Dynamics of non-household contacts during the COVID-19 pandemic in 2020 and 2021 in the Netherlands

Abstract

The COVID-19 pandemic was in 2020 and 2021 for a large part mitigated by reducing contacts in the general population. To monitor how these contacts changed over the course of the pandemic in the Netherlands, a longitudinal survey was conducted where participants reported on their at-risk contacts every two weeks, as part of the European CoMix survey. The survey included 1659 participants from April to August 2020 and 2514 participants from December 2020 to September 2021.We categorized the number of unique contacted persons excluding household members, reported per participant per day into six activity levels, defined as 0, 1, 2, 3-4, 5-9 and 10 or more reported contacts. After correcting for age, vaccination status, risk status for severe outcome of infection, and frequency of participation, activity levels increased over time, coinciding with relaxation of COVID-19 control measures.

Nationwide SARS-CoV-2 Seroprevalence Trends in the Netherlands in the Variant of Concern Era, 2021-2022: an Ongoing Prospective Cohort Study

“…Moreover, in-depth questionnaire data allowed investigation into (sub)groups. Response rates in children were rather low and drop-out rates high, however since children were less restricted by control measures and schools were mostly open, we do not expect large differences between children in terms of exposure, and this was also confirmed by contact data [34, 35]. Despite random selection and weighting our sample, some groups are underrepresented, such as those living in nursing homes – that were hit hard pre-Alpha – and non-Western, who might have refrained from participation due to digital- and/or language barriers.…”

Projecting COVID-19 intensive care admissions in the Netherlands for policy advice: February 2020 to January 2021

“…By uniformly sampling from the uncertainty ranges of the Fermi estimates, 200 contact matrices were obtained to describe the effect of a given set of COVID-19 control measures. On 28 May 2020, new estimates were made for all sets of control measures, to match the observations of the first CoMix contact study (19, 20), and new matrices were created.…”

“…In 2020 an international collaboration started collecting contact survey data in several European countries (19). We used the data of the first survey conducted in the Netherlands in early April 2020 (20).…”

Quality of place as the winner of the third wave of the COVID-19 pandemic in terms of quality of life. Will this knowledge strengthen the development of geographical psychology?

“…The respiratory disease SARS affected Canada, Spain, Russia, Brazil, India and Australia, while the respiratory disease MERS affected North African countries, Turkey, Iran and Saudi Arabia a few years after SARS. Both SARS and MERS had effects on countries in Western Europe, the USA and China [ [1] , [2] , [3] , [4] , [5] , [6] ]. There are several reasons for the greater spread of these diseases compared to the Spanish flu, one of which can be considered the phenomenon of mass air travel, which has fully manifested in the most recent pandemic.…”