As of 8 January 2024, influenza activity continued to increase in the temperate Northern Hemisphere, mainly in parts of North America, Europe and Central Asia. Increased influenza activity was observed in both North America and Europe, with A(H1N1)pdm09 predominating. In the United States of America, influenza-like illness (ILI) activity increased in all age groups but was lower compared to last season’s peak (2022-2023) and that of 2019-2020. Influenza A(H3N2) accounted for the majority of subtyped cases in the Republic of China followed by a smaller but increased proportion of Influenza B-Victoria lineage viruses.
In Southern Africa, influenza activity was below the seasonal threshold with a few influenza B viruses detected in recent weeks. However, clinicians are advised to have a high index of suspicion for influenza in travelers presenting with respiratory illness who have travelled from the Northern Hemisphere.
More information about the influenza activity in the Northern Hemisphere can be accessed through the WHO Influenza Update No462 report here
