Waves and variants of SARS-CoV-2: understanding the causes and effect of the COVID-19 catastrophe

Abstract

Graphical abstract The coronavirus disease-19 has left a permanent mark on the history of the human race. Severe acute respiratory syndrome coronavirus-2 is a positive-sense single-stranded RNA virus, first reported in Wuhan, China, in December 2019 and from there took over the world. Being highly susceptible to mutations, the virus's numerous variants started to appear, and some were more lethal and infectious than the parent. The effectiveness of the vaccine is also affected severely against the new variant. In this study, the infectious mechanism of the coronavirus is explained with a focus on different variants and their respective mutations, which play a critical role in the increased transmissibility, infectivity, and immune escape of the virus. As India has already faced the second wave of the pandemic, the future outlook on the likeliness of a third wave with respect to the Indian variants such as kappa, delta, and Delta Plus is also discussed. This review article aims to reflect the catastrophe of the variants of SARS-CoV-2 and the possibility of developing even more severe variants in the near future.

Emergence of SARS-CoV-2 Omicron (B.1.1.529) variant, salient features, high global health concerns and strategies to counter it amid ongoing COVID-19 pandemic

“…In May et al, 2021 , WHO proposed nomenclature as variants of concern (VOC) and variants of interest (VOI) for classification of SARS-CoV-2 emerging variants for easy-to-pronounce and non-stigmatizing labels along with the scientific nomenclature that is used by researchers and academicians ( WHO 2021b ). The continuous emergence of several variants and mutants of SARS-CoV-2 from time to time has led to increased morbidity and mortality amidst different waves of pandemic within the ongoing pandemic resulting into high global health concerns and panics ( Boehm et al, 2021 ; Thakur et al, 2021 ). After Alpha, Beta, Gamma and Delta SARS-CoV-2 variants, Omicron (B.1.1.529) variant has emerged recently during November 2021 as a highly mutated virus variant, classified as VOC by WHO on 26 November 2021, that is now attaining position of a dominant strain in several countries owing to its very high transmissibility ( NewsNodes, 2022 ; WHO, 2021a ; WHO, 2021c ).…”

Adherence to COVID-19 preventive practice and associated factors among pregnant women in Gondar city, northwest Ethiopia, 2021: Community-based cross-sectional study

“…), with high mutation characteristics and ineffectiveness of the vaccine makes the pandemic difficult to control in the world. This virus variation possibly creates more worst complications in the third wave of the pandemic [ 12 ].…”

Neurological toll of COVID-19

“…A critical point of focus concerning the management of the COVID-19 pandemic has been the surveillance of the new SARS-CoV-2 variants, of which some have been variants of concern (VOC) [4]. The emergence of alpha, beta, delta, and, very recently, omicron variants of concern (VOCs) have and are linked with surge in infections leading to different waves of infections around countries or sometimes globally also [5,6]. The emergence of new variants is already stirring feelings of anger, uncertainty, and frustration in people amidst the pandemic which is adversely affecting mental health and their social and economic well-being which acts a breeding ground for various neuropsychiatric illnesses.…”