Development of the reproduction number from coronavirus SARS-CoV-2 case data in Germany and implications for political measures

BMC Medicine

Berit Lange¹  Patrizio Vanella²  Arnab Bandyopadhyay³  Sahamoddin Khailaie³  Pietro Mascheroni³  Marta Schips³  Sebastian C. Binder³  Tanmay Mitra³  Michael Meyer-Hermann⁴ 

[1] Department of Epidemiology, Helmholtz Centre for Infection Research (HZI), Inhoffenstr. 7, 38124, Braunschweig, Germany;German Center for Infection Research (DZIF), Inhoffenstraße 7, 38124, Braunschweig, Germany;Department of Epidemiology, Helmholtz Centre for Infection Research (HZI), Inhoffenstr. 7, 38124, Braunschweig, Germany;Hannover Biomedical Research School (HBRS), Carl-Neuberg-Str. 1, 30625, Hannover, Germany;Chair of Empirical Methods in Social Science and Demography, University of Rostock, Ulmenstr. 69, 18057, Rostock, Germany;Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology (BRICS), Helmholtz Centre for Infection Research, Rebenring 56, 38106, Braunschweig, Germany;Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology (BRICS), Helmholtz Centre for Infection Research, Rebenring 56, 38106, Braunschweig, Germany;Institute for Biochemistry, Biotechnology and Bioinformatics, Technische Universität Braunschweig, Braunschweig, Germany;Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany;

关键词: SARS-CoV-2;    COVID-19;    Epidemiology;    Modeling;    Non-pharmaceutical interventions;    Reproduction number;    Healthcare usage;   

DOI  :  10.1186/s12916-020-01884-4

来源: Springer

【 摘 要 】

BackgroundSARS-CoV-2 has induced a worldwide pandemic and subsequent non-pharmaceutical interventions (NPIs) to control the spread of the virus. As in many countries, the SARS-CoV-2 pandemic in Germany has led to a consecutive roll-out of different NPIs. As these NPIs have (largely unknown) adverse effects, targeting them precisely and monitoring their effectiveness are essential. We developed a compartmental infection dynamics model with specific features of SARS-CoV-2 that allows daily estimation of a time-varying reproduction number and published this information openly since the beginning of April 2020. Here, we present the transmission dynamics in Germany over time to understand the effect of NPIs and allow adaptive forecasts of the epidemic progression.MethodsWe used a data-driven estimation of the evolution of the reproduction number for viral spreading in Germany as well as in all its federal states using our model. Using parameter estimates from literature and, alternatively, with parameters derived from a fit to the initial phase of COVID-19 spread in different regions of Italy, the model was optimized to fit data from the Robert Koch Institute.ResultsThe time-varying reproduction number (Rt) in Germany decreased to <1 in early April 2020, 2–3 weeks after the implementation of NPIs. Partial release of NPIs both nationally and on federal state level correlated with moderate increases in Rt until August 2020. Implications of state-specific Rt on other states and on national level are characterized. Retrospective evaluation of the model shows excellent agreement with the data and usage of inpatient facilities well within the healthcare limit. While short-term predictions may work for a few weeks, long-term projections are complicated by unpredictable structural changes.ConclusionsThe estimated fraction of immunized population by August 2020 warns of a renewed outbreak upon release of measures. A low detection rate prolongs the delay reaching a low case incidence number upon release, showing the importance of an effective testing-quarantine strategy. We show that real-time monitoring of transmission dynamics is important to evaluate the extent of the outbreak, short-term projections for the burden on the healthcare system, and their response to policy changes.

【 授权许可】

CC BY