COVID-Inconfidentes - SARS-CoV-2 seroprevalence in two Brazilian urban areas during the pandemic first wave: study protocol and initial results. SciELO Preprints, 2021. DOI: 10.1590/SciELOPreprints.2720. Disponível em: https://preprints.scielo.org/index.php/scielo/preprint/view/2720. Acesso em: 16 jan. 2026.