- A mutation is a change in the genetic sequence of a virus
- Mutated coronaviruses are more infectious but less dangerous: Experts
- In India there may be multiple strains of coronavirus floating: Experts
New Delhi: According to experts, the novel coronavirus, SARS-CoV-2 that is continuing to spread around the world may not be the same as the virus that emerged in Wuhan province of China in late 2019 and quickly became the cause of COVID-19 global pandemic in 2020. This is because, like many other viruses, coronavirus is also prone to changes in its genetic structure because of the process known as mutation. One of the most dominant variations of coronavirus common throughout Europe and recently discovered in Malaysia called D614G has sparked the discourse around the mutation of coronavirus. The newly documented case of reinfection in Hong Kong, China is also found to be infected with coronavirus that is different in genetic structure from the virus from his first infection that the patient had caught in March this year. NDTV spoke with experts to learn about how these mutated strains arise, are these going to be even more dangerous and will these affect the efforts being made across the world to develop a vaccine?
What Is A Mutation?
Explaining about mutation, Dr. Preeti Kumar, Vice President, Public Health System Support at the Public Health Foundation of India said,
Mutation is the property of a virus to undergo changes when it multiplies. As it replicates, it may not produce exact replicas of itself, resulting in the emergence of new strains, which may be more or at times less effective. Some strains die out, while the more effective ones, which spread efficiently, survive.
According to a study conducted by researchers in China and published in the journal National Science Review titled ‘On the Origin and Continuing Evolution of SARS-CoV-2’, earlier the novel coronavirus had emerged with amino acids of ‘S’ type which mutated into ‘L’ type. Amino Acids are organic compounds that combine to form proteins. In coronavirus, these proteins are found in the spikes of the receptor of the virus that helps in binding the virus with host cells. Receptors in the virus produce an immune response in the host body.
According to the study, the ‘L’ type strain of coronavirus became more dominant in China while the ‘S’ type coronavirus became more contagious in the rest of the world. However, in Europe, another strain of virus strain was found in February which swaps between amino acids D and G and was given the name – D614G. This strain became dominant in the whole of Europe along with many other parts of the world and was recently discovered in Malaysia.
According to Dr. KK Agarwal, President, Confederation of Medical Associations in Asia and Oceania (CMAAO) and Medtalks, Heart Care Foundation of India, a property of this strain is that it increases the number of spikes on the virus exponentially and thus make it more contagious because, with more spikes, it becomes easy for the virus to bind with more number of cells.
In India, the first strain of coronavirus was ‘L’ strain that originated in Wuhan, according to experts, which eventually mutated into ‘S’ and ‘G’ stains, which have spread across the country.
Can Mutation Make The Pandemic Even More Dangerous?
Dr. Kumar said that because of mutation of coronavirus, there may be multiple strains floating in the country, however, only one or two strains dominate. She further said that while the dominating mutated coronavirus strain may spread at an even faster pace, it may not be as effective or dangerous as the original virus. She further explains,
The lower case fatality ratio in the country, the very high levels of asymptomatic cases, does not indicate that these variants are more dangerous versions. We should remember that the virus needs a host to survive, multiply and spread further. All organisms need to develop an optimal relationship with their host to survive and propagate. If the pathogen (virus or bacteria) is lethal, it kills the host organism. (human or animal) and if the sufficient number of hosts die, the virus dies out too. Which the virus would not like to! So, it is in its own interest to not mutate into such a severe strain that it dies out. The current strain of COVID-19 continues to live and propagate and spread efficiently.
Dr. Agarwal said that a virus mutates in order to continue existing and to exist it would try to enter more and more bodies and would need its host to remain alive. He said,
Mutating viruses are more contagious but the virulence of such virus continues decreasing with each mutation. And so mutation is not something to be worried about because it results in a milder strain. The mortality caused by this virus is low but it is spreading fast among the younger population.
What Coronavirus Mutation Means For Vaccine Development Efforts?
According to Dr Paul Offit an American paediatrician specializing in infectious diseases, vaccines, immunology, and virology, as far as the impact of coronavirus mutation on vaccine development efforts goes, nothing conclusive can be said currently due to the lack of data. He said,
Coronavirus is genetically a single-stranded ribonucleic acid (RNA) virus. All viruses of this kind mutate. Influenza virus which is also a single-stranded RNA virus mutates so much that vaccination is required every year as the previous vaccine may not continue to provide protection. In the case of coronavirus, all we have right now are preliminary findings. There is no solid data as of now on if the mutation is making coronavirus more viral.
However, Dr. Agarwal said that the vaccine being developed will work even on the new strain of mutated coronavirus D614G. He said,
The gene D614G is on the outer surface of the virus and not on the receptor-binding domain (RBD) which is a fragment from the virus that gains entry into the host cells and generate an immune response. The spike protein present on the receptor which binds the receptor on the target cell of host body decides antibody formation. D614G strain does not affect that and so antibodies will be generated and there will not a need of a new set of antibodies or another kind of a vaccine. Therefore, when such a vaccine develops that proves to be successful on coronavirus, it will work on all kinds of mutations.
NDTV – Dettol Banega Swasth India campaign is an extension of the five-year-old Banega Swachh India initiative helmed by Campaign Ambassador Amitabh Bachchan. It aims to spread awareness about critical health issues facing the country. In wake of the current COVID-19 pandemic, the need for WASH (Water, Sanitation and Hygiene) is reaffirmed as handwashing is one of the ways to prevent Coronavirus infection and other diseases. The campaign highlights the importance of nutrition and healthcare for women and children to prevent maternal and child mortality, fight malnutrition, stunting, wasting, anaemia and disease prevention through vaccines. Importance of programmes like Public Distribution System (PDS), Mid-day Meal Scheme, POSHAN Abhiyan and the role of Aganwadis and ASHA workers are also covered. Only a Swachh or clean India where toilets are used and open defecation free (ODF) status achieved as part of the Swachh Bharat Abhiyan launched by Prime Minister Narendra Modi in 2014, can eradicate diseases like diahorrea and become a Swasth or healthy India. The campaign will continue to cover issues like air pollution, waste management, plastic ban, manual scavenging and sanitation workers and menstrual hygiene.