Abstract
Global surveillance programs for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are showing the emergence of variants with mutations in the spike protein. Genomic and laboratory surveillance are important to determine if these variants may be more infectious or less susceptible to antiviral treatments and vaccine-induced antibodies. Three of the most predominant SARS-CoV-2 variants in Colombia during the epidemiological peaks of 2021 were isolated: Mu, a variant of interest; Gamma, a variant of concern; B.1.111, which lacks genetic markers associated with greater virulence. Microneutralization assays were performed by incubating 120 mean tissue culture infectious doses (TCID50) of each SARS-CoV-2 isolate with five two-fold serial dilutions of sera from 31 BNT162b2-vaccinated volunteers. The mean neutralization titer (MN50) was calculated by the Reed–Muench method. At the end of August, Mu represented 49% of coronavirus disease 2019 (COVID-19) cases in Colombia, followed by 25% of Gamma. In contrast, B.1.111 became almost undetectable. The evaluation of neutralizing antibodies suggests that patients vaccinated with BNT162b2 generate neutralizing antibody titers against the Mu variant at significantly lower concentrations relative to B.1.111 and Gamma. This study shows the importance of continuing surveillance programs of emerging variants, as well as the need to evaluate the neutralizing antibody response induced by other vaccines.
Highlights
Between October and December 2020, genomic epidemiology data from the emerging SARS-CoV-2 lineages B.1.1.7 (Alpha), B.1.351 (Beta), and P.1 (Gamma) suggested a significant association with increased transmissibility, and, a global risk to public health [1]
Three SARS-CoV-2 variants were isolated, Mu (B.1.621 lineage, GISAID ID EPI_ISL_ 1821065), Gamma (P.1 lineage, GISAID ID EPI_ISL_2500971), which was classified as a variant of concern (VOC) by the World Health Organization (WHO), and B.1.111 (GISAID ID EPI_ISL_526971), which lacks genetic markers associated with greater virulence
Data from the routine genomic surveillance of SARS-CoV-2 in Colombia show the epidemiologic dynamics of SARS-CoV-2 lineages in the country during the second and third epidemiological peaks between January and August 2021 [6,8]
Summary
Between October and December 2020, genomic epidemiology data from the emerging SARS-CoV-2 lineages B.1.1.7 (Alpha), B.1.351 (Beta), and P.1 (Gamma) suggested a significant association with increased transmissibility, and, a global risk to public health [1]. With this evidence, the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) established a hierarchical classification system to distinguish the emerging variants of SARS-CoV-2 into a variant of interest (VOI) or variant of concern (VOC) [2]. The P.1 (Gamma) lineage was identified in November 2020 in Brazil and designated as a VOC in January 2021 [5] This lineage spread worldwide and diverged into 22 sub-lineages, with a higher prevalence in American countries, including Haiti, Brazil, Venezuela, and Trinidad and Tobago [9]. In Colombia, this lineage had a prevalence of around 40% during the first and second epidemic peaks [11], where it diverged into a few sub-lineages, including one carrying mutations on the spike (S) protein, with evidence of escape from neutralizing antibodies [4,6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
