The effect of #NPIs on #influenza throughout the #COVID19 #pandemic: an 8-year interrupted time series study
Abstract Limited information is available on the impact of non-pharmaceutical interventions (NPIs) and immune debt on influenza during COVID-19 . This retrospective population-based research examined the effect of the COVID-19 pandemic on the prevalence of influenza-like illness (ILI) cases and influenza positive cases in Sichuan Province . Interrupted time series analysis (ITS) was conducted using data gathered from surveillance hospitals throughout 21 cities , including information on patients diagnosed with ILI and positive nucleic acid testing. Subsequent to the implementation of NPIs, there was a notable temporary reduction in both the incidence of ILI cases and confirmed influenza cases, decreasing by 94.7% and 98.0%, respectively (P<0.001). The weekly trend in influenza-positive cases was notable (+4.1%/week, P=0.001). Following the execution of the second-phase intervention, the fluctuations in the transient changes of ILI patients and influenza-positive cases varied ;...