CDC Monthly Respiratory disease and Influenza Bulletin for Year 2024

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Year 2024-March

In March 2024, National Influenza Surveillance sentinel sites collected 420 samples for Influenza and SARS-CoV-2 virus testing. There were 293 samples from Severe Acute Respiratory Illness (SARI) at nine sites in five provinces (Figure 1). Of all the SARI samples collected for testing, 26 (8.9%) tested positive for influenza virus, of which 23 tested positive for B/Vic, two tested positive for A/H3N2, and one tested positive for A/H1N1pdm. Four (1.4%) SARI samples were positive for SARS-CoV-2. There were 127 samples from Influenza-Like Illness (ILI) Surveillance at 17 sites in 16 provinces (Figure 1). 16 (12.5%) were positive for influenza, out of which 10 tested positive for B/Vic, three tested positive for A/H3N2, and three tested positive for A/H1N1pdm. Two ILI samples (1.5%) were positive for SARS-CoV-2.

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Year 2024-February

In February 2024, National Influenza Surveillance sentinel sites collected 558 samples for Influenza and SARS-CoV-2 virus testing. There were 406 samples from Severe Acute Respiratory Illness (SARI) at 9 sites in 5 provinces (Figure 1). There were 152 samples from Influenza-Like Illness (ILI) Surveillance at 17 sites in 16 provinces (Figure 1). Among 406 SARI specimens, 48 (11.8%) tested positive for influenza virus, of which 40 tested positive for B/Vic, five tested positive for A/H3N2, two tested positive for A/H1N1pdm, and one tested positive for A/H5N1. Of all the SARI samples collected for testing, six (1.5%) were positive for SARS-CoV-2. Of 152 ILI specimens, 27 (17.8%) were positive for influenza, out of which 24 tested positive for B/Vic, and three tested positive for A/H3N2. Seven ILI samples (4.6%) were positive for SARS-CoV-2.

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Year 2024-January

In January 2024, National Influenza Surveillance sentinel sites collected 423 samples for Influenza and SARS-CoV-2 virus testing. There were 324 samples from Severe Acute Respiratory Illness (SARI) at 9 sites in 5 provinces (Figure 1). There were 99 samples from Influenza-Like Illness (ILI) Surveillance at 17 sites in 16 provinces (Figure 1). Among 324 SARI specimens, 22 (6.8%) tested positive for influenza virus, of which 16 tested positive for B/Vic, 5 tested positive for A/H3N2, and 1 tested positive for A/H1N1pdm. Out of all the SARI samples collected for testing, 33 (10.2%) were positive for SARS-CoV-2. Of 99 ILI specimens, 17 (17.2%) were positive for influenza, of which 12 tested positive for B/Vic, and 5 tested positive for A/H3N2. 11 ILI samples (11.1%) were positive for SARS-CoV-2.