Coronavirus: Monitoring

Here you will find reports on the monitoring of COVID-19 and related topics. Monitoring is designed to provide further information of relevance to the progression of the pandemic in addition to the epidemiological data.

Analysing and monitoring wastewater

Research project: Analysing wastewater for the presence of Sars-CoV-2

People who are infected with the Sars-CoV-2 virus excrete genetic material (RNA) of the virus in their stool. This way RNA gets into the wastewater, where it can be detected. Since February 2021 the Swiss Federal Institute of Aquatic Science and Technology (Eawag) has been gathering samples of wastewater from six treatment plants on a daily basis and analysing them for Sars-CoV-2. These tests can help determine whether and to what extent people in the catchment area of the treatment plant are infected.

Until the end of July 2021 the treatment plants tested were in Lausanne, Laupen, Zurich, Lugano, Altenrhein and Chur. They were chosen on the basis of both their geographic distribution and the structure of their catchment areas – in other words whether they are urban or rural. Since August 2021 the Geneva wastewater treatment plant has been sampled instead of the Lausanne plant because i) its catchment area is larger, ii) an international airport is located in the catchment area, and iii) there is a substantial flow of cross-border commuters.

The data from these wastewater analyses are able to give a good depiction of the development of the pandemic in the various catchment areas. In the ideal case, wastewater analyses thus have the potential to detect hotspots and any renewed increases in case numbers early on. The studies of wastewater samples will run until spring 2023, with the final report also due to appear around this time.

You will find more information on the Eawag website. The FOPH is providing funding and expertise to support the project.

Monitoring wastewater: keeping track of the epidemiological situation

On the basis of the findings of the research project described above, a national monitoring system was established covering around 100 treatment plants. It will run until at least the end of 2022.
Monitoring wastewater is an efficient means of keeping track of the viral load and the variants circulating in the population. It provides rapid, broad-based, anonymous and reliable data, something that is particularly relevant when fewer and fewer COVID-19 tests are being conducted. Three to six times a week, treatment plants supply samples for analysis by designated cantonal and private laboratories. They cover around 70% of the population. In addition, daily wastewater samples from six selected treatment plants are sequenced, enabling the virus variants circulating to be promptly identified. The costs of these analyses are paid by the federal government.

The data gathered to track the epidemiological situation are evaluated on an ongoing basis and can be found on the dashboard. Further information is also available on the ETH webpage that covers the monitoring of wastewater.

Wastewater-based surveillance of SARS-CoV-2 in various countries

In this document you will find an overview of how a selection of countries are monitoring the spread of SARS-CoV-2 by analysing wastewater.

Corona Immunitas

It is still important to investigate the population’s immunity to the coronavirus by analysing blood for the presence of antibodies (seroprevalence). This allows an evaluation of the percentage of the population that has immunity to the coronavirus as a result of infection, vaccination or both.

A nationwide long-term monitoring programme seeks to provide insights into the spread and impact of the coronavirus. It has been running since April 2020, and is being conducted as part of Corona Immunitas, a national science programme of the Swiss School of Public Health (SSPH+).

Objectives of the programme
The detection of antibodies is intended to:

  • provide evidence on the spread of the coronavirus in Switzerland’s various regions and in specific population and occupational groups;
  • provide information on whether and to what extent measures to combat the spread of the coronavirus are working;
  • determine whether a past infection protects from re-infection and if so, how long such protection lasts.

Regular surveys are also conducted to gain additional insights into the effects of SARS-CoV-2 infection (including the long-term effects) and vaccination.

Programme: participation, scope and duration
Fourteen universities and institutions from all over Switzerland are participating in Corona Immunitas. Over 40 studies are being conducted involving some 50,000 Swiss residents. In summer 2021 the decision was taken to no longer conduct research into immunity in the population at all sites. The development of seroprevalence over time is now examined at one site in each language region: Ticino, Vaud and Zurich.

Corona Immunitas will run until the end of August 2023.

The FOPH is contributing to the programme and providing financial support. The findings will provide an important basis to help federal and cantonal policymakers determine the next steps in combating the coronavirus epidemic.

Monitoring of COVID-19 in Swiss hospitals

Hospitalisations of patients with COVID-19 have been recorded in a hospital sentinel surveillance system (COVID-19 Hospital Based Surveillance CH-SUR) in addition to the mandatory reporting system since the beginning of the pandemic. The aim of such monitoring is to obtain detailed clinical and epidemiological information on the burden of disease, its clinical course (such as ICU treatment) and risk factors. CH-SUR is being jointly coordinated by the FOPH, the Institute of Global Health of the University of Geneva and the Infection Control Program of the Geneva University Hospitals (HUG). The project is financed by the FOPH. The hospital sentinel surveillance system has also been used to monitor hospitalisations of influenza patients since 2018.

The key results and findings of CH-SUR’s monitoring activities are published in a monthly report in English with summaries in French, German and Italian. Below you will find the latest such report, together with the reports previously published to date. Since November 2022 the report has also included assessments of the influenza hospitalisation situation during the flu season.

Latest edition


Implementation of the measures and the health and wellbeing of the population

The FOPH is observing how members of the public are putting the measures to contain the coronavirus into practice, and how these measures are affecting their health and lives, among other things via the following two projects:

Covid Norms
The Covid Norms project run by the University of Zurich (UZH) is examining, among other things, the preventive behaviour of the population in Switzerland. It shows how broadly measures are being implemented and to what extent they are being accepted by the public.

The project employs various survey tools, co-financed by the FOPH and in some cases drawing on its expertise, to find out about people’s attitudes towards protecting themselves from the coronavirus and their perceptions of the same. Its findings are published on the Covid Norms website.

COVID-19 Social Monitor
The COVID-19 Social Monitor run by the ZHAW Zurich University of Applied Sciences has been steadily gathering data since the beginning of the pandemic on:

  • people’s wellbeing
  • people’s physical and mental health
  • people’s health-related behaviours and
  • the employment situation within the Swiss population.

The FOPH is co-funding the project`s and providing expertise. For information on its findings, visit the ZHAW website.

Report on social tensions

The Sotomo research institute conducted ten online surveys on behalf of SRG between March 2020 and February 2022 to gauge the public mood. As SRG’s Corona Monitor shows, tackling the crisis triggered by the coronavirus pandemic led to social and private tensions.

To better understand and categorise this tense public mood, the FOPH commissioned Sotomo to conduct a further analysis of the survey data from SRG’s Corona Monitor. The aim of this special analysis was to cast light on the attitudes of various population groups to the political and the social management of the pandemic, and to gain well-founded insights therefrom.

Last modification 07.06.2023

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