We were spared influenza co‐circulating with SARS‐CoV‐2 since 2020, but that is likely to change
Influenza seasons in temperate Australia typically begin in June, peak in August and trail off by October, with some variability from year to year, whereas influenza activity occurs in two periods in the tropical north.1 Since the global spread of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) in early 2020, we have not experienced seasonal influenza in Australia; effectively, we were spared influenza circulating concurrently with SARS‐CoV‐2 in 2020 and 2021. Globally, there was virtually no influenza reported after mid‐March in 2020, but influenza activity was reported in 2021 from a few countries (Box, A, C and D), most notably in western Africa and the Indian subcontinent, and the number of cases was small. Several factors, which occurred variably in different countries and even within countries, contributed to the absence of influenza activity during the coronavirus disease 2019 (COVID‐19) pandemic. These included restrictions on international travel; mandatory quarantine for returned travellers; working from home; school closures; social and public health measures, such as mask wearing, physical distancing and hand hygiene; and, potentially, viral interference.2 These factors are not specific to influenza, as evidenced by the fact that the other major seasonal respiratory virus, respiratory syncytial virus, also did not circulate in its normal autumn–winter pattern in Australia in 2020 but re‐emerged in spring 2020 in some states (New South Wales and Western Australia) and in summer 2021 in others (Victoria and Queensland).3
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The Melbourne WHO Collaborating Centre for Reference and Research on Influenza is supported by the Australian Government Department of Health.
No relevant disclosures.