SARS-CoV-2: phenotype, genotype, and characterization of different variants

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19), a major international public health concern. Because of very similar amino acid sequences of the seven domain names, SARS-CoV-2 belongs to the Coronavirinae subfamily of the family Coronaviridae, order Nidovirales, and realm Riboviria, placed in exceptional clusters, but categorized as a SARS-like species. As the RNA virus family with the longest genome, the Coronaviridae genome consists of a single strand of positive RNA (25–32 kb in length). Four major structural proteins of this genome include the spike (S), membrane (M), envelope (E), and the nucleocapsid (N) protein, all of which are encoded within the 3′ end of the genome. By engaging with its receptor, angiotensin-converting enzyme 2 (ACE2), SARS-CoV-2 infects host cells. According to the most recent epidemiological data, as the illness spread globally, several genetic variations of SARS-CoV-2 appeared quickly, with the World Health Organization (WHO) naming 11 of them. Among these, seven SARS-CoV-2 subtypes have received the most attention. Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), and Omicron (B.1.617.2) are now designated as variations of concern (VOC) (B.1.1.529). Lambda (C.37) and Mu are variations of interest (VOI) (B.1.621). The remaining six are either being monitored or are no longer considered a threat. On the basis of studies done so far, antiviral drugs, antibiotics, glucocorticoids, recombinant intravenous immunoglobulin, plasma therapy, and IFN-α2b have been used to treat patients. Moreover, full vaccination is associated with lower infection and helps prevent transmission, but the risk of infection cannot be eliminated completely in vaccinated people.

Characteristics of the SARS-CoV-2 Omicron (B.1.1.529) Variant and Emerging Impact on Global Public Health

“…Recent Omicron variant case statistics consistently show faster spread in the UK, USA, and elsewhere, implying that faster growth scenarios are more plausible. 1 , 8 , 9 According to the CDC’s analytical methodologies, Omicron’s current quicker relative rate of growth compared to Delta predict that a major outbreak of illnesses might start in early January 2022 in the United States, with the maximum daily number of new infections surpassing previous peaks. 79 The rapid rate of growth in Omicron outbreaks is thought to be due to a combination of enhanced disease transmission and the ability to evade immunity, according to many laboratory trials and clinical investigations.…”

“…The COVID-19 symptoms due to the Omicron variant are milder ones as similar to previous variants. 9,22 However, the Omicron variant and other COVID-19 mutations could raise death rates. 40 People infected with the Omicron variation suffer symptoms comparable to the flu, such as cough, weariness, and head and body pains, whereas those infected with the Delta variant frequently report low oxygen levels, high pulse rates, and a loss of smell and taste.…”

“…[2][3][4][5][6][7] Subsequently, the discovery of the SARS-CoV-2 Omicron (B.1.1.529) variant in November 2021 sparked alarm globally because of its rapid rate of transmission and antibody escaping capability. [8][9][10] This heavily mutated variant is rapidly spreading around the world that is of great health concern. [11][12][13] The World Health Organization (WHO) designated this SARS-CoV-2 variant as the variant of concern (VOC) on November 26, 2021.…”

In silico screening of phenylethanoid glycosides, a class of pharmacologically active compounds as natural inhibitors of SARS-CoV-2 proteases

“…The SARS-CoV-2 genome is a single-stranded positive-sense RNA virus that encodes for many different proteins and enzymes. The genome is approximately 30,000 base pairs long and contains two open reading frames (ORFs) that produce all the proteins necessary for viral replication and virulence [5] .…”

SARS-CoV-2 infection in patients with melanoma: results of the Spanish Melanoma Group registry

“…The impact of the pandemic on patients with cancer also varies across different countries, depending on health resources and their management, so analyzing the results in Spain could help to understand the specific impact in this country. Additionally, virus evolution with the development of new variants has also modified the aggressiveness of the infection over time [ 24 ] while lock downs and primary prevention measures have been different during the period covered by the register, so the analysis of the infection morality in each wave is mandatory to understand how the impact of the infection has changed during pandemic.…”