Systemdynamische Tipping-Point-Analyse epidemiologischer Zeitreihen im Abwasser
Systemdynamische Tipping-Point-Analyse epidemiologischer Zeitreihen im Abwasser
ABSTRACT
Abstract: In this paper, we investigate the detection of critical phase transitions (tipping points) in biological-epidemiological systems using passive, unbiased wastewater measurements from the ARA Werdhölzli wastewater treatment plant (autumn 2020). Traditional individual testing data suffer from severe selection and testing capacity biases (ascertainment bias). We demonstrate that the wastewater viral load (SARS-N1/N2) provides an ideal, aggregated signal to determine the exact turning point of outbreak dynamics using derivative analysis and system dynamics modelling. In late October 2020, the system tipped from linear to highly exponential growth at a measured concentration of C = 39.2 ng/L (normed gene copies). We calculate the cumulative prevalence at this tipping point to be precisely 0.43% of the total population in the catchment area (~2,050 cumulative cases out of 470,000 inhabitants), corresponding to an effective reproduction number of Reff ≈ 1.8 to 2.2. Finall
Abstract: In this paper, we investigate the detection of critical phase transitions (tipping points) in biological-epidemiological systems using passive, unbiased wastewater measurements from the ARA Werdhölzli wastewater treatment plant (autumn 2020). Traditional individual testing data suffer from severe selection and testing capacity biases (ascertainment bias). We demonstrate that the wastewater viral load (SARS-N1/N2) provides an ideal, aggregated signal to determine the exact turning point of outbreak dynamics using derivative analysis and system dynamics modelling. In late October 2020, the system tipped from linear to highly exponential growth at a measured concentration of C = 39.2 ng/L (normed gene copies). We calculate the cumulative prevalence at this tipping point to be precisely 0.43% of the total population in the catchment area (~2,050 cumulative cases out of 470,000 inhabitants), corresponding to an effective reproduction number of Reff ≈ 1.8 to 2.2. Finall