Effectiveness of Vaccination Against COVID-19 in Brazil: Case-Control Study

NCT05621928 | Active Not Recruiting

• 1 other identifier: 003/2021
• Study Type: observational
• Target: 3,920
• Locations: 1 country
• Sites: 1

Brief Summary

The main objective of the study is to evaluate the effectiveness of the vaccine against covid-19, recommended by the national immunization program. This is a multicentric, observational, case-control study. Participants Cases with the disease will be compared to Control Participants, that is, without the disease, regarding the vaccination history for Covid-19.Complementarily, an evaluation of cellular and humoral immunity will be carried out in a sample of both case and control participants, taking into account the vaccination history.

Conditions

COVID-19 Vaccines

Outcome Measures

Primary Outcomes (1)

• Evaluate the effectiveness of the vaccination against COVID-19.

  Confirmed disease (RT-PCR positive for SARS-CoV-2), according to:the clinical spectrum (of mild disease , moderate to severe) and outcome (disease-related death);according to the vaccine used, the number of doses and the interval rom the last dose to the onset of symptom;according to the presence of comorbidities and medication use; according to Region/State;according to vaccination coverage;according to circulating viral variants.

  12 months

Secondary Outcomes (2)

• Assess the humoral and cellular immune response

  15 months

• Analyze individual factors

  15 months

Study Arms (5)

cases with positive RT PCR result for Covid 19

Individuals aged 18 years or older, with a suspected clinical picture of COVID-19 virologically confirmed, that is, with positive RT-PCR for SARS-CoV-2 in a respiratory secretion sample collected in the first 7 days of the onset of symptoms , who did not have a positive RT-PCR result for SARS-CoV-2 in the 90 days preceding enrollment in the study.

Control

Individuals residing in the vicinity of the case, aged 18 years or older, without a suspected clinical picture of COVID-19 and with RT-PCR negative for SARS-CoV-2 in a respiratory secretion sample collected at the time of inclusion, followed by confirmation of the absence of signs and symptoms suggestive of COVID-19 within the next 7 days.

immunogenicity analyzes

a convenience sample composed of all cases exposed or not to vaccination and 200 controls, 100 vaccinated and 100 unvaccinated, for analysis of humoral response.

assessment of cellular immunity

a sample of 100 vaccinated cases and 100 unvaccinated cases followed prospectively, and 100 vaccinated controls 100 unvaccinated controls assessed spot-on at enrollment.

analysis of potential genetic risk factors for the occurrence of severe forms of COVID-19 (SRAG)

a total of 50 cases

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Participants virologically confirmed incident cases of COVID-19 and Control Participants without COVID-19 (no suspected symptomatology and RT-PCR negative for SARS-CoV in two consecutive naso/oropharyngeal swab samples).

You may qualify if:

• Agreement to participate in the study after reading, understanding and signing the informed consent.
• Availability and possibility of being followed up during the follow-up period defined in the study, through visits to research centers, home visits, telephone contacts or other means of digital communication.
• Completing the case or control definitions described below.

You may not qualify if:

• Behavioral, cognitive or psychiatric illness that, in the opinion of the responsible investigator or his/her medical representative, affects the participant's ability to understand and comply with the requirements of the study protocol;
• Any other condition that, in the opinion of the responsible investigator or his/her medical representative, may jeopardize the safety or rights of a potential participant or prevent him/her from complying with this protocol.

Sponsors & Collaborators

• The Immunobiological Technology Institute (Bio-Manguinhos) / Oswaldo Cruz Foundation (Fiocruz): lead

Study Sites (1)

Institute of Technology in Immunobiology Bio-Manguinhos/Fiocruz

Rio de Janeiro, 21040-900, Brazil

Location

Biospecimen

Retention: SAMPLES WITH DNA

oral and nasopharyngeal secretion, blood

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Target Duration: 12 Months
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: November 17, 2022
• First Posted: November 18, 2022
• Study Start: February 7, 2022
• Primary Completion: October 31, 2023
• Study Completion: December 30, 2024
• Last Updated: February 7, 2024

Record last verified: 2024-02

Locations

BR (1)