Group 1: Influenza Surveillance Data - The positive rate of influenza virus detection in southern provinces increased to 24.5%, while in northern provinces it reached 32.8%, resulting in a national average of 28.6%[9] - A total of 171 influenza-like illness (ILI) outbreaks were reported nationwide during the 52nd week of 2024[12] - The ILI percentage in southern provinces was reported at 5.7%, up from 4.7% the previous week, and higher than the 2021 level of 4.1%[7] - In northern provinces, the ILI percentage was 7.2%, an increase from 6.4% the previous week, and higher than the 2021-2023 levels[15] Group 2: Pathogen Monitoring - From April 1 to December 29, 2024, 1844 strains (97.0%) of A(H1N1)pdm09 were similar to A/Victoria/4897/2022, while 392 strains (56.0%) of A(H3N2) were similar to A/Thailand/8/2022[4] - Among 141 A(H1N1)pdm09 strains analyzed, 100% were found to be similar to A/Victoria/4897/2022[11] - Resistance monitoring indicated that 88 strains (95.7%) of A(H1N1)pdm09 were sensitive to neuraminidase inhibitors, while 4 strains (4.3%) showed reduced sensitivity[31] Group 3: Outbreak Overview - Nationwide, 684 ILI outbreaks were reported from April 1 to December 29, 2024, with 520 attributed to A(H1N1)pdm09[34] - The southern provinces reported 388 outbreaks, significantly lower than the 2309 outbreaks reported in the same period of 2023[34] - The northern provinces reported 296 outbreaks, also lower than the 468 outbreaks reported in 2023[34] Group 4: Global Influenza Activity - In the northern hemisphere, influenza activity has increased in several regions, particularly with A(H1N1)pdm09 and B type viruses[44] - The World Organization for Animal Health reported 21 high-pathogenic avian influenza outbreaks globally during the week of December 22-28, 2024[40]
流感监测周报2024年第52周 总第837期
Century Securities·2025-01-06 07:14