Adolfo Lutz I. Instituto Adolfo Lutz points out that variant P.4 circulated in SP as P.1 before the new genetic classification – June 15, 2021. Bepa [Internet]. 2021 Jun. 30 [cited 2025 Apr. 3];18(210):65-7. Available from: https://periodicos.saude.sp.gov.br/BEPA182/article/view/36715