Nisar Nadia, Badar Nazish, Safdar Inayah
Public Health Laboratories Division National Institute of Health, Islamabad, Pakistan.
PLoS One. 2025 Jun 4;20(6):e0323465. doi: 10.1371/journal.pone.0323465. eCollection 2025.
The year 2021 witnessed a decline in seasonal influenza cases across Southeast Asia and the broader Asian region. However, a sudden surge in influenza cases during 2022-2023 necessitates comprehensive exploration and analysis to inform future prediction models.
Our study aims to evaluate the disease burden of influenza in Asian countries post-COVID-19, while comparing seasonal variations to the pre-pandemic influenza patterns.
We conducted an extensive analysis of data spanning from January 2017 to September 2023 across ten Asian countries, categorizing them into three WHO regions. Data was sourced from the WHO Flunet system, falling under the purview of the WHO Global Influenza Program.
In conclusion, influenza epidemiology during the inter-pandemic period is characterized by seasonality influenced by factors such as population contact patterns, virus survival, and host immunity. The year 2020 witnessed a global decrease in influenza circulation due to widespread lockdowns and travel restrictions. However, a resurgence was observed in late 2021, notably with out-of-season activity in the Southern Hemisphere. Our analysis based on reviews indicates a probable significant increase in influenza cases in the upcoming seasons. To address this, the implementation of influenza vaccination programs and the promotion of vaccination for both children and adults are essential measures to alleviate the dual burden of influenza in the post-COVID era.
2021年东南亚及更广泛的亚洲地区季节性流感病例有所下降。然而，2022 - 2023年流感病例突然激增，因此有必要进行全面的探索和分析，为未来的预测模型提供依据。
我们的研究旨在评估新冠疫情后亚洲国家流感的疾病负担，同时将季节性变化与疫情前的流感模式进行比较。
我们对2017年1月至2023年9月期间十个亚洲国家的数据进行了广泛分析，这些国家分为三个世卫组织区域。数据来源于世卫组织流感监测网络系统，属于世卫组织全球流感计划的范畴。
总之，大流行间期的流感流行病学具有季节性特征，受人口接触模式、病毒存活和宿主免疫力等因素影响。2020年，由于广泛的封锁和旅行限制，全球流感传播有所减少。然而，2021年末出现了反弹，尤其是南半球出现了非季节性活动。我们基于综述的分析表明，在即将到来的季节中流感病例可能会大幅增加。为应对这一情况，实施流感疫苗接种计划以及推广儿童和成人疫苗接种是减轻新冠后时代流感双重负担的重要措施。
