Emergence of SARS-CoV-2 Variants in the World: How Could This Happen?

Abstract

The COVID-19 pandemic has had a significant global impact, with more than 280,000,000 people infected and 5,400,000 deaths. The use of personal protective equipment and the anti-SARS-CoV-2 vaccination campaigns have reduced infection and death rates worldwide. However, a recent increase in infection rates has been observed associated with the appearance of SARS-CoV-2 variants, including the more recently described lineage B.1.617.2 (Delta variant) and lineage B.1.1.529/BA.1 (Omicron variant). These new variants put the effectiveness of international vaccination at risk, with the appearance of new outbreaks of COVID-19 throughout the world. This emergence of new variants has been due to multiple predisposing factors, including molecular characteristics of the virus, geographic and environmental conditions, and the impact of social determinants of health that favor the genetic diversification of SARS-CoV-2. We present a literature review on the most recent information available on the emergence of new variants of SARS-CoV-2 in the world. We analyzed the biological, geographical, and sociocultural factors that favor the development of these variants. Finally, we evaluate the surveillance strategies for the early detection of new variants and prevent their distribution outside these regions.

Associated-Onset Symptoms and Post-COVID-19 Symptoms in Hospitalized COVID-19 Survivors Infected with Wuhan, Alpha or Delta SARS-CoV-2 Variant

“…The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the agent causing the coronavirus disease, 2019 (COVID- 19), has change the world in the last two years. The quick spreading of SARS-CoV-2 virus across the world has been favored by the appearance of several variants such as Alpha, Beta, Gamma, Delta, Epsilon, Zeta, Eta, Theta, Lota, Kappa, Lambda and, more recently, Omicron [1]. Among all these variants, Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2) and Omicron (B.1.1.529/BA.1) have been considered the variants of concern (VOCs), in addition to the Wuhan variants [2].…”

Sputnik V Effectiveness against Hospitalization with COVID-19 during Omicron Dominance

“…This brings hope that a certain level of intense immunity, which is the result of the widespread use of various vaccines based on the original strain's Spike protein gene, will maintain its effectiveness against new variants of SARS-CoV-2. The emergence of such variants is expected [39]. An alternative to vaccination programs is the isolation and quarantine strategy [40], which is a considerably big-budget plan [41].…”

Comparative analysis of SARS-CoV-2 quasispecies in the upper and lower respiratory tract shows an ongoing evolution in the spike cleavage site

“…Yet, its rapid global spread has allowed to record thousands of mutations in public databases; some of those were favourable and have emerged worldwide ( Long et al, 2020 ). The emergence of VOCs was favored by more than 400 million of infections worldwide ( Parra-Lucares et al, 2022 ) with a more significant number of mutations observed in S sequences as compared to other genomic regions ( Yusof et al, 2021 ). Generally, mutations in viral structural such as S glycoprotein can play a crucial role in their virulence by possibly determining changes in their cellular tropism and the generation of antibody escape variants as reported for Delta and Omicron variants (Andrews et al, 2021; Dejnirattisai et al 2022 ; Mlcochova et al, 2021 ).…”