Basel
Increase in seroprevalence
In the canton of Basel-Landschaft, 11% of those tested had antibodies to SARS-CoV-2 from November 2020 to mid-February 2021, and in the canton of Basel-Stadt, the figure was 17%. For both cantons combined, the seroprevalence was 13%. Last fall, this was still 6%. The values have thus increased substantially in the second Corona wave. Looking at the group of people over 75 years of age who have been tested since mid-January, a slight effect of the vaccinations is already visible. However, the number of people tested in this group was small over this short period of time. The COVCO-Basel digital study examines in greater depth the impact of the pandemic and the Federal Council's measures on the population. Soon, 60,000 people will be invited to participate in monthly questionnaires on topics such as working conditions, homeschooling, living environment, social environment and mental health during the pandemic. For more information, visit the website.
Bern
Recruitment by bus and in hospital
In early March, the canton of Bern officially recruited its 400 participants for phase 3 of the study. Thanks to recruitment at Inselspital and through the CoronaImmunitas bus, a representative estimate for the total population can be derived. The first results of the 3rd phase show that only 14% of adult Bernese have been infected with the coronavirus and have developed antibodies. The Bern team is already ready for Phase IV, which will start around June.
Eastern Switzerland
Target values achieved
The recruitment of adults in St. Gallen and Graubünden has been completed. The target of 300 participants per canton was reached. The targeted number of household contacts was also achieved.
Children and adolescents can still register until the end of March. Blood samples are still being taken at isolated test centers.
Fribourg
Second report to follow shortly
Nearly 700 people have volunteered to participate in our study and with their help the third phase of Corona Immunitas in Freiburg is now complete. The proportion of people with SARS-CoV-2 antibodies in their blood has increased from 8% (October 2020) to 19% (December 2020). A report with more information will be published soon. In the meantime, please find here the first report from Corona Immunitas Freiburg.
Nestlé
Analysis of seroprevalence underway
The first test phase within the Nestlé Group ended on February 11 and involved 424 participants at the two participating study sites: Nestlé Research in Vers-chez-les-Blanc and the Nespresso factory in Romont. Seroprevalence analyses are currently ongoing.
Geneva
Young persons between 18 and 35 years of age have highest seroprevalence
In Geneva, the third phase of the study ended in December 2020. It was conducted among 4,000 people and shows the following results:
- More than one-fifth of Geneva residents (21%) have developed antibodies to SARS-CoV-2.
- The least exposed were young children (0-6 years) and people over 65 years with lower than average seroprevalence: 15% for children under 6 years, 15% for adults aged 65-74 years, and 9% for people over 75 years.
- Young people between 18 and 35 years of age were most affected. More than a quarter of them developed antibodies against SARS-CoV-2: 25% in the 18-25 age group and 26% in the 25-35 age group.
- The other age categories are close to the average (21%).
The study will continue via the Specchio-COVID19 platform, and a new phase of testing is expected to begin in spring 2021.
Lausanne
A quarter of Vaudois are now immune to coronavirus, regardless of age.
Between February 1 and 6, blood was drawn from 1,081 participants in the Seroco-ViD study. After their analysis, preliminary results were published: 25% of the Vaud population currently has antibodies to coronavirus, regardless of age. Although the virus still circulates most frequently in adults between 20 and 40 years of age, immunity has increased in all age groups, including the elderly: 1/5 of people between 65 and 75 years of age and almost 1/3 of people over 75 years of age (without EMS) are protected, partly by vaccination. More information (in French) here.
Lucerne
First Vaccination Effects Detectable
Phase 3 of Corona Immunitas has now been completed. In the canton of Lucerne, more than 400 study participants were tested for coronavirus antibodies. Now 100% of the test results are available. Antibodies against the coronavirus were detected in about 18 percent of the participants in the canton of Lucerne (seroprevalence). This rather high percentage, compared to Switzerland, could also be achieved because vaccinations were started early in the canton of Lucerne. In general, it can be said that one fifth of the population of the canton of Lucerne already has antibodies against the coronavirus. Detailed information about the region can be found here.
Neuchâtel
Last blood draws take place
The third phase of Corona Immunitas ends in Neuchâtel. Two times 200 blood samples have been analyzed so far and the results will be communicated to the participants. They indicate a seroprevalence of currently 17.3%. Although this number is preliminary, it represents a strong increase over the 4.9% immunity rate observed in the fall of 2020. The final blood samples are currently being collected and the last 150 samples will be sent to the laboratory for analysis shortly.
Ticino
Second phase of serological testing
From November 2020 to early January 2021, Corona Immunitas Ticino started the second testing phase of the serological assays. To respond to the second wave of the SARS-CoV-2 virus epidemic, USI and SUPSI, in collaboration with the IRB, EOP and the Applied Microbiology Laboratory, have expanded the test sample compared to the first phase, including more children, adolescents and elderly (over 65 years).
The results
Thanks to a dense network of collaborationsin the area, 1,463 serological tests were performed. Seroprevalence against the SARS-CoV-2 virus was 6% in persons older than 75 years, 7% in persons aged 65-74 years, 12% in children aged 5-12 years, and 18% in adolescents aged 13-19 years. Across all age groups, seroprevalence showed a 16% increase from the first testing phase in July 2020 (prevalence of 11.7% in adults aged 20-64 years).
The study continues
More than ever, it is important to continue to complete the weekly and monthly questionnaires to monitor the progress of the epidemic in our canton. It is important not only to understand how symptoms, behaviors and perceptions will change during and after the vaccination campaign, but also to measure the impact of these changes on the health and well-being of the Ticino population.
Winterthur
Data analyses in progress
Winterthur has started the data analyses. The final sample, drawn randomly from vocational schools, high schools and the university in Winterthur, includes data from 273 women and 146 men with an average age of 20. The period between September 28 and December 17, 2020 is considered. The analyses will provide insights into how many adolescents and young adults have already formed antibodies and whether there are differences between genders and school types. These and other results are expected in the coming months. Currently, preparations are underway for the 2nd data collection, which is expected to start at the end of April due to the epidemiological situation.
Zurich
End of 3rd test phase - start of vaccination study
The third phase of Corona Immunitas Zurich was completed. Seroprevalence across all age groups is 11% percent by the end of January. A further sub-study was also conducted with around 300 employees of the Center for Dental Medicine at the University of Zurich. For the Ciao Corona school study, the third test phase will begin in mid-March and an article on the first and second test phases has just been published in the British Medical Journal. The Zurich Coronavirus Cohort Study has published initial results and is currently working to analyze more data. In March, a new study, the Zurich Coronavirus Vaccination Study, started. The aim of this study is to investigate the immune response to the vaccines approved in Switzerland in randomly selected and therefore representative samples of individuals.
