Police COVID-19 Serosurvey

Study Overview
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Brief Summary
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The investigators aim to determine the immune status of the employees of the cantonal police of Bern against SARS-CoV-2 over a period of 1 year, and to investigate the risk profile of the study participants and their risk of SARS-CoV-2 exposure in their working and private environments, as well as to evaluate the use of personal protective equipment at potential exposure instances.

Detailed Description
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i) To determine the extent of infection with seroprevalence data in the special population of police officers of the canton Bern. ii) To determine risk factors for infection by comparing the proportion of seropositivity (infected versus noninfected individuals). The investigators hypothesize that police officers with fieldwork activity will have a higher seroprevalence than will office and administration personnel. The investigators hypothesize that working in the city of Bern will be associated with a higher seroprevalence than will working in other geographic areas of the canton (i.e. rural area). iii) To monitor COVID-19 antibody titres and neutralizing capacity over time and to associate them with reinfection rates and infection-free intervals in police officers after accidental contact with a proven COVID-19 case. The investigators hypothesize that in seropositive individuals, there will be a decreasing dynamic of antibody titres over the one-year study period, and hence, a decrease of neutralizing capacity.

Official Title
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Police Officer COVID-19 Seroprevalence Survey in the Canton of Bern, Switzerland

Conditions
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SARS-CoV-2 Infection, Volunteers, Healthy

Intervention / Treatment
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* Diagnostic Test: Blood sampling
* Other: Online Questionnaire


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Police officers of the cantonal police of Bern volunteering to participate in the study. Exclusion Criteria: Refusal or inability to give informed consent or contraindication to venepuncture.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: Blood sampling|Testing for the presence of SARS-CoV-2 antibodies|
|Other: Online Questionnaire|Questions on working place, risk profiles and PPE|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Seroprevalence | The variable of primary interest is COVID-19 seropositivity. This variable is measured at five time points over the one-year study period. The following baseline factors may have an influence on the primary endpoint and will be obtained: (i) pre-existing comorbidities, (ii) rural versus city distribution of working place, and (iii) office work versus field work. | One year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Risk profile assessment | The investigators will assess the proportion of symptomatic and asymptomatic cases among seropositive participants. The investigators will calculate the attack rate in different subgroup. These include (i) study participants with health-related risk factors (age>50 and age>60 years, diabetes, arterial hypertension, cardiovascular disease, chronic pulmonary disease, immune-compromised status due to host diseases, medical treatment, cancer, obesity), (ii) activity-related subgroups (i.e. fieldwork vs office activity), (iii) geography-related subgroups (i.e. city vs rural areas). In follow-up visits, the antibody titers (i.e. dynamic) and the neutralization capacity will be assessed. Thereby, the investigators will determine the change in serum levels of SARS-CoV-2 antibodies over time in seropositive participants. | One year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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COVID-19, SARS-COV-2, Antibodies, Seroprevalence