Impact of SARS-CoV-2 Mu variant on vaccine effectiveness: A comparative genomics study at the peak of the third wave in Bogota, Colombia.

We assessed the circulation of severe acute respiratory syndrome coronavirus-2 variants amongst vaccinated military personnel in Bogotá, Colombia to evaluate the mutations of certain variants and their potential for breakthrough infection in vaccinated subjects. We observed that in vaccinated individuals the most frequent infecting lineage was Mu (B.1.621 and B.1.621.1). The above is possibly associated with specific mutations that confer it with vaccine-induced immune escape ability. Our findings highlight the importance of how genomic tracking coupled with epidemiological surveillance can assist in the study of novel emerging variants (e.g., Omicron) and their impact on vaccination efforts worldwide.

Epidemiological Dynamics of SARS-CoV-2 Variants During Social Protests in Cali, Colombia.

Background: The third wave of the global health crisis attributed to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus reached Colombia in March 2021. Over the following 6 months, it was interpolated by manifestations of popular disapproval to the actual political regime-with multiple protests sprouting throughout the country. Large social gatherings seeded novel coronavirus disease 2019 (COVID-19) variants in big cities and propagated their facile spread, leading to increased rates of hospitalizations and deaths. Methods: In this article, we evaluate the effective reproduction number (Rt) dynamics of SARS-CoV-2 in Cali, Colombia, between 4 April 2021 and 31 July 2021 based on the analysis of 228 genomes. Results: Our results showed clear contrast in Rt values between the period of frequent protests (Rt > 1), and the preceding and following months (Rt < 1). Genomic analyses revealed 16 circulating SARS-CoV-2 lineages during the initial period-including variants of concern (VOCs) (Alpha, Gamma, and Delta) and variants of interest (VOIs) (Lambda and Mu). Furthermore, we noticed the Mu variant dominating the COVID-19 distribution schema as the months progressed. We identified four principal clusters through phylogenomic analyses-each one of potentially independent introduction to the city. Two of these were associated with the Mu variant, one associated with the Gamma variant, and one with the Lambda variant. Conclusion: Our results chronicle the impact of large group assemblies on the epidemiology of COVID-19 during this intersection of political turmoil and sanitary crisis in Cali, Colombia. We emphasize upon the effects of limited biosecurity strategies (which had characterized this time period), on the spread of highly virulent strains throughout Cali and greater Colombia.

Epidemiological Indicators of SARS-CoV-2 (COVID-19) and Vaccination Effectiveness on the Report of Positive Cases in the Colombian Army.

The description of the epidemiological indicators of SARS-CoV-2 (COVID-19), such as the mortality rate (MR), the case fatality rate (CFR), and the attack rate (AR), as well as the geographical distribution and daily case reports, are used to evaluate the impact that this virus has had within the Colombian Army and its health system. As military forces around the world represent the force that defends sovereignty, independence, the integrity of the national territory, and the constitutional order, while maintaining migration controls in blocked border areas during this critical pandemic times, they must carry out strict epidemiological surveillance to control the situation among the servicemen. Up to date, the Colombian Army has faced a very high attack rate (AR = 8.55%) due, among others, to living conditions where active military personnel share bedrooms, bathrooms, and dining facilities, which facilitate the spread of the virus. However, being a mainly young and healthy population, the MR was 1.82 deaths/1,000 ha, while the CFR = 2.13% indexes consistently low if compared with those values reported for the national population. In addition, the effectiveness of vaccination is shown in daily cases of COVID-19, where, for the third peak, the active military population presented a decrease of positive patients compared to the dynamics of national transmission and the total population of the military forces (active, retired, and beneficiaries).

Phylogenomic Evidence of Reinfection and Persistence of SARS-CoV-2: First Report from Colombia.

The continuing evolution of SARS-CoV-2 and the emergence of novel variants have raised concerns about possible reinfection events and potential changes in the coronavirus disease 2019 (COVID-19) transmission dynamics. Utilizing Oxford Nanopore technologies, we sequenced paired samples of three patients with positive RT-PCR results in a 1-2-month window period, and subsequent phylogenetics and genetic polymorphism analysis of these genomes was performed. Herein, we report, for the first time, genomic evidence of one case of reinfection in Colombia, exhibiting different SARS-CoV-2 lineage classifications between samples (B.1 and B.1.1.269). Furthermore, we report two cases of possible viral persistence, highlighting the importance of deepening our understanding on the evolutionary intra-host traits of this virus throughout different timeframes of disease progression. These results emphasize the relevance of genomic surveillance as a tool for understanding SARS-CoV-2 infection dynamics, and how this may translate effectively to future control and mitigations efforts, such as the national vaccination program.