Evolution of Protective Immunization Against COVID-19 Among Hospital Workers in Health Care Facilities

Assistance Publique Hopitaux De Marseille1,000 enrolled

Overview

To measure the immunization rate (seroneutralization) in a population of exposed hospital workers (nursing staff assigned to dedicated COVID-19 care units, laboratory staff handling COVID-19 samples).

Current studies on seroconversion and the time course of immunity following exposure to SARS-CoV-2 do not document: i) Seroconversion in populations in repeated and frequent contact with patients; ii) The temporal dynamics of seroconversion at medium term. These two elements are however fundamental in the comprehension and management of this epidemic or of its potential resurgence in the following months and years. Objective: To measure the immunization rate (seroneutralization) in a population of exposed hospital workers (nursing staff assigned to dedicated COVID-19 care units, laboratory staff handling COVID-19 samples). Secondary objectives: 1. Determine the kinetics of the protective response over 12 months (4 times). 2. Compare immunization profiles according to: gender, age, lockdown, blood type, occupational class, exposure, asymptomatic/symptomatic. 3. Compare immunization kinetics between exposed and low-exposure hospital workers. 4. To determine the characteristics of the ELISA test in comparison with the reference test (seroneutralization). Perspectives * To provide a reliable, affordable and faster serological test. * Understanding of the natural evolution of seroprotection in a population over time. * Sensitization to plasma donation for seropositive patients.

Study Type

INTERVENTIONAL

Allocation

NON_RANDOMIZED

Purpose

SCREENING

Masking

NONE

Enrollment

1,000

Conditions

Covid19

Interventions

Blood sampleOTHER

Seroneutralization and Elisa tests

Eligibility

Sex: ALLHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: Cohort of exposed hospital workers \- Hospital caregiver or non-clinician agreeing to participate in the study defined as: Healthcare personnel (physician, nurse, orderly, physical therapist, midwives) who have worked for a minimum of 2 weeks since March 1, 2020 in a care unit dedicated to the management of patients confirmed or suspected of COVID-19 infection, in the participating centers: intensive care units, emergency rooms, COVID-19 units; * Staff (physician, technician) who have worked for a minimum of 2 weeks since March 1, 2020 in the AP-HM laboratories handling samples from patients confirmed or suspected of having COVID-19 infection * Person affiliated to a social security system Cohort of 'unexposed' hospital workers * Hospital care worker (physician, nurse, orderly) willing to participate in the study who has not worked since March 1, 2020 in an intensive care unit or emergency department or other department dedicated to the management of patients confirmed or suspected of having COVID-19 infection. * Person affiliated with a social security system Exclusion Criteria: * Hospital worker declining to participate If the hospital worker changes assignment after the first collection, he/she remains in the exposed cohort. * Protected adult * Person under legal guardianship or curatorship

Locations (1)

Assistance Publique Des Hopitaux de Marseille

Marseille, France

RECRUITING

Outcomes

Primary Outcomes

To establish the level of immunization (seroprevalence) to COVID-19 as determined by the seroneutralization test in a population of exposed hospital workers

Positive seroneutralization test result: the threshold of positivity is set at 40, i.e. any serum with a seroneutralizing value greater than or equal to 40 will be considered positive.

Time frame: 4, 8 and 12 months follow-up visits after the initial visit

Secondary Outcomes

Kinetics of the protective antibody immune response (protective immunization against SARS-CoV-2 COVID-19) in a population of exposed hospital workers over a 12-month period.

The kinetics of "seroprevalence" will be defined by the results of the seroneutralization test at 4 time-points (4, 8 and 12 month follow-up visits after the initial visit).

Time frame: 4, 8 and 12 months follow-up visits after the initial visit

Compare immunization profiles

Combine multiple measurement in order to compare immunization profiles (symptomatic status,individual characteristics, i.e, gender, age range, condition of lockdown, blood type; professional characteristics and possible clinical signs.

Time frame: 12 months after the initial visit

Compare the seroprevalence of SARS-CoV-2 and the kinetics of immunization between two groups (exposed hospital workers and a less exposed hospital workers).

Compare between groups the results of the seroneutralization test over time.

Time frame: 4, 8 and 12 months follow-up visits after the initial visit

Identify the technical (sensitivity and specificity) and predictive (positive and negative predictive values) characteristics of the ELISA test evaluated in comparison with the reference test (serum neutralization) in the population of interest.

ELISA's test positivity will be defined with reference to the manufacturer's recommendations. For a ratio OD of the tested sample / kit control: * \<0.9: negative test * Between 0.9 and 1.1: unspecified test * \>1.1: positive test The result will be processed under two modalities: negative/indeterminate/positive and quantitative

Central Contacts

Laetitia Ninove, MCU-PH

CONTACT

+33 4 91 83 20 66 Laetitia.Ninove@ap-hm.fr

Data from ClinicalTrials.gov

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