Borges, VítorSousa, CarlosMenezes, LuísGonçalves, António MaiaPicão, MiguelAlmeida, José PedroVieita, MargaridaSantos, RafaelSilva, Ana RitaCosta, MarianaCarneiro, LuísCasaca, PedroPinto-Leite, PedroPeralta-Santos, AndréIsidro, JoanaDuarte, SílviaVieira, LuísGuiomar, RaquelSilva, SusanaNunes, BaltazarGomes, João P.2022-07-042022-07-042021-03Euro Surveill. 2021 Mar;26(10):2100131. doi: 10.2807/1560-7917.ES.2021.26.10.21001301560-7917http://hdl.handle.net/10400.18/8056We show that the SARS-CoV-2 B.1.1.7 lineage is highly disseminated in Portugal, with the odds of B.1.1.7 proportion increasing at an estimated 89% (95% confidence interval: 83-95%) per week until week 3 2021. RT-PCR spike gene target late detection (SGTL) can constitute a useful surrogate to track B.1.1.7 spread, besides the spike gene target failure (SGTF) proxy. SGTL/SGTF samples were associated with statistically significant higher viral loads, but not with substantial shift in age distribution compared to non-SGTF/SGTL cases.engB.1.1.7 LineageRT-PCRSARS-CoV-2Genome SequencingLaboratory SurveillanceSpike Gene Target Failure (SGTF)Spike Gene Target Late Detection (SGTL)Infecções RespiratóriasEstados de Saúde e de DoençaPortugaljournal article10.2807/1560-7917.ES.2021.26.10.2100130