Clinical trial Recruiting at 7 sites Observational Ages 18 and up

Observational study of healthcare workers' immunity to COVID-19

Official title: Health Care Workers Cohort Study in the EuCARE Project (EuCARE-HCW)

Run by Euresist Network GEIE · NCT05534009 · Data updated 2026-11-12

This study looks at how long and how well healthcare workers' immunity to COVID-19 lasts after vaccination or infection, while also checking if new virus variants can dodge that immunity.

More COVID-19 trials

Quick facts

Study typeObservational
Ages18 Years and up
SexAll
Enrollment1800 (estimated)
SponsorEuresist Network GEIE
Academic / other
Locations7 sites (Düsseldorf and 6 other locations)
StatusRecruiting
StartedApril 1, 2022
Main results expectedDecember 15, 2025
Study endsDecember 15, 2025
Registry record updatedSeptember 19, 2025
Trial IDNCT05534009 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates for this study are adult healthcare workers over 18 years old with documented vaccination or SARS-CoV-2 infection status.

Probably not a fit

Patients who do not work in healthcare or do not have a history of vaccination or SARS-CoV-2 infection may not benefit from this study.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

The EuCARE-HCW study is an observational multicentre project that collects both retrospective and prospective data from healthcare workers who have either been vaccinated against COVID-19 or have had a confirmed SARS-CoV-2 infection. Participants will provide biological samples periodically over 12-24 months to analyze the impact of different viral variants on immunity. The study aims to understand the duration and breadth of immunity following vaccination and natural infection, as well as the potential for vaccine escape by various SARS-CoV-2 variants. This research involves collaboration across eight countries, enhancing the diversity of data collected.

Why it matters

Potential benefit: If successful, this study could provide valuable insights into the effectiveness of COVID-19 vaccines and natural immunity, potentially guiding future vaccination strategies.

How similar studies have gone: Other studies have shown success in analyzing immunity to COVID-19 variants, making this approach both relevant and necessary.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

The study subjects will be selected based on the following inclusion criteria:

1. Adult (\>18 years) HCW with mandatory information on their SARS-CoV-2 infection and vaccination status.
2. For those with a history of SARS-CoV-2 infection, diagnosis obtained by detection of SARS-CoV-2 RNA
3. Having a signed informed consent when required by ethical approval

Exclusion Criteria: NONE

Where it's running

  • Heinrich Heine university
    Düsseldorf, Germany
    Recruiting
  • Azienda Socio-Sanitaria Territoriale Santi Paolo e Carlo
    Milan, Italy
    Recruiting
  • Ieo Istituto Europeo Di Oncologia
    Milan, Italy
    Recruiting
  • Viesoji Istaiga Vilniaus Uiversiteto Ligoninė Santaros klinikos
    Vilnius, Lithuania
    Recruiting
  • Hospital Juan Ghaham Casasus
    Villahermosa, Mexico
    Recruiting
  • Centro Hospitalar de Lisboa Ocidental
    Lisbon, Portugal
    Recruiting
Show 1 more location
  • Bach Mai Hospital
    Hanoi, Vietnam
    Recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.