Aix-Marseille Univ, CNRS, Institut Neurosciences Timone, Marseille, France.
Aix-Marseille Univ, CNRS, Aix-Marseille School of Economics, Marseille, France.
PLoS One. 2023 Feb 27;18(2):e0281943. doi: 10.1371/journal.pone.0281943. eCollection 2023.
We provide a novel way to correct the effective reproduction number for the time-varying amount of tests, using the acceleration index (Baunez et al., 2021) as a simple measure of viral spread dynamics. Not correcting results in the reproduction number being a biased estimate of viral acceleration and we provide a formal decomposition of the resulting bias, involving the useful notions of test and infectivity intensities. When applied to French data for the COVID-19 pandemic (May 13, 2020-October 26, 2022), our decomposition shows that the reproduction number, when considered alone, characteristically underestimates the resurgence of the pandemic, compared to the acceleration index which accounts for the time-varying volume of tests. Because the acceleration index aggregates all relevant information and captures in real time the sizable time variation featured by viral circulation, it is a more parsimonious indicator to track the dynamics of an infectious disease outbreak in real time, compared to the equivalent alternative which would combine the reproduction number with the test and infectivity intensities.
我们提供了一种新的方法来校正随时间变化的检测量的有效繁殖数，使用加速指数（Baunez 等人，2021）作为病毒传播动力学的简单衡量标准。不进行校正会导致繁殖数成为病毒加速的有偏差估计，我们提供了对由此产生的偏差的正式分解，涉及测试和传染性强度的有用概念。当应用于 COVID-19 大流行的法国数据（2020 年 5 月 13 日-2022 年 10 月 26 日）时，我们的分解表明，仅考虑繁殖数会导致对大流行反弹的低估，而加速指数则考虑了随时间变化的检测量。由于加速指数综合了所有相关信息，并实时捕捉到病毒传播的显著时间变化，因此与将繁殖数与测试和传染性强度相结合的等效替代方法相比，它是实时跟踪传染病爆发动态的更简约指标。
