Emerging Variants of Coronavirus- An Insight

Introduction:

Coronavirus, or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a virus that causes acute viral illness. Since the pandemic, many variants have emerged, including alpha, beta, gamma, delta, and omicron. As a result, the virus and its variants are emerging as a significant global health crisis.

What Is Meant by Emerging Variants of Coronavirus?

The emerging variants of coronavirus are the virus's mutations identified through genetic sequencing. These variants have changes in the protein spike of the virus, which affects the virus’s ability to bind and infect human cells. In addition, adaptive mutations in the viral genome alter the pathogenic potential of the virus. This mutation leads to viral evasion into the immune system and complicates vaccine development.

What Are the Variants of Concern of Coronavirus?

Several variants are identified, and a few variants of coronavirus are:

• Alpha (B.1.1.7): First variant found in the United Kingdom.

• Beta (B.1.351): First reported in South Africa.

• Gamma (P.1): First reported in Brazil.

• Delta (B.1.617.2): First reported in India.

• Omicron (B.1.1.529): First reported in South Africa.

• Epsilon (B.1.427/B.1.429): Reported in USA.

• Eta (B.1.525): Reported in Nigeria.

• Kappa (B.1.617.1): Reported in India.

• Iota (B.1.526): Reported in USA.

• Lambda (C.37): Reported in Peru.

How Are Variants Classified?

The variants of coronavirus are classified based on the prevalence and attributes of viruses:

• Variants Being Monitored (VBM): These variants include data that indicate a potential or clear impact on authorized medical aid or associated with the transmission but are no longer determined or are circulating at low levels.

• Variants Of Interest (VOI): These variants have specific genetic markers associated with receptor binding changes, affect the transmission, and reduce the efficacy of treatments, diagnostic impact, or disease severity.

• Variants Of Concern (VOC): These variants have evidence of transmissibility, disease severity, antibody neutralization due to previous infection or vaccination, ineffective to treatment, or failure to detect.

• Variant Of High Consequence (VOHC): These variants have clear evidence that preventive measures or medical aids have reduced effectiveness relative to previously circulating variants.

Why Are Emerging Variants of Coronavirus a Concern?

Emerging variants of the coronavirus (SARS-CoV-2) are a concern for several reasons:

• Increased Transmissibility: Some variants, such as the B.1.1.7 (alpha) first identified in the United Kingdom, are more easily transmitted from person to person. This leads to more infections and potentially a more rapid spread of the virus, putting additional strain on healthcare systems and increasing the number of severe cases and deaths.

• Reduced Vaccine Effectiveness: Some variants, such as the B.1.351 (beta) variant first identified in South Africa, have been shown to potentially reduce the effectiveness of certain vaccines. This could make it more challenging to achieve herd immunity and control the spread of the virus.

• Antiviral Resistance: The emergence of variants could also lead to developing resistance to antiviral medications, making it more difficult to treat infected individuals.

• Vaccine Hesitancy: The emergence of variants could also add to the public's vaccine hesitancy, which can slow down the vaccination campaign and prolong the pandemic.

• Economic Impact: The emergence of new variants could also lead to renewed lockdowns, disrupting the economy and further damaging businesses and livelihoods.

Overall, the emergence of new variants increases the uncertainty of the pandemic and challenges the current control measures. In addition, it highlights the importance of ongoing surveillance and genetic sequencing to detect new variants early and adjust public health measures and vaccine development accordingly.

What Is the Etiology of Emerging Variants?

• Coronaviruses are a large family of viruses that can cause illness, ranging from the common cold to severe diseases such as SARS, MERS (Middle East Respiratory Syndrome), and COVID-19. Like all viruses, coronavirus also mutates or changes their genetic material as they spread and replicate.

• The genetic material of coronaviruses is composed of RNA (ribonucleic acid), a type of nucleic acid. Unlike DNA (deoxyribonucleic acid), RNA is more prone to mutations, which can result from errors during replication. Some mutations are harmless and do not affect the virus’s ability to cause illness, while others may be beneficial or detrimental to the virus.

• The COVID-19 pandemic caused by SARS-CoV-2, the coronavirus that causes COVID-19, has led to several variants. Some of these variants have mutations in the spike protein of the virus, which is the protein that the virus uses to bind to and enter human cells. These mutations may change the shape of the spike protein, making it harder for the immune system to recognize and neutralize the virus and more transmissible.

• Variants of concern:

• Multiple variants of coronavirus are identified, and few of them are considered variants of concern that impact public health due to their transmissibility or virulence nature. However, the variants are associated with increased virulence, reduction in neutralization by antibodies obtained via natural infection or vaccination, the ability to evade detection, or a decrease in therapeutics or vaccination effectiveness.

What Is the Effect of Emerging Variants of Coronavirus?

The effects of coronavirus variants vary depending on the specific mutations present in the virus. Some variants are more transmissible- spread easily from person to person. Others may be resistant to treatment or vaccines, resulting in difficulty in controlling the spread of the virus.

The alpha (B.1.1.7) virus first identified in the UK has been more transmissible than earlier variants, leading to increased cases and hospitalizations. Other variants, such as B.1.351 and P.1, have also been found to be more transmissible than others.

Another variant, B.1.351, first identified in South Africa, has been found to have several mutations that may affect the virus’ ability to bind to human cells and evade the immune system. This variant is resistant to some of the treatments and vaccines available currently.

In addition, some variants also affect the severity of the illness caused by COVID-19. For example, there is some evidence that the B.1.1.7 variant is associated with a higher risk of hospitalization and death. However, more research is needed to understand these variants' effects on human health.

Genetic variation in the genes of SARS-CoV-2 has implications for pathogenesis, which mediates viral entry into human cells and is an essential target of vaccine sera monoclonal antibodies. The respiratory system is the primary target of coronavirus and affects the other major organs such as the gastrointestinal tract, cardiovascular, renal, hepatobiliary, and central nervous systems. Coronavirus-induced organ dysfunction occurs due to viral toxicity, ischemic injury caused by thrombosis, vasculitis, renin-angiotensin-aldosterone system, and immune dysregulation.

Conclusion:

The virus has the potential to mutate over time and tend to emerge variants. These variants can have mutations that make them more transmissible and virulent, with the ability to evade immunity generated by vaccines or previous infections. The ongoing surveillance and genetic efforts continue to monitor the spread of these variants, and research into their potential impact on the course of the pandemic is conducted. Therefore, people should continue to wear masks, social distancing, and get vaccinated to protect against the spread of the virus. In addition, scientists are working on new variants of vaccines and antiviral drugs to combat the emerging variants.