Global variability of influenza activity and virus subtype circulation from 2011 to 2023

BackgroundAlthough decreased influenza activity has been reported in many countries during the COVID-19 pandemic, it remains unknown how global influenza activity has changed. We described the global variability of influenza activity and virus subtype circulation from 2011 to 2023 to prepare for the...

Full description

Saved in:
Bibliographic Details
Published in:BMJ open respiratory research 2023-07, Vol.10 (1), p.e001638
Main Authors: Zheng, Luyan, Lin, Yushi, Yang, Jing, Fang, Kailu, Wu, Jie, Zheng, Min
Format: Article
Language:English
Subjects:
COVID-19
Disease transmission
Epidemics
Fatalities
Influenza
Pandemics
Respiratory Epidemiology
Respiratory Infection
Seasons
Software
Viruses
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:BackgroundAlthough decreased influenza activity has been reported in many countries during the COVID-19 pandemic, it remains unknown how global influenza activity has changed. We described the global variability of influenza activity and virus subtype circulation from 2011 to 2023 to prepare for the potential influenza outbreak with the control of the COVID-19 pandemic.MethodsInfluenza virological surveillance data between 2011 and 2023 were obtained from the WHO-FluNet database. We first calculated and compared the influenza activity before and during the COVID-19 pandemic. For countries whose influenza activity has recovered, we also described changes in the duration of influenza epidemics. We then determined the proportion of influenza cases caused by the different influenza virus types.ResultsIn total, 73 countries with 2.17 million influenza cases were included. In the early stage of the COVID-19 pandemic, decreased influenza activity was observed in all WHO regions. In 2022 and 2023, rebound in influenza activity was observed in all WHO regions, especially in Western Pacific Region. At the same time, a change in the duration of the influenza epidemic was observed in several Southern Hemisphere countries. Moreover, in all WHO regions, few B/Yamagata viruses were detected during the COVID-19 pandemic.ConclusionsLack of exposure to influenza will diminish population immunity and increase the severity of large epidemics on a future global resurgence. Ongoing monitoring of the changes in the duration of the influenza epidemic and circulation subtypes should be the focus of future work.
ISSN:2052-4439
2052-4439
DOI:10.1136/bmjresp-2023-001638