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

> **NCT04355338** · — · COMPLETED · sponsor: **Butantan Institute** · enrollment: 3520 (actual)

## Conditions studied

- COVID-19

## Interventions

_None listed._

## Key facts

- **NCT ID:** NCT04355338
- **Lead sponsor:** Butantan Institute
- **Sponsor class:** OTHER_GOV
- **Phase:** —
- **Study type:** OBSERVATIONAL
- **Status:** COMPLETED
- **Start date:** 2020-10-25
- **Primary completion:** 2021-10-30
- **Final completion:** 2024-10-30
- **Target enrollment:** 3520 (ACTUAL)
- **Last updated:** 2025-02-06


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT04355338

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT04355338, "Assessment of Incidence of SARS-CoV-2 Infection and COVID-19 in Brazil (AVISA)". Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/clinical/NCT04355338. Licensed CC0.

---

*[Clinical trials dataset](/datasets/clinical-trials) · CC0 1.0*