Screening for COVID-19 and Monitoring of Serological Responses to SARS-CoV-2 in Healthcare Workers (SeCo)

Screening for SARS-CoV-2-Infections and Monitoring of Serological Responses to SARS-CoV-2 in Healthcare Workers

The main objectives of this study are 1) to establish the prevalence of SARS-CoV-2 in asymptomatic healthcare workers (HCWs) in an early phase of community spread as well as 2) to monitor the future spread of the disease by assessing serological responses to SARS-CoV-2 in symptomatic and asymptomatic HCWs over time and 3) to improve the assessment of the immune response and its protective effect as well as the assessment of infectivity of affected HCWs and 4) to evaluate the value and significance of antibody formation and serological antibody tests and 5) to be able to evaluate possible future preventive and / or therapeutic approaches against SARS-CoV-2, e.g. to assess vaccination effects

Study Overview

• Status: Completed
• Conditions: SARS-CoV-2
• Intervention / Treatment: Diagnostic test: Nasal swab; Diagnostic test: Serum testing

Detailed Description

This study aims to collect information on staff working at the Greifswald University hospital.

Over a 5 year period, a maximum of 12 study visits per participant are planned. At each visit, nasal/throat swabs (for PCR testing) and/or blood samples (to assess immunological responses, e.g. for SARS-CoV-2 antibody testing) will be collected. This will help to gain a better understanding of viral load and immunological responses, e.g. antibody development and their effects over time.

At study visit 2 - 12, participants will also be asked to fill in a questionnaire (asking for SARS-CoV-2 risk factors, perceived risk, impact of the pandemic on their quality of life, their interest in getting a SARS-CoV-2 vaccine/their SARS-CoV-2 vaccination status and vaccination side effects).

The remaining blood samples will be stored in a repository for future research.

The study is part of a modular SARS-CoV-2-research programme of the University Medicine Greifswald.

• Study Type: Observational
• Enrollment (Actual): 1092

Contacts and Locations

Study Locations

• Germany
  • Greifswald, Germany
    • Greifswald University Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Health Care Worker

Description

Inclusion Criteria:

1. >= 18 years of age
2. Willing and able to complete a written consent form
3. Willing to have blood samples stored for future research
4. Healthcare worker employed at Greifswald University Hospital

Exclusion Criteria:

1. < 18 years of age
2. Decline to participate

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
(1) Healthcare workers; All healthcare workers at University Medicine Greifswald who were enrolled in the study between 04/2020-08/2020	Diagnostic test: Nasal swab; SARS-CoV-2 PCR; Diagnostic test: Serum testing; Anti-SARS-CoV2 S protein IgG ELISA, serological changes after SARS-CoV-2 vaccination
(2) Healthcare workers in high-risk areas of the hospital (intensive care, emergency medicine); Healthcare workers at University Medicine Greifswald who were enrolled in the study between 01/2021-03/2021	Diagnostic test: Nasal swab; SARS-CoV-2 PCR; Diagnostic test: Serum testing; Anti-SARS-CoV2 S protein IgG ELISA, serological changes after SARS-CoV-2 vaccination
(3) Healthcare workers after SARS-CoV-2 vaccination; Healthcare workers at University Medicine Greifswald who received a SARS-CoV-2 vaccination within the last 7-21 days	Diagnostic test: Nasal swab; SARS-CoV-2 PCR; Diagnostic test: Serum testing; Anti-SARS-CoV2 S protein IgG ELISA, serological changes after SARS-CoV-2 vaccination

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of people with detectable antibodies to SARS-CoV-2	Anti-SARS-CoV-2 S protein IgG ELISA/ Anti-SARS-CoV-2 NCP IgG ELISA	1 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of people with detectable SARS-CoV-2 nucleic acid	SARS-CoV-2 PCR	First study visit (baseline)

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of people with detectable antibodies to SARS-CoV-2	Anti-SARS-CoV-2 S protein IgG ELISA/ Anti-SARS-CoV-2 NCP IgG ELISA	First study visit (baseline)
Number of people with detectable antibodies to SARS-CoV-2	Anti-SARS-CoV-2 S protein IgG ELISA/ Anti-SARS-CoV-2 NCP IgG ELISA	2 years
Number of people with detectable antibodies to SARS-CoV-2	Anti-SARS-CoV-2 S protein IgG ELISA/ Anti-SARS-CoV-2 NCP IgG ELISA	3 years
Number of people with detectable antibodies to SARS-CoV-2	Anti-SARS-CoV-2 S protein IgG ELISA/ Anti-SARS-CoV-2 NCP IgG ELISA	4 years
Number of people with detectable antibodies to SARS-CoV-2	Anti-SARS-CoV-2 S protein IgG ELISA/ Anti-SARS-CoV-2 NCP IgG ELISA	5 years
Number of people with detectable SARS-CoV-2 nucleic acid	SARS-CoV-2 PCR	2 years
Number of people with detectable SARS-CoV-2 nucleic acid	SARS-CoV-2 PCR	3 years
Number of people with detectable SARS-CoV-2 nucleic acid	SARS-CoV-2 PCR	4 years
Number of people with detectable SARS-CoV-2 nucleic acid	SARS-CoV-2 PCR	5 years
SARS-CoV-2 risk factors, perceived risk of infection, impact of the pandemic on quality of life, vaccination interest/vaccination status, vaccination side effects	As assessed by a questionnaire	1 year
SARS-CoV-2 risk factors, perceived risk of infection, impact of the pandemic on quality of life, vaccination interest/vaccination status, vaccination side effects	As assessed by a questionnaire	2 years
SARS-CoV-2 risk factors, perceived risk of infection, impact of the pandemic on quality of life, vaccination interest/vaccination status, vaccination side effects	As assessed by a questionnaire	3 years
SARS-CoV-2 risk factors, perceived risk of infection, impact of the pandemic on quality of life, vaccination interest/vaccination status, vaccination side effects	As assessed by a questionnaire	4 years
SARS-CoV-2 risk factors, perceived risk of infection, impact of the pandemic on quality of life, vaccination interest/vaccination status, vaccination side effects	As assessed by a questionnaire	5 years
Serological changes after SARS-CoV-2 vaccination	Serological changes after SARS-CoV-2 vaccination, cohort 3 only	7 days to 6 months after vaccination

Collaborators and Investigators

• Sponsor: University Medicine Greifswald
• Collaborators: Friedrich Loefler Institute for Animal Health; EUROIMMUN AG
• Investigators: Principal Investigator: Nils-Olaf Hübner, Prof.Dr., University Medicine Greifswald; Principal Investigator: Karsten Becker, Prof.Dr., University Medicine Greifswald

Publications and helpful links

General Publications

• Handtke S, Wolff M, Zaninetti C, Wesche J, Schonborn L, Aurich K, Ulm L, Hubner NO, Becker K, Thiele T, Greinacher A. A flow cytometric assay to detect platelet-activating antibodies in VITT after ChAdOx1 nCov-19 vaccination. Blood. 2021 Jul 1;137(26):3656-3659. doi: 10.1182/blood.2021012064.
• Esefeld M, Handtke S, Kaiser R, Nicolai L, Di Fina L, Rossaro D, Wesche J, Rath J, Wienrich AC, Hoffmann T, Harasser L, Feistritzer C, Loacker L, Lotfi K, Holmstrom M, Antovic J, Steil L, Volker U, Ulm L, Becker K, Hubner NO, Greinacher A, Thiele T. Platelet-activating histone/antihistone IgG complexes in anti-PF4-negative thrombosis and thrombocytopenia syndrome. Blood Adv. 2025 Aug 26;9(16):4323-4335. doi: 10.1182/bloodadvances.2024015076.

Study record dates

Study Major Dates

• Study Start (Actual): April 27, 2020
• Primary Completion (Actual): April 23, 2021
• Study Completion (Actual): April 27, 2025

Study Registration Dates

• First Submitted: April 29, 2020
• First Submitted That Met QC Criteria: April 29, 2020
• First Posted (Actual): April 30, 2020

Study Record Updates

• Last Update Posted (Actual): November 20, 2025
• Last Update Submitted That Met QC Criteria: November 17, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: epidemiology; immunity; Serology; antibody formation
• Other Study ID Numbers: BB 068/20

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No