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Detection of influenza viruses in respiratory specimens in 2025

Detection of influenza viruses in respiratory specimens in 2025

Week
number

Date

No. of specimen tested

 Type A

Type B

Type C

Positive

 % Subtyping
performed		 H1 H3 H5 H7 H9

Positive

%

Lineage determination performed*

No.

%
1 29/12/2024 - 04/01 8424 398 4.72 381 354 27 0 0 0 13 0.15 12 1 0.01
2 05/01 - 11/01 8864 571 6.44 542 509 33 0 0 0 13 0.15 13 0 0.00
3 12/01 - 18/01 9016 699 7.75 665 617 48 0 0 0 19 0.21 19 2 0.02
4 19/01 - 25/01 9353 900 9.62 841 764 77 0 0 0 14 0.15 14 3 0.03
5 26/01 - 01/02 7715 660 8.55 592 545 48 0 0 0 9 0.12 9 1 0.01
6 02/02 - 08/02 10016 918 9.17 837 758 79 0 0 0 29 0.29 29 1 0.01
7 09/02 - 15/02 9196 689 7.49 625 574 51 0 0 0 32 0.35 30 5 0.05
8 16/02 - 22/02 8794 537 6.11 476 450 26 0 0 0 23 0.26 23 1 0.01
9 23/02 - 01/03 8100 367 4.53 329 311 18 0 0 0 45 0.56 43 2 0.02
10 02/03 - 08/03 8236 222 2.70 202 193 9 0 0 0 44 0.53 39 2 0.02
11 09/03 - 15/03 8146 154 1.89 135 124 11 0 0 0 35 0.43 35 2 0.02
12 16/03 - 22/03 7782 107 1.37 93 83 10 0 0 0 46 0.59 46 2 0.03
13 23/03 - 29/03 8620 83 0.96 78 69 9 0 0 0 39 0.45 39 0 0.00
14 30/03 - 05/04 7420 54 0.73 49 40 9 0 0 0 39 0.53 39 0 0.00
15 06/04 - 12/04 8648 41 0.47 33 25 8 0 0 0 32 0.37 32 1 0.01
16 13/04 - 19/04 8507 33 0.39 33 29 4 0 0 0 33 0.39 33 1 0.01
17 20/04 - 26/04 8879 23 0.26 22 18 4 0 0 0 27 0.30 27 0 0.00
18 27/04 - 03/05 8468 35 0.41 30 19 11 0 0 0 26 0.31 25 0 0.00
19 04/05 - 10/05 8819 34 0.39 33 26 7 0 0 0 14 0.16 14 1 0.01
20 11/05 - 17/05 8797 64 0.73 57 53 4 0 0 0 9 0.10 9 2 0.02
21 18/05 - 24/05 8869 34 0.38 32 29 3 0 0 0 27 0.30 27 2 0.02
22 25/05 - 31/05 8238 46 0.56 43 37 6 0 0 0 23 0.28 22 2 0.02
23 01/06 - 07/06 8111 33 0.41 31 25 6 0 0 0 27 0.33 27 2 0.02
24 08/06 - 14/06 7901 45 0.57 41 33 8 0 0 0 14 0.18 14 0 0.00
25 15/06 - 21/06 7487 67 0.89 57 45 12 0 0 0 23 0.31 18 2 0.03
26 22/06 - 28/06 7532 94 1.25 90 64 26 0 0 0 35 0.46 31 0 0.00
27 29/06 - 05/07 7226 128 1.77 123 76 47 0 0 0 39 0.54 39 3 0.04
28 06/07 - 12/07 7497 139 1.85 134 89 45 0 0 0 43 0.57 40 1 0.01
29 13/07 - 19/07 7522 137 1.82 132 97 35 0 0 0 39 0.52 29 4 0.05
30 20/07 - 26/07 7409 163 2.20 153 120 33 0 0 0 39 0.53 38 0 0.00
31 27/07 - 02/08 7764 178 2.29 168 113 55 0 0 0 37 0.48 36 1 0.01
32 03/08 - 09/08 7303 186 2.55 178 79 99 0 0 0 37 0.51 35 3 0.04
33 10/08 - 16/08 7913 261 3.30 252 134 118 0 0 0 37 0.47 37 2 0.03
34 17/08 - 23/08 8047 354 4.40 337 153 184 0 0 0 21 0.26 21 6 0.07
35 24/08 - 30/08 8458 461 5.45 436 172 264 0 0 0 33 0.39 31 1 0.01
36 31/08 - 06/09 7996 484 6.05 457 182 275 0 0 0 29 0.36 26 0 0.00
37 07/09 - 13/09 8194 552 6.74 529 158 371 0 0 0 19 0.23 19 1 0.01
38 14/09 - 20/09 8459 644 7.61 617 135 482 0 0 0 28 0.33 27 1 0.01
39 21/09 - 27/09 7867 684 8.69 649 119 531 0 0 0 17 0.22 14 1 0.01
40 28/09 - 04/10 8287 681 8.22 650 137 513 0 0 0 24 0.29 24 2 0.02
41 05/10 - 11/10 8193 826 10.08 788 115 673 0 0 0 32 0.39 30 2 0.02
42 12/10 - 18/10 8723 827 9.48 797 82 715 0 0 0 20 0.23 19 1 0.01
43 19/10 - 25/10 8126 805 9.91 790 97 693 0 0 0 16 0.20 13 0 0.00
44 26/10 - 01/11 8557 638 7.46 609 72 537 0 0 0 8 0.09 7 2 0.02
45 02/11 - 08/11 8296 541 6.52 520 61 459 0 0 0 14 0.17 14 1 0.01
46 09/11 - 15/11 8283 460 5.55 439 33 406 0 0 0 13 0.16 11 2 0.02
47 16/11 - 22/11 8196 414 5.05 402 20 382 0 0 0 11 0.13 10 0 0.00
48 23/11 - 29/11 8406 487 5.79 471 17 454 0 0 0 5 0.06 0 1 0.01
 
* All belonged to B/Victoria lineage.

Remarks:
1. For specimens received from 10 February 2014 onwards, molecular testing has replaced viral culture. Please interpret the data and trends in light of the enhanced sensitivity of molecular testing, and hence positive detection rates.
2. Figures are subject to minor adjustments.
3. Multiple specimens may have been received for testing from the same patient.
4. As a result of disruptions in laboratory testing from early 2020 to early 2023, please interpret the data with caution.