Assessment of Incidence of SARS-CoV-2 Infection and COVID-19 in Brazil (AVISA)

Study Overview
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Brief Summary
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This is an observational study, meaning that no interventions is tested, to determine incidence of SARS-CoV-2 infection and COVID-19 in different clinical sites in Brazil in several age groups. The study aims to assess baseline number of infected participants and perform a follow-up along two years to determine the new cases occurring among participants during the period. All participants will collect blood samples to get more details on the immune response.

Detailed Description
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This is an observational longitudinal study to assess incidence of SARS-CoV-2 infection in Brazil. The study sample is stratified in nine age groups according decades of life, equally distributed in both sexes, with an expected incidence of 10%, at least, during the study period of 24 months. For the first age groups, (0-9, 10-19 and 20-29 years), sample was calculated with the minimum expected incidence of COVID-19 among infected, regardless severity, is 10%. For the latest age groups (30-39, 40-49, 50-59, 60-69, 70-79 and 80+), the sample was calculated with the expected minimum incidence of hospitalization due to COVID-19 according to estimates per age group reported by Verity R et al. https://doi.org/10.1016/S1473-3099(20)30243-7 After the consent procedure, all participants will have a short interview, a IgG/IgM SARS-CoV-2 rapid test and a blood withdrawal to obtain serum for neutralizing antibodies. These procedures will be repeated every four weeks until the end of the study. Individuals with symptoms compatible will be followed-up to confirm COVID-19 diagnosis as well as to assess severity, need for hospitalization and assisted ventilation, sequels, and eventual reinfection. Levels of neutralizing antibodies and other immune markers will be prospectively assessed in all infected participants, either asymptomatic and symptomatic.

Official Title
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Assessment of Incidence of SARS-CoV-2 Infection and COVID-19 in Brazil

Conditions
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COVID-19

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Any sex or age Providing informed consent Agreement with all study visits, procedure and contacts Exclusion Criteria: Previous suspected or confirmed COVID-19 Febrile illness in the latest 72 hours Olfactory or gustatory dysfunction in the last three months Healthcare worker in a service with routine attention to COVID-19 patients Any conditions that can might hurdle participant's compliance to the study in tha opinion of the study team
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

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 0-9 years<br>Participants aging 0-9 years | |
| 10-19 years<br>Participants aging 10-19 years | |
| 20-29 years<br>Participants aging 20-29 years | |
| 30-39 years<br>Participants aging 30-39 years | |
| 40-49 years<br>Participants aging 40-49 years | |
| 50-59 years<br>Participants aging 50-59 years | |
| 60-69 years<br>Participants aging 60-69 years | |
| 70-79 tears<br>Participants aging 70-79 years | |
| 80+ years<br>Participants aging 80 years or more | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of SARS-CoV-2 infection | Number of cases with serological/virological diagnosis for SARS-Co-2 infection | 24 months | 
| Incidence of COVID-19 | Number of cases of symptomatic SARS-CoV-2 infection | 24 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of hospitalization due to COVID-19 | Number of cases of hospitalization due to symptomatic SARS-Co-2 infection | 24 years | 
| Level of neutralizing antibodies | Level of neutralizing antibodies in participants with SARS-Co-2 infection | 24 months | 
| Previous SARS-CoV-2 infection | Positive serology for SARS-Co-2 infection at baseline | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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COVID-19, SARS-CoV-2 infection, Asymptomatic Infections, Antibodies, Neutralizing, Immunity, Humoral