Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea; Graduate School of Public Health, Korea University, Seoul, Republic of Korea; Transdisciplinary Major in Learning Health Systems, Department of Healthcare Sciences, Graduate School, Korea University, Seoul, Republic of Korea.
Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea; Graduate School of Public Health, Korea University, Seoul, Republic of Korea.
Int J Infect Dis. 2021 Jul;108:109-111. doi: 10.1016/j.ijid.2021.05.039. Epub 2021 May 19.
While the reduction in influenza cases in the Northern hemisphere in 2020 has been widely reported, the influenza transmission dynamics in the Southern hemisphere remain uncharacterized.
This study analysed the change in influenza-positive proportion (IPP) between 2010-2019 and 2020 in countries in the Southern hemisphere with ≤40% missing IPP data in FluNet to assess how coronavirus disease 2019 (COVID-19) relates to influenza activity. The analysis considered the incidence of COVID-19 reported by the World Health Organization and the implementation date of non-pharmaceutical interventions (NPIs) reported by the Oxford COVID-19 Government Response Tracker.
In each of the seven included countries, the average IPP was lower in 2020 than in 2010-2019 (P < 0.01), with the largest difference being 31.1% (95% confidence interval 28.4-33.7%). In Argentina, Bolivia, Chile and South Africa, higher IPPs were observed during epidemiological weeks 4-16 in 2020 compared with the same weeks in 2010-2019. The IPP increased after NPIs were implemented in Argentina and South Africa, but started to decline in Bolivia, Chile, Madagascar and Paraguay before NPI implementation.
Influenza burden and activity decreased in 2020 in the Southern hemisphere. The temporal decline in influenza activity varied between countries.
虽然 2020 年北半球流感病例有所减少已被广泛报道，但南半球流感传播动态仍不明确。
本研究分析了南半球国家中流感阳性比例（IPP）在 2010-2019 年和 2020 年之间的变化，这些国家的 FluNet 数据中 IPP 的缺失率≤40%，以评估 2019 年冠状病毒病（COVID-19）与流感活动之间的关系。分析考虑了世界卫生组织报告的 COVID-19 发病率和牛津 COVID-19 政府反应追踪器报告的非药物干预（NPI）实施日期。
在纳入的七个国家中，2020 年的平均 IPP 均低于 2010-2019 年（P < 0.01），最大差异为 31.1%（95%置信区间 28.4-33.7%）。在阿根廷、玻利维亚、智利和南非，2020 年的流行病学第 4-16 周 IPP 高于 2010-2019 年同期。在阿根廷和南非实施 NPI 后，IPP 增加，但在玻利维亚、智利、马达加斯加和巴拉圭实施 NPI 之前，IPP 开始下降。
2020 年南半球流感负担和活动减少。流感活动的时间下降在各国之间有所不同。
