A dataset of non-pharmaceutical interventions on SARS-CoV-2 in Europe

Abstract

During the second half of 2020, many European governments responded to the resurging transmission of SARS-CoV-2 with wide-ranging non-pharmaceutical interventions (NPIs). These efforts were often highly targeted at the regional level and included fine-grained NPIs. This paper describes a new dataset designed for the accurate recording of NPIs in Europe's second wave to allow precise modelling of NPI effectiveness. The dataset includes interventions from 114 regions in 7 European countries during the period from the 1st August 2020 to the 9th January 2021. The paper includes NPI definitions tailored to the second wave following an exploratory data collection. Each entry has been extensively validated by semi-independent double entry, comparison with existing datasets, and, when necessary, discussion with local epidemiologists. The dataset has considerable potential for use in disentangling the effectiveness of NPIs and comparing the impact of interventions across different phases of the pandemic.

Fig. 1

The effectiveness of interventions in Europe’s second wave as estimated by Sharma et al.. Percentage reductions in the reproduction number R shown, this is the instantaneous reproduction number Rt. Rt is the expected number of secondary infections arising from a primary infection at time t. Markers indicate posterior median estimates, lines indicate the 50% and 95% posterior credible intervals. A negative 1% reduction refers to a 1% increase in R (A) Effectiveness of the main interventions included in Sharma et al.. Intervention names preceded by “All” show the combined effect of multiple interventions. For example, “All gatherings banned” shows the combined effect of banning all public gatherings and all household mixing in private. (B) Individual effectiveness estimates for gathering types, separated into public gatherings and household mixing in private. Figure reproduced from Sharma et al..

Fig. 2

Overview of implementation of NPIs. The total number of days that each intervention was implemented, aggregated across regions but separated by country. The dashed vertical line indicates the total-number of region-days recorded in our dataset. Note that gathering and household mixing thresholds shown in this figure represent those used by Sharma et al., the dataset itself contains the precise limit on the number of attendants and households for each type of gathering. Figure reproduced from Sharma et al..

Fig. 3

Process of data collection; from exploration to validation.