Omicron Sublineages Current Status in Ecuador (preprint)

The Omicron variant of SARS-CoV-2 is the latest pandemic lineage causing COVID-19. Despite having a vaccination rate ≥ 85% Ecuador recorded a high incidence of Omicron from December 2021 to March 2022. Since Omicron emerged it is evolving into multiple sublineages with distinct prevalence in different regions. In this work, we use all Omicron sequences from Ecuador available at GISAID until March 2022 and the software Nextclade and Pangolin to identify which lineages circulate in this country. We detected 12 different sublineages (BA.1, BA.1.1, BA.1.1.1, BA.1.1.14, BA.1.1.2, BA.1.14, BA.1.15, BA.1.16, BA.1.17, BA.1.6, BA.2, BA.2.3), which has been reported in Africa, America, Europe, and Asia suggesting multiple introduction events. Sublineages BA.1.1 and BA.1 were the most prevalent. Genomic surveillance must continue to evaluate the dynamic of current sublineages, early introduction of new ones and vaccine efficacy against evolving SARS-CoV-2.

Genomic epidemiology of SARS-CoV-2 transmission lineages in Ecuador (preprint)

Characterisation of SARS-CoV-2 genetic diversity through space and time can reveal trends in virus importation and domestic circulation, and permit the exploration of questions regarding the early transmission dynamics. Here we present a detailed description of SARS-CoV-2 genomic epidemiology in Ecuador, one of the hardest hit countries during the early stages of the COVID-19 pandemic. We generate and analyse 160 whole genome sequences sampled from all provinces of Ecuador in 2020. Molecular clock and phylgeographic analysis of these sequences in the context of global SARS-CoV-2 diversity enable us to identify and characterise individual transmission lineages within Ecuador, explore their spatiotemporal distributions, and consider their introduction and domestic circulation. Our results reveal a pattern of multiple international importations across the country, with apparent differences between key provinces. Transmission lineages were mostly introduced before the implementation of non-pharmaceutical interventions (NPIs), with differential degrees of persistence and national dissemination.

Detection of the new SARS-CoV-2 variant B.1.526 with the Spike E484K mutation in South America (preprint)

Here, we report two sequences of the new SARS-CoV-2 variant recently detected and designed as B.1.526. This variant carries the immune escape-associated mutation E484K and additional mutations in the S, N, NSP2, NSP3, NSP4, NSP6, NSP8, NSP12 and NSP13 genes. Viral sequences were obtained from an individual traveling from the US to Equator with a negative RT-PCR and from one of his closest contacts that became infected. These cases should be considered an alert for the potential circulation of a new variant of concern with the E484K mutation in South America

A suspected case of SARS-CoV-2 persistence with reactivation (preprint)

Reinfections with SARS-CoV-2 have been verified by the presence of phylogenetically distant viruses in each episode. Here, we report a suspected case of SARS-CoV-2 persistence with reactivation in a 35-years old patient presenting positive RT-PCR on April 7th and August 7th, each episode characterized by mild and severe symptoms, respectively. Sequencing of viral genomes identified only two SNPs indicating the presence of genetically linked viruses for the first time. Subsequently to hospital discharge, the patient presented a positive diagnosis for SARS-CoV-2 in stool, urine and semen samples.