Open AccessSARS-CoV-2 B.1.1.7 Decline Is Not Driven by the Introduction of a More Successful Variant
Author(s) -
Cristina RodríguezGrande,
Sergio BuenestadoSerrano,
Luís Alcalá,
Pedro J. SolaCampoy,
Andrea MoleroSalinas,
Álvaro Otero-Sobrino,
Jorge Rodríguez-Grande,
Víctor Manuel de la Cueva García,
Javier AdánJiménez,
Carla Rico-Luna,
Carmen Losada,
Pilar Catalán,
Patricia Muñóz,
Laura PérezLago,
Darío García de Viedma
Publication year - 2021
Publication title -
microbiology spectrum
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.502
H-Index - 51
ISSN - 2165-0497
DOI - 10.1128/spectrum.01128-21
Subject(s) - niche , delta , competition (biology) , covid-19 , lineage (genetic) , alpha (finance) , biology , demography , ecology , medicine , genetics , virology , gene , physics , surgery , disease , sociology , outbreak , infectious disease (medical specialty) , construct validity , astronomy , patient satisfaction
The SARS-CoV-2 variant of concern (VOC) Delta (B.617.2 lineage) displaced the predominant VOC Alpha (B.1.1.7 lineage) in the United Kingdom. In Madrid, recent start of the decline of predominant VOC Alpha suggested an equivalent phenomenon. However, 11 different variants, none overrepresented in frequency, occupied progressively over a period of 7 weeks the niche previously dominated by VOC Alpha. Only after these 7 weeks, VOC Delta started to emerge. Viral competition due to the entry of VOC Delta is not the major force driving the start of VOC Alpha decline in Madrid. IMPORTANCE Our data indicate that the dynamics of SARS-CoV-2 VOCs turnover in our setting differ from those proposed for other countries. A systematic genomic analysis, updated on a weekly basis, of representative randomly selected samples of SARS-CoV-2 circulating variants allowed us to define a lapse of 7 weeks between the start of VOC Alpha decline and the final emergence of VOC Delta. During this period, VOC Alpha showed a sustained decline, while 11 VOCs, variants of interest (VOIs), and other identified variants, none overrepresented, occupied the niche left by VOC Alpha. Only after these 7 weeks, emergence of VOC Delta occurred, indicating that viral competition involving VOC Delta was not the exclusive direct driving force behind the starting of VOC Alpha decline.