NCT04448717: CiaoCorona

COVID-19: Longitudinal Study of Seroprevalence of SARS-CoV-2 Antibodies and Development of Immunity in School Children

Completed Last updated 3 April 2025

What this trial tests

trial testing COVID-19 Antibody testing in SARS-CoV 2 in 4,250 participants. Completed in 20 July 2022.

Timeline

16 June 2020

Primary endpoint
20 July 2022

20 July 2022

Quick facts

Lead sponsor	University of Zurich
Status	Completed
Study type	OBSERVATIONAL
Enrollment	4,250
Start date	16 June 2020
Primary completion	20 July 2022
Estimated completion	20 July 2022
Sites	1 location across Switzerland

Drugs / interventions tested

• COVID-19 Antibody testing

Conditions studied

• SARS-CoV 2 — all drugs for SARS-CoV 2 →
• COVID-19 — all drugs for COVID-19 →

Sponsor

University of Zurich

Who can join

5 and older, any sex, with SARS-CoV 2 or COVID-19. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

There is a lack of knowledge about how many children are infected with SARS-CoV-2, how often they are asymptomatic, and how long the immunity persists.

The main purpose of this study is to measure antibodies to SARS-CoV-2, symptoms, and risk factors in a representative cohort of children and adolescents in the canton of Zurich, Switzerland, shortly after re-opening of the school system and thereafter. The study also investigates antibodies to SARS-CoV-2 in parents of the children and school personnel.

Publications & conference data

8 peer-reviewed publications reference this trial (live from Europe PMC):

1. Clustering and longitudinal change in SARS-CoV-2 seroprevalence in school children in the canton of Zurich, Switzerland: prospective cohort study of 55 schools.
   Ulyte A, Radtke T, Abela IA, Haile SR, et al · · 2021 · cited 59× · PMID 33731327 · DOI 10.1136/bmj.n616
2. Surveillance of Acute SARS-CoV-2 Infections in School Children and Point-Prevalence During a Time of High Community Transmission in Switzerland.
   Kriemler S, Ulyte A, Ammann P, Peralta GP, et al · · 2021 · cited 30× · PMID 33796490 · DOI 10.3389/fped.2021.645577
3. Seroprevalence and immunity of SARS-CoV-2 infection in children and adolescents in schools in Switzerland: design for a longitudinal, school-based prospective cohort study.
   Ulyte A, Radtke T, Abela IA, Haile SR, et al · · 2020 · cited 28× · PMID 33063141 · DOI 10.1007/s00038-020-01495-z
4. Variation in SARS-CoV-2 seroprevalence across districts, schools and classes: baseline measurements from a cohort of primary and secondary school children in Switzerland.
   Ulyte A, Radtke T, Abela IA, Haile SR, et al · · 2021 · cited 22× · PMID 34312201 · DOI 10.1136/bmjopen-2020-047483
5. Cross-protective HCoV immunity reduces symptom development during SARS-CoV-2 infection.
   Abela IA, Schwarzmüller M, Ulyte A, Radtke T, et al · · 2024 · cited 9× · PMID 38270455 · DOI 10.1128/mbio.02722-23
6. Health-Related Quality of Life and Adherence to Physical Activity and Screen Time Recommendations in Schoolchildren: Longitudinal Cohort Ciao Corona.
   Haile SR, Gunz S, Peralta GP, Ulytė A, et al · · 2023 · cited 8× · PMID 37538234 · DOI 10.3389/ijph.2023.1606033
7. Determinants of health-related quality of life in healthy children and adolescents during the COVID-19 pandemic: Results from a prospective longitudinal cohort study.
   Haile SR, Peralta GP, Raineri A, Rueegg S, et al · · 2024 · cited 5× · PMID 38411717 · DOI 10.1007/s00431-024-05459-w
8. Persistent humoral immune response in youth throughout the COVID-19 pandemic: prospective school-based cohort study.
   Raineri A, Radtke T, Rueegg S, Haile SR, et al · · 2023 · cited 5× · PMID 38012137 · DOI 10.1038/s41467-023-43330-y