Surveillance of SARS-CoV-2 variants in Argentina: detection of Alpha, Gamma, Lambda, Epsilon and Zeta in locally transmitted and imported cases
Authors: Carolina Torres , Laura Mojsiejczuk , Dolores Acuña , Sofía Alexay , Ariel Amadio , Paula Aulicino , Humberto Debat , Franco Fernández , Stephanie Goya , Guido König , Mercedes Nabaes Jodar , Luis Pianciola , Sofía Bengoa , Marco Cacciahue , Cecilia Camussone , José Dus Santos María , Florencia Eberhardt María , Ailen Fernandez , Inés Gismondi María , Matías Irazoqui , Silvina Lusso , Nathalie Marquez , Marianne Muñoz , Mónica Natale , Belén Pisano , Andrea Puebla , Viviana Re , Ezequiel Sosa , Jonathan Zaiat , Sebastián Zunino , Darío Do porto , Elina Acevedo María , Cristina Alvarez Lopez , Laura Álvarez María , Patricia Angeleri , Andrés Angelletti , Manuel Arca , Gabriela Barbas , Ana Bertone , Agustina Bonnet , Ignacio Bourlot , Alejandro Castello , Gonzalo Castro , Carolina Ceriani , Carlos Cimino , Julián Cipelli , María Colmeiro , Andrés Cordero , Carolina Cristina , Sofia Di Bella , Regina Ercole , Yesica Espasandin , Carlos Espul , Andrea Falaschi , Facundo Fernandez Moll , Andrea Gatelli , Sandra Goñi , Estela Jofré María , José Jaramillo , Natalia Labarta , Agustina Lacaze María , Rocio Larreche , Viviana Leiva , Gustavo Levin , Erica Luczak , Marcelo Mandile , Carla Massone , Melina Mazzeo , Carla Medina , Belén Monaco , Luciana Montoto , Viviana Mugna , Alejandra Musto , Guillermo Ojeda , Carolina Pintos , Marcia Pozzati , Marilina Rahhal , Claudia Rechimont , Federico Remes Lenicov , Gabriela Rompato , Vanesa Seery , Leticia Siri , Julieta Spina , Cintia Streitenberger , Ariel Suárez , Jorgelina Suárez , Paula Sujanski , Manuel Talia Juan , Clara Theaux , Guillermo Thomas , Marina Ticeira , Estefanía Tittarelli , Rosana Toro , Osvaldo Uez , Belén Zaffanella María , Cecilia Ziehm , Martin Zubieta , Alicia Mistchenko , Laura Valinotto , Mariana Viegas 
Published: July 2021

Molecular surveillance of SARS-CoV-2 variants was performed on a total of 2,406 samples from the capital city and nine provinces of Argentina, during 30 epidemiological weeks (EW) that covered the end of the first wave and the beginning of the ongoing second wave of the COVID-19 pandemic in the country (EW 44/2020 to EW 20/2021). The surveillance strategy was mainly based on Sanger sequencing of a Spike coding region that allows the simultaneous identification of signature mutations associated with worldwide circulating variants. In addition, whole SARS-CoV-2 genome sequences were obtained from 456 samples. The main variants found were Gamma, Lambda and Alpha, and to a lesser extent, Zeta and Epsilon. Whereas Gamma dominated in different regions of the country, both Gamma and Lambda prevailed in the most populated area, the metropolitan region of Buenos Aires (MABA), although showing a heterogeneous distribution along this region. This cost-effective surveillance protocol allowed for a rapid response in a limited access to resources scenario, added information on the expansion of the Lambda variant in South America and contributed to the implementation of public health measures to control the disease spread in Argentina.