Abigail BanerjeeFebruary 26, 2022 10:43:26 AM
As “Mrs. Rona”, known as Coronavirus, celebrates her first birthday since entering our lives, the demand for terms such as pandemic, personal protective equipment, antibodies, antigens, etc. has increased and is now part of our daily vocabulary group. Many of us may now understand the complex process of a vaccine in development, the clinical trials it is going through, and the regulatory approvals it might need before it’s offered. We lived and learned.
As SARS-CoV-2 has rapidly “mutated”, new “variants” of the virus have emerged in many parts of the world. In the pre-COVID-19 era, we might have used this new slice of information to wow friends or family over dinner or cocktails. But let’s be honest, the variables in question are unlikely to allow this to happen anytime soon.
Next let’s dive in and understand the basics …
What is a virus?
Before the COVID-19 pandemic, we had mysteriously heard about disease-causing viruses like Ebola in Guinea and the Congo, swine flu or bird flu in India and Russia, AIDS, etc., and we now know that SARS-CoV-2 causes COVID-19 disease.
According to a report from Scientific AmericanFor many years, the scientific community has debated about the definition of a virus; First as a poison, then a life form and then a biochemical.
Today, viruses are somewhere between a living and an inanimate organism.
a virus It consists of a nucleus of genetic material (DNA or RNA) surrounded by a protective layer of protein. They can attach to host cells and use the host cell’s machinery to multiply its genetic material. Once this replication process is complete, the virus leaves the host either by budding or exiting the cell, destroying it in the process.
Viruses cannot reproduce on their own, but once they bind to the host cell, they can thrive and affect the behavior of the host cell in a way that harms the host and benefits the virus.
What is the strain?
The strain, according to a report by V. Conversation, Is a differentially constructed variant that exhibits distinct physical characteristics and behaves differently from the original virus. These behavioral differences can be subtle or apparent.
Coronaviruses, such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), are studded with protein “mutations” that bind to receptors on their victims’ cells. SARS-CoV-2 is now one of only a few other known strains in the coronavirus family, including SARS and MERS viruses.
Experts believe that the term breed is often misused.
“There is one strain of the Coronavirus. It is SARS-CoV-2. This is the only strain, and there are different types of this strain.” The Independent It quoted Professor Tom Connor of Cardiff University’s School of Biological Sciences as saying.
What is a mutation?
A virus consists of a sequence of either DNA or RNA, which are basically a series of nucleotide letters that code for genes in all living things. Any change in these letters is called a mutation, and it occurs when the virus sequence repeats itself. Mutations happen very randomly in the virus – a fact that could work for us or against us in a pandemic scenario. The mutation can be beneficial to the virus and make it stronger, or it can be harmful and reduce its virulence.
SARS-COV-2, unlike the influenza virus, contains a protein known as a proofreading enzyme. The enzyme is similar to what a newspaper copy editor does, checks for spelling errors on a page. This enzyme will make corrections, based on the original virus sequence. Therefore, if there are any changes that occurred due to a random mutation, he would try to correct them.
Just like a human copy editor, sometimes a mutation slips through the correction enzyme and remains. As the mutant virus particle multiplies, its entire genome including the mutation site is replicated and carried forward by future generations of the virus.
So, how does one know if a virus has mutated? This is where the virologist comes in. Virologists work tirelessly to sequence all the variables that infect people. The original virus, found in Wuhan, is used for comparison with the altered coronavirus variants.
What is the alternative?
Simply put, “a variant is a version of the virus that has accumulated enough mutations to represent a separate branch in the family tree,” Says Infectious disease expert Dr. Amish Adalja is a senior research fellow at the Johns Hopkins Center for Health Security.
Every mutation and strain of a virus is a variant, but every variant is not a strain.
Most of the variants are not a cause for concern. This is because the mutations have not caused any drastic change to the virus in question. However, when a group of mutations do occur, they can sometimes affect the way the virus behaves, spreads, or infects people. This is when the variable becomes a “variable of concern”. The classic example is the new variants that are spreading across parts of the United Kingdom, Africa and Brazil.
Scientists are closely monitoring SARS-CoV-2 variants in order to understand how genetic changes to the virus can affect infection (and thus its spread), disease severity, treatment, and effectiveness of available vaccines. Says Dr. Thomas Russo, Professor and Chair of the Department of Infectious Diseases at the University of Buffalo, New York.
What are the new variables in circulation?
A type of SARS-CoV-2 known as B.1.1.7 has been spreading across the UK since December 2020, and cases are now popping up all over the world. Scientists have found some evidence that this variant has an increased risk of death compared to the other variants.
In South Africa, another SARS-CoV-2 known as B.1.351 has appeared. It has some similarities to the UK variant and can also re-infect people who have recovered from other COVID-10 variants. There is also some evidence that AstraZeneca and Moderna vaccines are not effective against this variant.
A variant known as P.1 appeared in Brazil, and was first discovered in humans travel From the South American country to Japan. There is some evidence that this variant could affect the way the antibodies interact with the virus. The mutation in the P.1 variant stops the antibodies from recognizing and neutralizing the virus.
according to CDC, All three variants share a specific mutation called D614G that allows it to spread more quickly.
With new variants constantly emerging, it is important to be on top of the genome sequencing game. By doing this, we will be able to create new variants of public health interest (because they may be more contagious, cause more serious disease, and develop a vaccine or immune resistance) and we can advance them. However, ignoring these new emerging mutations will not make them go away and they could be harmful to us in the long run.
With input from S Krishnaswamy, Retired Professor of Bioinformatics from the School of Biotechnology, Madurai Camarrage University