Mutation hotspots, geographical and temporal distribution of SARS-CoV-2 lineages in Brazil, February 2020-2021: insights and limitations from uneven sequencing efforts

The COVID-19 pandemic has already reached approximately 110 million people and it is associated with 2.5 million deaths worldwide. Brazil is the third worst-hit country, with approximately 10.2 million cases and 250 thousand deaths. International efforts have been established to share information about SARS-CoV-2 epidemiology and evolution. However, sequencing facilities and research investments are very heterogeneous across different regions and countries. The understanding of the SARS-CoV-2 evolution plays a significant role in the development of effective strategies for public health and disease management. We aimed to analyze the available and high-quality genome sequences from Brazil between February 2020 and February 2021 to identify mutation hotspots, geographical and temporal distribution of SARS-CoV-2 lineages by using phylogenetics and phylodynamics analyses. We describe heterogeneous and episodic sequencing efforts, the progression of the different lineages along time, evaluating mutational spectra and frequency oscillations derived from the prevalence of novel and specific lineages across different Brazilian regions. We found at least seven major (1-7) and two minor clades (4.2 and 5.3) related to the six most prevalent lineages in the country and described its spatial distribution and dynamics. The emergence and recent frequency shift of lineages (P.1 and P.2) containing mutations of concern in the spike protein ( e. g ., E484K, N501Y) draws attention due to their association with immune evasion and enhanced receptor binding affinity. Improvements in genomic surveillance are of paramount importance and should be extended in Brazil to better inform policy makers and enable evidence-based decisions to fight the COVID-19 pandemic.