Emerging COVID-19 variants and their impact on SARS-CoV-2 diagnosis, therapeutics and vaccines

Abstract

The emergence of novel and evolving variants of SARS-CoV-2 has fostered the need for change in the form of newer and more adaptive diagnostic methods for the detection of SARS-CoV-2 infections. On the other hand, developing rapid and sensitive diagnostic technologies is now more challenging due to emerging variants and varying symptoms exhibited among the infected individuals. In addition to this, vaccines remain the major mainstay of prevention and protection against infection. Novel vaccines and drugs are constantly being developed to unleash an immune response for the robust targeting of SARS-CoV-2 and its associated variants. In this review, we provide an updated perspective on the current challenges posed by the emergence of novel SARS-CoV-2 mutants/variants and the evolution of diagnostic techniques to enable their detection. In addition, we also discuss the development, formulation, working mechanisms, advantages, and drawbacks of some of the most used vaccines/therapeutic drugs and their subsequent immunological impact. Key message The emergence of novel variants of the SARS-CoV-2 in the past couple of months, highlights one of the primary challenges in the diagnostics, treatment, as well as vaccine development against the virus. Advancements in SARS-CoV-2 detection include nucleic acid based, antigen and immuno- assay-based and antibody-based detection methodologies for efficient, robust, and quick testing; while advancements in COVID-19 preventive and therapeutic strategies include novel antiviral and immunomodulatory drugs and SARS-CoV-2 targeted vaccines. The varied COVID-19 vaccine platforms and the immune responses induced by each one of them as well as their ability to battle post-vaccination infections have all been discussed in this review.

A Rapid and Consistent Method to Identify Four SARS-CoV-2 Variants during the First Half of 2021 by RT-PCR

“…At the end of 2020, two other new variants with increased transmission and potential clinical importance emerged: the Beta variant identified in South Africa and the Gamma variant identified in Brazil [ 6 ]. The Alpha variant has several mutations located in the spike region, including the 69del, D614G, 70del 144del, E484K, S494P, N501Y, A570D, P681H, T716I, S982A, D1118H, and K1191N substitutions [ 7 ]. In Italy, on 18th March 2021, the prevalence of the Alpha England variant was 86.7%, with values ranging between 63.3% and 100% in individual regions, whereas the prevalence of the Gamma variant was 4.3% (0–36.2%), ranging between 0% and 36.2% in individual regions; at the time of the survey, the other monitored variants had a prevalence below 0.5% ( , accessed on 1 January 2022).…”

“…Beta variant, located in the spike region, has the following mutations: D80A, D215G, 241del, 242del, 243del, K417N, E484K, N501Y, D614G, and the A701V substitution. The Gamma variant shares N501Y, and D614G substitutions with Alpha and Beta variants; moreover, located in the spike region, it has the following mutations: E484K, L18F, T20N, P26S, D138Y, R190S, K417T, H655Y, and the T1027I mutation [ 7 ]. The new VOC, the Delta variant, was first detected in India in December 2020 [ 8 ].…”

“…As of October 2021, the variant had been detected in over 98 countries around the world and became the dominant variant in most of those countries, including the UK, Israel, and Italy. The Delta variant, located in the spike region, has the following mutations: T19R, V70F, T95I, G142D, E156-, F157-, R158G, A222V, W258L, K417N, L452R, T478K, D614G, P681R, and D950N [ 7 ]. Multiple mutations in the spike protein and other important genomic areas are common in these variants.…”

Alveolar macrophages: Achilles’ heel of SARS-CoV-2 infection

“…Vaccines and neutralizing antibodies have been shown to be effective in the control of viral spreading, which, unfortunately, are challenged by the high frequency of viral mutations. 136 – 139 The Current Omicron variant has evolved outrageous transmissibility, which harbors up to 36 mutations in the S protein but generates milder symptoms, increased frequent asymptomatic carriers and decreased hospitalization. 140 – 142 Despite the reduced virulence, people are continually afraid of the generation of the new mutated virus from Omicron, which has an increased virulence and can bring the next wave of catastrophe.…”

Anesthetic management of living-donor lung transplantation for end-stage COVID-19 lung failure

“…The coronavirus disease 2019 (COVID-19) pandemic remains ongoing [ 1 ]. Lung transplantation is a potentially life-saving treatment for end-stage post-COVID-19 lung failure [ 2 – 4 ].…”