern hemisphere influenza season.
i For the phylogenetic analysis section, subclades in brackets are defined through Nextstrain [4].