SARS-CoV-2 introduction and lineage dynamics across three epidemic peaks in Southern Brazil: massive spread of P.1

BackgroundGenomic surveillance of SARS-CoV-2 is paramount for understanding viral dynamics, contributing to disease control. This study analyzed SARS-CoV-2 genomic diversity in Rio Grande do Sul (RS), Brazil, including the first case of each Regional Health Coordination and cases from three epidemic peaks. MethodsNinety SARS-CoV-2 genomes from RS were sequenced and analyzed against SARS-CoV-2 datasets available in GISAID for phylogenetic inference and mutation analysis. ResultsSARS-CoV-2 lineages among the first cases in RS were B.1 (33.3%), B.1.1.28 (26.7%), B.1.1 (13.3%), B.1.1.33 (10.0%), and A (6.7%), evidencing SARS-CoV-2 introduction by both international origin and community-driven transmission. We found predominance of B.1.1.33 (50.0%) and B.1.1.28 (35.0%) during the first epidemic peak (July-August, 2020), emergence of P.2 (55.6%) in the second peak (November-December, 2020), and massive spread of P.1 and related sequences (78.4%), such as P.1-like-II, P.1.1 and P.1.2 in the third peak (February-April, 2021). Eighteen novel mutation combinations were found among P.1 genomes, and 22 different spike mutations and/or deletions among P.1 and related sequences. ConclusionsThis study shows the dispersion of SARS-CoV-2 lineages in Southern Brazil, and describes SARS-CoV-2 diversity during three epidemic peaks, highlighting the spread of P.1 and the high genetic diversity of currently circulating lineages. Genomic monitoring of SARS-CoV-2 is essential to guide health authorities decisions to control COVID-19 in Brazil. SummaryNinety SARS-CoV-2 genomes from Rio Grande do Sul, Brazil, were sequenced, including the first cases from 15 State Health Coordination regions and samples from three epidemic peaks. Phylogenomic inferences showed SARS-CoV-2 lineages spread, revealing its genomic diversity.

Emergence of the novel SARS-CoV-2 lineage P.4.1 and massive spread of P.2 in South Brazil

South Brazil has been the novel epicenter of Coronavirus Disease 2019 (COVID-19) in 2021, accounting for the greatest number of cumulative cases and deaths (per 100 thousand inhabitants in a week) worldwide. In this study, we analyzed 340 whole genomes of SARS-CoV-2, which were sampled between April and November 2020 in 33 cities in South Brazil. We demonstrated the circulation of two novel emergent lineages, described here as P.4 and P.4.1 (provisionally termed VUI-NP13L), and seven lineages that had already been assigned (B.1.1.33, B.1.1.28, P.2, B.1.91, B.1.1.94, B.1.195 and B.1.212). P.2 and P.4.1 demonstrated massive spread from approximately September/October 2020. Constant and consistent genomic surveillance is crucial to identify newly emerging SARS-CoV-2 lineages in Brazil and to guide decision making in the Brazilian Public Healthcare System.